the speed of light
d parker
A boat is sailing east to west across the pacific. Say, Tokyo to L.A (The
distance is irrelevant, it could just be across a bay). The boat is
travelling at ten knots. At the mid-way point, the boat transmits a message
on the radio. We know that radio waves travel at the speed of light and for
the sake of the argument the frequency used transmits ground waves.( I know
the boat would really be using sky waves)
Is the signal going to L.A. travelling at the speed of light plus ten knots
and the signal going to Tokyo travelling at the speed of light less ten
knots?
Or does the Doppler effect come in to play. The signal travels at the speed
of light in both directions but is slightly stronger at L.A. and weaker at
Tokyo?
Good Sailing and Fair Weather
D Parker
Whitebear
In a word yes.
but :)
since light travels at 186,000 miles per sec
the plus or minus of 10 knots which is approx 10 miles/hour or 10/3600
=0.0027 miles per sec it is not going to Make any significant difference
:)
Whitebear
BTW if you want to doppler shift the red light at at traffic light to
green you need to be traveling at close to 1/2 the speed of light :)
Capt. Neal®
Respectfully,
Capt. Neal
~~~~~~~~~~~~~
d parker wrote in message
<3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au>...
Capt. Neal®
moves independently of the observer or the source.
Mike Barrs
The radio wave will travel in both directions at the same propagation
speed (speed of light), regardless of the boat's movement. The speed
of light is an absolute velocity -- it is not relative to anything. To
quote from a very good tutorial on the subject (see:
http://math.ucr.edu/home/baez/physics/speed_of_light.html):
"It is a basic postulate of the theory of relativity that the speed
of light is constant. This can be broken down into two parts:
* The speed of light is independent of the motion of the observer.
* The speed of light does not vary with time or place."
So... it doesn't matter what direction the boat is moving, and it
doesn't matter if the boat is moving 10 knots or 100,000 knots. In
your theoretical example (where we ignore the fact that it's not a
straight-line distance to the receiving antennas, and the wave isn't
travelling in a vacuum), the radio wave arrives at exactly the same
time at both antennas when the boat reaches the exact mid-point of the
voyage.
Here's the Doppler difference... and it only applies to wavelength,
not speed of propagaion of the radio wave. The boat's movement would
cause the wavelength to be stretched to an infinitesimally longer
frequency in the direction behind the boat, and crunched to an
infinitesimally shorter frequency in the direction ahead of the boat.
For the sake of this discussion, we could say that someone with a
perfect, ultra-sensitive radio receiver sitting in Toky or or L.A.
would notice that the boat's signal was drifting off the center
frequency. But that would be the only effect. The speed of
propagation for the wave is a "special", fixed constant.
None of this is intuitive or easy to understand, but the Universe just
works that way... as far as we can tell.
MikeB
(lurking here on a break from the astronomy forums)
d parker <davep...@optusnet.com.au> wrote in message
news:3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au...
Capt. Ahab
slightly by the difference in speed.
Captain Ahab
Gilligan
inertial frame (a rotating reference frame, the earth, - an accelerated
reference frame) and the velocities add. The has been demonstrated for
decades using satellites, ground radio waves and light.
Gilligan
In article <3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au>,
"d parker" <davep...@optusnet.com.au> wrote:
> Here's a hypothetical question.
>
> A boat is sailing east to west across the pacific. Say, Tokyo to L.A
(The
> distance is irrelevant, it could just be across a bay). The boat is
> travelling at ten knots. At the mid-way point, the boat transmits a
message
> on the radio. We know that radio waves travel at the speed of light
and for
> the sake of the argument the frequency used transmits ground waves.(
I know
> the boat would really be using sky waves)
>
> Is the signal going to L.A. travelling at the speed of light plus ten
knots
> and the signal going to Tokyo travelling at the speed of light less
ten
> knots?
>
> Or does the Doppler effect come in to play. The signal travels at the
speed
> of light in both directions but is slightly stronger at L.A. and
weaker at
> Tokyo?
>
> Good Sailing and Fair Weather
>
> D Parker
>
>
Sent via Deja.com http://www.deja.com/
Before you buy.
Gilligan
clocks are also synchronized using velocity addition. Light speed also
varies as a function of gravitational potential and the conditions of
the local field (be it gravity, electric, magnetic, etc). There is a
famous experiment conducted in the 1800's called the Fizeau experiment
which showed the speed of light changed when it travelled for or
against moving water in a pipe. Historically the measurement of the
speed of light over the years has shown it is slowing down. If this is
so it would explain the red shift observed in cosmology and severely
shake up the fundamental assumptions of cosmology.
Anyone who says the speed of light is constant and is unaffected by the
medium or fields through which it travels has a thin grasp on reality.
Gilligan
Gilligan
http://www.mathpages.com/rr/s2-07/2-07.htm
Explains the Sagnac effect from the reference frame of an inertial
observer. Aboard the accelerated reference frame (on the rotating disc,
as on the rotating earth) the observation is that the speed of light
does add/subtract with the external medium velocity because the
relative velocity between the emitter and receiver are zero. Hence the
radio waves travelling east go slower than the radio waves travelling
west.
Alan Baker
<wb...@home.com> wrote:
>Hi D :)
>
>In a word yes.
In a word: No!
The speed of light is a constant. Send if from a moving object with
respect to the receiver and it will still arrive at the same speed.
>
>but :)
>
>since light travels at 186,000 miles per sec
>
>the plus or minus of 10 knots which is approx 10 miles/hour or 10/3600
>=0.0027 miles per sec it is not going to Make any significant difference
Nope. The frequency will be shift a little, but the speed will be
exactly the same in both directions.
>:)
>
>Whitebear
>
>BTW if you want to doppler shift the red light at at traffic light to
>green you need to be traveling at close to 1/2 the speed of light :)
--
Alan Baker
Vancouver, British Columbia
"If you raise the ceiling four feet, move the fireplace from that wall to that
wall, you'll still only get the full stereophonic effect if you sit in the
bottom of that cupboard."
The_navigator
light which changes velocity but it is point of dectection which is
moving. hence the time of decteion changes because the distance
travelled by the light is different, not that the speed of light
changes.
Newbies, please note, that in a medium of constant refractive index the
speed of light does not vary!
Cheers MC (illuminating the problem for Gilligrovel)
In article <8ubtbh$oes$1...@nnrp1.deja.com>,
Gilligan
An observer that is moving with the source in the same accelerated
reference frame (example: here the rotating earth) observes a change in
velocity of light depending on whether the light moves against or with
the rotation. This is what happens on the surface of the rotating earth.
The point of detection is not moving relative to the source in the
above yet light velocity is dependent on direction. It is the rotation
of the earth that creates the velocity tensor (velocity a function of
direction), not the relative motion of the source and observer.
Your discussion only applies if the observer is in an inertial
reference frame - he does observe a path length change and movement of
the source. If the reference frame is the rotating frame of the
source, the path lengths stay the same (unless their is some "ether
contraction") and it is the velocity of light that changes. Light
velocity is not isotropic on the earth's surface.
Gilligan
In article <8uces1$952$1...@nnrp1.deja.com>,
Jonathan Ganz
the Atlantic, and the US. :-)
Come on now... this is basic stuff. :-)
In article <rBbO5.135743$bI6.5...@news1.giganews.com>,
Capt. Neal® <Capt...@BigBoot.com> wrote:
>Tokyo to L.A. is east to west??? Since when?
Jonathan
--
Jonathan Ganz
jg...@sailnow.com
http://www.sailnow.com
Per Elmsäter
data packet as does a european character. It is therefore completely clear
to anyone that isn't carrying his head under the arm, that the message going
to Tokyo will arrive at only half the speed of light. Supposing it's
daylight when the message is sent it will be night in Tokyo and they won't
even be able to see anything of the message until daybreak. That will slow
it down another 800 mph or so.
So don't ever send any messages to Tokyo whatever you do. You might even be
billed for translationg it back to readible English. That will slow it down
another 1233 mph so you might as well have put the message in a bottle and
swum over with it. Since you were traveling east to west you'd start
swimming east to make it back and end up in LA anyway.
--------------------------------------------------------
"Don't take yourself so seriously.
Life and the sea will take care of that, if given a chance."
Respectfully Perre
--------------------------------------------------------
"d parker" <davep...@optusnet.com.au> wrote in message
news:3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au...
Donal
The_navigator <the_na...@my-deja.com> wrote in message
news:8uces1$952$1...@nnrp1.deja.com...
> Well you certainly got that one confused Gilligrovel. It is not the
> light which changes velocity but it is point of dectection which is
> moving. hence the time of decteion changes because the distance
> travelled by the light is different, not that the speed of light
> changes.
>
> Newbies, please note, that in a medium of constant refractive index the
> speed of light does not vary!
So, I am on a travelator that is travelling at 96,000 miles per second. My
fellow scientist is in the corridor beside the travelator, and he is
stationary. Somebody on terra firma at the end of the travelator swithes on
a torch. Do we both detect the light passing us at the same speed?
If we do, then the light must be in two different places at the same time.
Is this correct?
Regards
Donal
--
d parker
DP
"Capt. Neal®" <Capt...@BigBoot.com> wrote in message
news:rBbO5.135743$bI6.5...@news1.giganews.com...
> Tokyo to L.A. is east to west??? Since when?
>
> Capt. Neal
> ~~~~~~~~~~~~~
>
>
> d parker wrote in message
> <3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au>...
d parker
DP
"Mike Barrs" <mba...@REMOVE-NOSPAM.nightviewer.com> wrote in message
news:jYcO5.4133$B14....@news4.mia...
The_navigator
If the observer is beside you then you both detect the light
flash at the same moment because the time taken for the light
flash to get there is L/c where L is the distance to the
flashlight. It does not matter that you are moving this just changes the
*apparent* wavelength of the beam (because your movement contracts your
measurement frame).
Gilligrovel
The phase change detected in the Sagnak effect is not due to the change
in the velocity of light, it is due to the motion changing the
*effective* length of the path (the observer is moving toawerds the
beam on one side and away on the other). Note that the interferometer
reports a *constant* phase difference whereas if the velocities were
different the fringes would be in constant motion. You can show that c
has not changed, because no matter what you do in you frame of reference
it is still c = delta x /delta t and as delta x contracts so does t !!!!
Can you see this?
Regards MC
undertand the picture heren article
<973729376.18906.2...@news.demon.co.uk>,
Gilligan
I understand what you are saying. However, if the entire apparatus is
contained on a rotating turntable and the source and receiver have no
relative motion, the speed of light is different if it is against or
with the rotation of the turntable. WRT the turntable, there is no path
length change due to rotation. WRT the aether or some "preferred"
reference frame the path length shortens.
On the surface of the rotating earth, in the reference frame of a fixed
point on the surface of the earth (rotating with it) the speed of light
is different from east to west than from west to east.
A photon is spewed from the sun and falls into the earth's
gravitational field. What happens?:
1. The photon accelerates due to gravity
2. The photon velocity remains the same but its frequency increases
3. The photon velocity slows down in the gravitational field (since
gravity "bends" light - it is a difractive process - changes its
velocity) but the additional energy of "falling" in the gravity field
increases the frequency of the photon.
Which one is it?
Gilligan
In article <8uctvf$mid$1...@nnrp1.deja.com>,
The_navigator
The_navigator
The correct answer is 2 but it is not because the velocity has gone
up -it has not. The key is that time is running slower in the
gravitation field and since the photon 'clock' is constant the observer
deeper in the gravity well sees a blue shift. Just remember c is a
constant, it is space and time that is not -OK?
Cheers MC
Dr Arm®
>
> Here's a hypothetical question.
>
> A boat is sailing east to west across the pacific. Say, Tokyo to L.A (The
> distance is irrelevant, it could just be across a bay). The boat is
> travelling at ten knots. At the mid-way point, the boat transmits a message
> on the radio. We know that radio waves travel at the speed of light and for
> the sake of the argument the frequency used transmits ground waves.( I know
> the boat would really be using sky waves)
Tokyo to LA is actually West to East. Let's use that.
>
> Is the signal going to L.A. travelling at the speed of light plus ten knots
> and the signal going to Tokyo travelling at the speed of light less ten
> knots?
No. The speed of light in a vacuum is the same for all observers. I
presume the vacuum as a part of your experiment.
>
> Or does the Doppler effect come in to play. The signal travels at the speed
> of light in both directions but is slightly stronger at L.A. and weaker at
> Tokyo?
Yes the Doppler comes into play, but not the way you seem to think it
works.
Since the boat is traveling W to E, it is adding energy to the wave
traveling in that direction.
Thus the light-radio wave traveling in that same direction has a greater
energy than the light-radio wave going the other way.
Greater energy means a blue shift for light, a shift toward higher
frequency for the radio wave.
Thus the wave traveling in the same direction as the boats velocity,
will arrive at the LA shore at the speed of light, but with a frequency
shift toward slightly higher frequency (shorter wavelength, same thing).
This is an example of the Dopples effect for electromagnetic waves.
But it will be way too smale to notice. If you really like I can
calculate it for you.
da
Dr Arm®
questions. If Einstien did not postulate it then Lorentz soon would
have.
Other people since have established that it seems to be in fact true.
da
Capt. NealŽ wrote:
>
> The speed of light is the speed of light. Einstein proved it
> moves independently of the observer or the source.
>
> Respectfully,
> Capt. Neal
> ~~~~~~~~~~~~~
>
> d parker wrote in message
> <3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au>...
> >Here's a hypothetical question.
> >
> >A boat is sailing east to west across the pacific. Say,
> Tokyo to L.A (The
> >distance is irrelevant, it could just be across a bay).
> The boat is
> >travelling at ten knots. At the mid-way point, the boat
> transmits a message
> >on the radio. We know that radio waves travel at the speed
> of light and for
> >the sake of the argument the frequency used transmits
> ground waves.( I know
> >the boat would really be using sky waves)
> >
> >Is the signal going to L.A. travelling at the speed of
> light plus ten knots
> >and the signal going to Tokyo travelling at the speed of
> light less ten
> >knots?
> >
> >Or does the Doppler effect come in to play. The signal
> travels at the speed
> >of light in both directions but is slightly stronger at
> L.A. and weaker at
> >Tokyo?
> >
Dr Arm®
none of this is correct. But it is very immaginative! :)
da
Dr Arm®
>
> The_navigator <the_na...@my-deja.com> wrote in message
> news:8uces1$952$1...@nnrp1.deja.com...
> > Well you certainly got that one confused Gilligrovel. It is not the
> > light which changes velocity but it is point of dectection which is
> > moving. hence the time of decteion changes because the distance
> > travelled by the light is different, not that the speed of light
> > changes.
> >
> > Newbies, please note, that in a medium of constant refractive index the
> > speed of light does not vary!
>
> So, I am on a travelator that is travelling at 96,000 miles per second. My
> fellow scientist is in the corridor beside the travelator, and he is
> stationary. Somebody on terra firma at the end of the travelator swithes on
> a torch. Do we both detect the light passing us at the same speed?
Yes. But not at the saem time.
>
> If we do, then the light must be in two different places at the same time.
> Is this correct?
No. It is in two different places at two unrelated times. And at two
different colors.
da
>
> Regards
>
> Donal
> --
Dr Arm®
da
Dr Arm®
da
d parker
"Dr ArmŽ" <Ar...@Armory.arm> wrote in message news:3A0A21...@Armory.arm...
snip
>West to East. Let's use that.
Yeah, I messed that bit up!
> No. The speed of light in a vacuum is the same for all observers. I
> presume the vacuum as a part of your experiment.
I dont get the bit about the vacuum. If the speed of light is constant, why
does the vacuum come into the play?
> Yes the Doppler comes into play, but not the way you seem to think it
> works.
> Since the boat is traveling W to E, it is adding energy to the wave
> traveling in that direction.
>
> Thus the light-radio wave traveling in that same direction has a greater
> energy than the light-radio wave going the other way.
> Greater energy means a blue shift for light, a shift toward higher
> frequency for the radio wave.
> Thus the wave traveling in the same direction as the boats velocity,
> will arrive at the LA shore at the speed of light, but with a frequency
> shift toward slightly higher frequency (shorter wavelength, same thing).
> This is an example of the Dopples effect for electromagnetic waves.
Ok, I get that bit. Thanks
> But it will be way too smale to notice. If you really like I can
> calculate it for you.
Thanks for the offer. I am out of my league already.
Spad
> Here's a hypothetical question.
>
> A boat is sailing east to west across the pacific. Say, Tokyo to L.A (The
> distance is irrelevant, it could just be across a bay). The boat is
> travelling at ten knots. At the mid-way point, the boat transmits a message
> on the radio. We know that radio waves travel at the speed of light and for
> the sake of the argument the frequency used transmits ground waves.( I know
> the boat would really be using sky waves)
>
> Is the signal going to L.A. travelling at the speed of light plus ten knots
> and the signal going to Tokyo travelling at the speed of light less ten
> knots?
>
> Or does the Doppler effect come in to play. The signal travels at the speed
> of light in both directions but is slightly stronger at L.A. and weaker at
> Tokyo?
>
> Good Sailing and Fair Weather
>
> D Parker
This is an example of a perfectly irrelevant question that often permeates this
group. And, as usual, it generates some perfectly irrelevant responses, all of
which have absolutely nothing to do with sailing. Booorrrrrriinnngggg.
JES
Politeness Man
This is where we disagree. I can say with some degree of confidence
that c is constant in free space where there are no fields (gravity,
electric or otherwise), that the medium (whatever it is) that sustains
the propagation is not moving and the observers are not moving WRT to
the medium.
If light enters a medium without the above properties its velocity
changes. If the medium is denser in the properties that propagate the
light, the light goes faster. Less dense, it slows.
I really don't see the need to invent an "internal clock" in a photon
or claim that space, time and measurement distort with large masses.
For some odd reason I prefer the simplest of explanations especially
ones without contradiction. In light (good pun) of the results of the
Fizeau experiment, Michelson-Morley experiment I don't see how anyone
could not question the POSTULATE that light speed is constant. I also
don't see how anyone can claim that measurements made on the surface of
the earth (in the presence of gravity, its electric and magnetic field,
plasma field plus it is rotating) are representative of free space
conditions (please note physical clocks do run slower on earth than in
space, in fact their rate is inversely proportional to latitude).
If your beliefs serve as useful models for the work you do, it is fine.
Remember that they are equivalents and not the truth. Most of the
equivalents in SRT have no fundamental basis in reality, they do not
attempt to explain physical phenomena, at best they describe it.
A good scientist always works to disprove a theory (even if it is his
own). One single case showing contrary results to his theory disproves
the theory. If the speed of light is constant, regardless of the motion
of its source, why did Fizeau measure two velocities for light, one
against the water and one with the water? Why does light travel faster
in the presence of cesium gas? Does cesium gas affect the internal
clock of the photon? Does running water affect the internal clock of
the photon?
Politeness Man
In article <8ud4hr$rm6$1...@nnrp1.deja.com>,
Gilligan
For your edification I have a quote from a book. The book is by Albert
Einstein, it is titled: "Relativity The Special and the General". In
this book Mr. Einstein says on page 76:
"the curvature of rays of light can only take place when the velocity
of propagation of light varies with position. Now we might think that
as a consequence of this, the special theory of relativity and with it
the whole theory of relativity would be laid in the dust. But in
reality this is not the case. We can only conclude that the special
theory of relativity cannot claim an unlimited domain of validity; its
results hold only so long as we are able to disregard the influences of
gravitational fields on the phenomena (e.g. of light)."
Additionally on the same page:
"In the second place our results shows that, according to the general
theory of relativity, the law of the constancy of the velocity of light
in vacuo, which constitutes one of the two fundamental assumptions in
the special theory relativity and to which we have frequently referred,
cannot claim any unlimited validity."
Einstein states that the constancy of the speed of light in vacuo is an
assumption. He also claims it is not universally applicable. What is
most entertaining are the many "scientists" who do experiments to prove
the assumption that the speed of light is constant. They'll distort
time and space and lo and behold! Light speed is constant!
Nearby to you in New Guinea a tribe causes the sun to rise everyday by
beating their drums. Every dawn they beat them, the sun rises! Never
has been proven otherwise!
Gilligan, altering the speed of light for the benefit of all!
Marty
Dr...@mailroom.com wrote:
> This is an example of the Dopples effect for electromagnetic waves.
>
> But it will be way too smale to notice.
Not quite, too small to notice with your average SSB reciever, yes. But
easily measurable with equipment built for the purpose, for example
"radar" guns do measure doppler shifts caused by velocities less than
one mile per hour routinely.
Cheers
Marty
Douglas S. King
> ...(brief snip)...
> Einstein states that the constancy of the speed of light in vacuo is an
> assumption. He also claims it is not universally applicable. What is
> most entertaining are the many "scientists" who do experiments to prove
> the assumption that the speed of light is constant. They'll distort
> time and space and lo and behold! Light speed is constant!
And time travel becomes possible.
A side benefit of being able to suppress or amplify quanta waves (or as a
friend of mine likes to say "wavitons") along the Dt axis is that one can
travel faster than the speed of light, or indeed faster than
teleportation. Not actually, but you can simply go wherever you like at
whatever speed is convenient, then dial yourself back to the instant you
left.
> Nearby to you in New Guinea a tribe causes the sun to rise everyday by
> beating their drums. Every dawn they beat them, the sun rises! Never
> has been proven otherwise!
Well, many people grasp the principle of cause and effect, but miss the
little details like that the cause/effect is what it is, not what it
seems.
> Gilligan, altering the speed of light for the benefit of all!
Thanks very much.
BTW have you ordered my Christmas present yet?
Fresh Breezes- Doug King
--
This is what we look like when we're at our best:
http://recboats.hsh.com/45.htm
Marty
Gilligan <gilligan...@my-deja.com> wrote:
> Gilligan, altering the speed of light for the benefit of all!
>
Gilligan:
After you get the Nobel Prize in Physics for knocking the world of
physics on its rear by debunking SRT, GRT, and coming up with your own
GUT, will you be sharing the prize money with the members of this forum
who have sparked your intellect too such lofty hieghts?
Cheers
Marty
(it's to cold to sail up here:-(o)
Donal
> I don't quite see your problem or else the picture is unclear.
Very probably an unclear description.
> If the observer is beside you then you both detect the light
> flash at the same moment because the time taken for the light
> flash to get there is L/c where L is the distance to the
> flashlight. It does not matter that you are moving this just changes the
> *apparent* wavelength of the beam (because your movement contracts your
> measurement frame).
I wasn't wondering about *when* the light passed us, but at what speed. For
example we both have a one foot long "measuring" strip in our hand which can
magically measure the time difference between light hitting its leading and
trailing edge.
If I understand what has been said, then we would both register the same
speed for the light. But one of us is already going at half the speed of
light, therefore the speed measured is 1.5 times the speed of light relative
to the stationary person.
I hope that the question is clearer now, (but I am not confident).
Regards
Donal
--
Donal
Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0A23...@Armory.arm...
> Donal wrote:
> >
> > So, I am on a travelator that is travelling at 96,000 miles per second.
My
> > fellow scientist is in the corridor beside the travelator, and he is
> > stationary. Somebody on terra firma at the end of the travelator
swithes on
> > a torch. Do we both detect the light passing us at the same speed?
>
>
> Yes. But not at the saem time.
Then the light must be travelling at two different speeds, as one of us is
already moving at half the speed of light.
> >
> > If we do, then the light must be in two different places at the same
time.
> > Is this correct?
>
> No. It is in two different places at two unrelated times. And at two
> different colors.
I am a touch confused by "unrelated times". Surely one time must either
come before or after the other, and therefore the times must be related?
Regards
Donal
--
Gilligan
Time travel is not possible unless one considers a phone booth a time
travel machine. I will go in the phone booth and emerge in the future,
10 minutes from now. Enter the phone booth, wait ten minutes, step out.
Viola! Time travel! Real time travel is going backwards, then returning.
I would like very much like to get you a Christmas present. In fact, I
have been looking for a Knox Frigate model for you. They are a bit
pricey but I know you would enjoy it. Also I have a life boat sextant
here - all brass in a nice wooden case. It is cute, but not really
suitable for navigational purposes. Would you like that instead? It's a
nice desk piece.
What kind of engineer are you?
Gilligan
In article <3A0ADA07...@mindspring.com>,
> > Gilligan, altering the speed of light for the benefit of all!
>
> Thanks very much.
>
> BTW have you ordered my Christmas present yet?
>
> Fresh Breezes- Doug King
> --
> This is what we look like when we're at our best:
> http://recboats.hsh.com/45.htm
>
>
Gilligan
I am not refuting GTR. For the most part I do not refute SRT (depends
on whose version of it), I only apply it correctly and attempt to
understand it by real physical explanation. As you can see Einstein and
I are agreement on the nature of the velocity of light, what affects it
and the consequences in SRT. Knowledge of the fundamentals is very
important in bending nature to our will, otherwise we are just playing
by arbitrary (and misunderstood) rules.
Should I win the Nobel Prize, I will be eager to have it benefit
everyone . I will buy an AM radio transmitter station for the wise and
knowing Capt. Neal, who will broadcast his excellent knowledge to the
betterment of all. There can be no greater prize to humanity!
Gilligan
In article <8ueonf$5m8$1...@nnrp1.deja.com>,
Marty <baxt...@rmc.ca> wrote:
> In article <8uek02$10r$1...@nnrp1.deja.com>,
> Gilligan <gilligan...@my-deja.com> wrote:
>
> > Gilligan, altering the speed of light for the benefit of all!
> >
>
> Gilligan:
>
> After you get the Nobel Prize in Physics for knocking the world of
> physics on its rear by debunking SRT, GRT, and coming up with your own
> GUT, will you be sharing the prize money with the members of this
forum
> who have sparked your intellect too such lofty hieghts?
>
> Cheers
> Marty
> (it's to cold to sail up here:-(o)
>
Per Elmsäter
news:8uet3i$9sl$1...@nnrp1.deja.com...
> Should I win the Nobel Prize, I will be eager to have it benefit
> everyone . I will buy an AM radio transmitter station for the wise and
> knowing Capt. Neal, who will broadcast his excellent knowledge to the
> betterment of all. There can be no greater prize to humanity!
>
Gilligan that would be a great contribution to humanity and all sailors. I
do have some connections with the Nobel Prize Comittee in Stockholm. I'll
see what I can do for you.
--
The_navigator
As I understand it, radar guns do not measure Doppler shift (this is
probably too small to measure with simple equipment). They work by
measuring the time of flight of a radar pulse (which assumes a constant
c -GILLIGAN please note that next time you get a ticket!!!). The
differential of this signal wrt time is 'speed'.
Regards MC
In article <8uekge$1he$1...@nnrp1.deja.com>,
Marty <baxt...@rmc.ca> wrote:
> In article <3A0A21...@Armory.arm>,
> Dr...@mailroom.com wrote:
>
> > This is an example of the Dopples effect for electromagnetic waves.
> >
> > But it will be way too smale to notice.
>
> Not quite, too small to notice with your average SSB reciever, yes.
But
> easily measurable with equipment built for the purpose, for example
> "radar" guns do measure doppler shifts caused by velocities less than
> one mile per hour routinely.
>
> Cheers
> Marty
>
JAXAshby
>
>In a word yes.
>
>
>since light travels at 186,000 miles per sec
>
>the plus or minus of 10 knots which is approx 10 miles/hour or 10/3600
>=0.0027 miles per sec it is not going to Make any significant difference
>
>Whitebear
>
Nope. Wrong answer.
Douglas S. King
> Doug:
> Time travel is not possible unless one considers a phone booth a time
> travel machine. I will go in the phone booth and emerge in the future,
> 10 minutes from now. Enter the phone booth, wait ten minutes, step out.
> Viola! Time travel! Real time travel is going backwards, then returning.
You can do that if you fill the phone booth with lime Jell-O, duct tape
some aluminum foil in a big triangle or the top of it, and shine a "Gedi
Knight Lite SaberŽ" from K-Mart through the jello. Oh wait I forgot, you
also have to duct tape a Casio digital watch to the phone booth to set the
time you want to travel to.....
> I would like very much like to get you a Christmas present. In fact, I
> have been looking for a Knox Frigate model for you. They are a bit
> pricey but I know you would enjoy it.
That's very thoughtful, as you probably know I rode around a Knox class tin
can for a few years. They are funny-looking with that stack, though; if I
may be presumptuous how about a Farragut class DLG instead?
> Also I have a life boat sextant
> here - all brass in a nice wooden case. It is cute, but not really
> suitable for navigational purposes. Would you like that instead? It's a
> nice desk piece.
Save that one for Babs, she needs it more than I do ;)
I have your gift all picked out too, it's an Aspidochilone, which I figure
will come in mighty handy around the ol' Island. Not sure how to wrap it,
though.
> What kind of engineer are you?
What, don't you already know? Next you'll be telling me you don't know
which Knox class boat I was on. Didn't you ask my old buddies at Camp Perry
all about me.......
For the record, I have a BSME from a major university (I'm sure you know
which one, if not ask larry flint) and my card reads "Metrology Consultant
& Junior Rocket Scientist."
JAXAshby
>moves independently of the observer or the source.
>
Sailor Al Einstein did not prove that at all. Others proved that before him.
A 23 year old Al ran the "what if's" against that and came up with "The Special
Theory Of Relativity".
JAXAshby
>questions. If Einstien did not postulate it then Lorentz soon would
>have.
be quiet, game boy. It is obvious already that you know from diddly about this
subject.
JAXAshby
>inertial frame (a rotating reference frame, the earth, - an accelerated
>reference frame) and the velocities add. The has been demonstrated for
>decades using satellites, ground radio waves and light.
>
>Gilligan
>
Jill, join game boy in the corner.
The_navigator
You ignore what I said earlier. I did not claim tha the speed of light
is constant, I said it is constant where the medium it passes through
has a constant refractive index.
In fact I said:
"Newbies, please note, that in a medium of constant refractive index the
speed of light does not vary!" and now you reiterate what I said (this
is very annoying).
It is also possible for particles to travel above the speed of light in
a medium with refractive index grater than vacuo. The statement from
Eistein is well known and was, I believe, a part of his 'shame' which
he regretted deeply later. The caveat (which was completely unecessary)
was placed there so as not to offend since it was not possible by
xperiment to show that LIGHT can travel faster than light in vacuo. Now
the point is simply that the speed of light is constant, but that space
and time are not. Within any inertial frame the speed of light is
constant regardless of the observer position in that inertial frame.
What changes with velocity and gravitiation are the dimensions of
SPACE/TIME It is not that c has changed, it is a universal constant
just as pi is.
The energy of a photon is hv = 0.5 mc^2 (h= Planck's constant v is
frequency m is apparent mass and c, the speed of light is a constant)
Hence at all times: v=k.m where k is a constant and m the apparent mass
of the photon. It follows that any _apparent_ change in velocity of the
photon (due to the observer moving) is manifest not by c changing but by
the frequency of the photon changing. Frequency is reciprocal TIME. Do
you understand? If you think about it, does this help you undertsand why
I was talking about the 'photon's clock'. This is the actual period of
the electromagnetic wave, not the period observed -which depends on the
observers clock (which runs slower in a gravity field).
Now gravity bends light not by changing the velocity of light (as is the
case of a lens) but by changing SPACE. Within an interial frame the
light travels in a straight line, but the inertial frame containing the
photon moves into a gravity fields and changes it's path. The inertial
frame must follow the curvature of space (since it is, by definition an
INERTIAL frame which will continue to move in a straight line unless
acted upon by a force -this is of course a link to Newtonian physics)
and since space-time is disported by gravity the inertial frame moves
from it's straight path (what ever straight really means in a mass
containing universe !!!). This causes the photon path to bend for an
observer -not because the photon itself is bending its path but because
of space time curvature.
Do you see this or do you not agree?
Now where is Useless when you need him!
As to your questions, it is not light that travels faster than c in the
'caesium gas' experiment. This is a demonstration of a problem of time
measurement. When you start with a very short pulse it is easy to
measure it's time of occurance. As the pulse is stetched by the medium
you have to change your point of measurement. In this case the
experimenters chose the leading edge, but had they chosen the trailing
edge the pulse would have travelled at less than c in that medium. It is
important for you to try to understand that the GROUP VELOCITY was the
speed of light in that medium, no more and no less. I think of this
particular Nature paper as a bit of a parlor game and not at all
important. It is far less suprising than Cherenkov radiation (for
example). As to measuring an effect of effect of water flow, I was
under the impression that Fitzeau in 1849 had shown that the speed of
light was quite constant... What is this experiment to which you are
referring (at that time near relativistic effects would have not been
measureable)?
Cheers MC
In article <8uek02$10r$1...@nnrp1.deja.com>,
Gilligan <gilligan...@my-deja.com> wrote:
> Navigator:
> For your edification I have a quote from a book. The book is by Albert
> Einstein, it is titled: "Relativity The Special and the General". In
> this book Mr. Einstein says on page 76:
>
> "the curvature of rays of light can only take place when the velocity
> of propagation of light varies with position. Now we might think that
> as a consequence of this, the special theory of relativity and with it
> the whole theory of relativity would be laid in the dust. But in
> reality this is not the case. We can only conclude that the special
> theory of relativity cannot claim an unlimited domain of validity; its
> results hold only so long as we are able to disregard the influences
of
> gravitational fields on the phenomena (e.g. of light)."
>
> Additionally on the same page:
>
> "In the second place our results shows that, according to the general
> theory of relativity, the law of the constancy of the velocity of
light
> in vacuo, which constitutes one of the two fundamental assumptions in
> the special theory relativity and to which we have frequently
referred,
> cannot claim any unlimited validity."
>
> Einstein states that the constancy of the speed of light in vacuo is
an
> assumption. He also claims it is not universally applicable. What is
> most entertaining are the many "scientists" who do experiments to
prove
> the assumption that the speed of light is constant. They'll distort
> time and space and lo and behold! Light speed is constant!
> Nearby to you in New Guinea a tribe causes the sun to rise everyday by
> beating their drums. Every dawn they beat them, the sun rises! Never
> has been proven otherwise!
>
> Gilligan, altering the speed of light for the benefit of all!
>
Dr Arm®
>
> Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0A23...@Armory.arm...
> > Donal wrote:
> > >
> My
> > > fellow scientist is in the corridor beside the travelator, and he is
> > > stationary. Somebody on terra firma at the end of the travelator
> swithes on
> > > a torch. Do we both detect the light passing us at the same speed?
> >
> >
> > Yes. But not at the saem time.
>
> already moving at half the speed of light.
>
No. The light travels with the same speed for all the observers.
The clocks are different. They mark time differently.
You cannot have a defination of "simutaneous" for two different inertial
frames moving with respect to each other. Sound sufficiently strange
yet? :)
da
> > >
> > > If we do, then the light must be in two different places at the same
> time.
> > > Is this correct?
> >
> > No. It is in two different places at two unrelated times. And at two
> > different colors.
>
Dr Arm®
>
> "Dr ArmŽ" <Ar...@Armory.arm> wrote in message news:3A0A21...@Armory.arm...
>
> snip
>
> >West to East. Let's use that.
> Yeah, I messed that bit up!
>
> > No. The speed of light in a vacuum is the same for all observers. I
> > presume the vacuum as a part of your experiment.
>
> I dont get the bit about the vacuum. If the speed of light is constant, why
> does the vacuum come into the play?
It is the speed of light in a vacuum that is the fundamental physical
constant. Lightspeed is different in air, water, quartz and always
slower than in a vacuum. But for the effect you are trying to understand
the speed in a vacuum is a fine enough approiximation.
Here, maybe I can confuse you a bit more: nothing can exceed the speed
of light in a vacuum. But you can exceed the speed of light in, say,
water. Light moves through water slower than it moves through a vacuum.
MAybe ten percent slower.
Particles emitted from a reactor can move through the cooling water
faster than light moves through the water.
Analogous to a sonic boom, these fast moving particles create a
beautiful blue glow of radiated lightwaves called Cherenkov Radiation.
da
>
> > Yes the Doppler comes into play, but not the way you seem to think it
> > works.
> > Since the boat is traveling W to E, it is adding energy to the wave
> > traveling in that direction.
> >
> > Thus the light-radio wave traveling in that same direction has a greater
> > energy than the light-radio wave going the other way.
> > Greater energy means a blue shift for light, a shift toward higher
> > frequency for the radio wave.
> > Thus the wave traveling in the same direction as the boats velocity,
> > will arrive at the LA shore at the speed of light, but with a frequency
> > shift toward slightly higher frequency (shorter wavelength, same thing).
> > This is an example of the Dopples effect for electromagnetic waves.
>
> Ok, I get that bit. Thanks
>
> > But it will be way too smale to notice. If you really like I can
> > calculate it for you.
>
> Thanks for the offer. I am out of my league already.
>
Dr Arm®
>
> d parker wrote:
>
> > Here's a hypothetical question.
> >
>
> group. And, as usual, it generates some perfectly irrelevant responses, all of
> which have absolutely nothing to do with sailing. Booorrrrrriinnngggg.
>
And it does so at nearly the speed of light! :)
da
> JES
Dr Arm®
>
> Sailor Al Einstein did not prove that at all.
What a dummy you are Juiceboy. Sober up and go back to school, that
ninth grade education does not seem to be getting you anywhere.
Dr Arm®
>
> Gilligan
>
> You ignore what I said earlier. I did not claim tha the speed of light
> is constant, I said it is constant where the medium it passes through
> has a constant refractive index.
> In fact I said:
> "Newbies, please note, that in a medium of constant refractive index the
> speed of light does not vary!" and now you reiterate what I said (this
> is very annoying).
>
> It is also possible for particles to travel above the speed of light in
> a medium with refractive index grater than vacuo.
IS there such a medium? I don't think so.
AE's theories do not rule out faster than light speed (in a vacuum)
travel, and the class of particles that can do this is called tachyons,
but they have never sbeen shown to exist (AFAIK). At any rate, they
would not be able to slow down to lightspeed any more than a real
particle can accelerate up to lightspeed.
The statement from
> Eistein is well known and was, I believe, a part of his 'shame' which
> he regretted deeply later.
Maybe, but I never heard this. Perhaps you are referring to his
"blunder" of a force to prevent the universe from expanding?
> As to your questions, it is not light that travels faster than c in the
> 'caesium gas' experiment. This is a demonstration of a problem of time
> measurement. When you start with a very short pulse it is easy to
> measure it's time of occurance. As the pulse is stetched by the medium
> you have to change your point of measurement. In this case the
> experimenters chose the leading edge, but had they chosen the trailing
> edge the pulse would have travelled at less than c in that medium. It is
> important for you to try to understand that the GROUP VELOCITY was the
> speed of light in that medium, no more and no less. I think of this
> particular Nature paper as a bit of a parlor game and not at all
> important.
Have you seen the tunneling experiment wherein inforamtion traveled
faster than light?
It appears that tuneling results in travel from point A to point B
faster than a beam of light could make the trip. A german investigation
added modulation to the tuneling and apears to get a faster than light
transmission.
da
Dr Arm®
>
> Gilligan wrote:
>
> > ...(brief snip)...
> > assumption. He also claims it is not universally applicable. What is
> > most entertaining are the many "scientists" who do experiments to prove
> > the assumption that the speed of light is constant. They'll distort
> > time and space and lo and behold! Light speed is constant!
>
That's quite a far fetched jump. Time dialation and time travel are two
quite different things. Though time may dialate and approach zero, it
has not been shown that it can actually reverse. More likely are the
reverse time travel direction of EM waves: The "spooky action at a
distance" does seem to have validity.
>
> A side benefit of being able to suppress or amplify quanta waves (or as a
> friend of mine likes to say "wavitons") along the Dt axis is that one can
> travel faster than the speed of light, or indeed faster than
> teleportation. Not actually, but you can simply go wherever you like at
> whatever speed is convenient, then dial yourself back to the instant you
> left.
You need to patent this quick!
> > Nearby to you in New Guinea a tribe causes the sun to rise everyday by
> > beating their drums. Every dawn they beat them, the sun rises! Never
> > has been proven otherwise!
They have their science and we have ours. The value you extract from a
philosophy is the predictions you can make based on it. I suspect the
drum beating theory breaks down somewhere just beyond the sunrise
outcome.
da
>
> Well, many people grasp the principle of cause and effect, but miss the
> little details like that the cause/effect is what it is, not what it
> seems.
>
> > Gilligan, altering the speed of light for the benefit of all!
>
> Thanks very much.
>
> BTW have you ordered my Christmas present yet?
>
Gilligan
My replies are below.
> Gilligan
>
> You ignore what I said earlier. I did not claim tha the speed of light
> is constant, I said it is constant where the medium it passes through
> has a constant refractive index.
> In fact I said:
> "Newbies, please note, that in a medium of constant refractive index
the
> speed of light does not vary!" and now you reiterate what I said (this
> is very annoying).
The speed of light is constant to the medium of constant permitivitty,
however if the medium is placed in an accelerated reference frame -
gravitational or motional the velocity of light changes. Also if the
field of the photon extends beyond the medium (as in single mode unclad
fiber optic cable) the velocity also changes.
>
> It is also possible for particles to travel above the speed of light
in
> a medium with refractive index grater than vacuo. The statement from
> Eistein is well known and was, I believe, a part of his 'shame' which
> he regretted deeply later. The caveat (which was completely
unecessary)
> was placed there so as not to offend since it was not possible by
> xperiment to show that LIGHT can travel faster than light in vacuo.
Now
> the point is simply that the speed of light is constant, but that
space
> and time are not. Within any inertial frame the speed of light is
> constant regardless of the observer position in that inertial frame.
> What changes with velocity and gravitiation are the dimensions of
> SPACE/TIME It is not that c has changed, it is a universal constant
> just as pi is.
So then does light speed depend on the gravitational vector? I mean
does light travelling tangential to the earth's surface move at a
different velocity than perpindicular to the earth's surface? I agree
with the inertial observations but I strongly disagree with the
space/time distortion. I will explain why later.
>
> The energy of a photon is hv = 0.5 mc^2 (h= Planck's constant v is
> frequency m is apparent mass and c, the speed of light is a constant)
> Hence at all times: v=k.m where k is a constant and m the apparent
mass
> of the photon. It follows that any _apparent_ change in velocity of
the
> photon (due to the observer moving) is manifest not by c changing but
by
> the frequency of the photon changing. Frequency is reciprocal TIME. Do
> you understand? If you think about it, does this help you undertsand
why
> I was talking about the 'photon's clock'. This is the actual period of
> the electromagnetic wave, not the period observed -which depends on
the
> observers clock (which runs slower in a gravity field).
I understand this. I also understand that the photons "clock" is the
field of the photon extending into the space surrounding it. The field
also carries the energy of the photon. When the photon has energy added
to it or subtracted it will change its frequency accordingly. The
photon is reacting to external conditions.
>
> Now gravity bends light not by changing the velocity of light (as is
the
> case of a lens) but by changing SPACE. Within an interial frame the
> light travels in a straight line, but the inertial frame containing
the
> photon moves into a gravity fields and changes it's path. The inertial
> frame must follow the curvature of space (since it is, by definition
an
> INERTIAL frame which will continue to move in a straight line unless
> acted upon by a force -this is of course a link to Newtonian physics)
> and since space-time is disported by gravity the inertial frame moves
> from it's straight path (what ever straight really means in a mass
> containing universe !!!). This causes the photon path to bend for an
> observer -not because the photon itself is bending its path but
because
> of space time curvature.
>
> Do you see this or do you not agree?
I see this as it is - an equivalence. I still maintain that light speed
varies as a function of gravitational potential (as Einstein did too).
That is why it bends in a gravity field. It would also follow that
light travelling normal to the earths surface would experience a
velocity change with no bending in the path. When the energy input from
the gravity field also changes its frequency. This is confirmed by
those particle decay-density experiments conducted at multiple
altitudes. Your space/time distortions will yield the same results with
much greater complexity than my methods. I choose the simpler one.
>
> Now where is Useless when you need him!
Uysless would certainly spice things up.
>
> As to your questions, it is not light that travels faster than c in
the
> 'caesium gas' experiment. This is a demonstration of a problem of time
> measurement. When you start with a very short pulse it is easy to
> measure it's time of occurance. As the pulse is stetched by the medium
> you have to change your point of measurement. In this case the
> experimenters chose the leading edge, but had they chosen the trailing
> edge the pulse would have travelled at less than c in that medium. It
is
> important for you to try to understand that the GROUP VELOCITY was the
> speed of light in that medium, no more and no less. I think of this
> particular Nature paper as a bit of a parlor game and not at all
> important. It is far less suprising than Cherenkov radiation (for
> example).
I agree. Group velocity is sheninagans. This was also known for
decades.
As to measuring an effect of effect of water flow, I was
> under the impression that Fitzeau in 1849 had shown that the speed of
> light was quite constant... What is this experiment to which you are
> referring (at that time near relativistic effects would have not been
> measureable)?
Fizeau showed that water speed was added to the light speed. Einstein
discussed this in his book "Relativity" and comments that the
electromagnetic methods were simpler and provided insight.
Now here's the crux: Your methods are fine and will yield good results
when applied correctly. However you are missing the most fundamental
aspect. It is the definition, nature and measurement of time. First and
utmost, time is an abstraction. Time is the sequence of events when
they occur. Time is a universal and a primitive, fundamental concept.
All this space/time distortion is an attempt to account for the
transmittance or the measurement of a material representation of time.
It is not the abstraction of time. If one holds time as an absolute
measurement (yet realizing that the measurement of time by instruments
is affected by the environment) one can conclude that velocity and
lengths change.
This logic of the distortion of time is erroneous. If I go to France
and cut the standard meter in half, will everyone's shoe sizes double?
Will all of our feet have grown? Of course not. But then - can I
conclude by cutting the meter in half that I caused everyone's
speedometer to double in speed? No, So then I must conclude that by
cutting the meter in half I caused everyone's clocks to slow down
because the speedometers read faster for the same events. Yes this is
silly, but so is the bending of time and space.
Time is a universal, it does not conceptually change (it is a sequence
of events). The measurement of time is affected by the environment. In
space, as throughout the universe light speed is affected by gravity,
and other fields. These changes in speed cause it to bend (refraction)
and can add or subtract energy from it, changing its frequency. If you
define time as some physical quantity it will be affected by nature.
Remember you are changing the measurement, not the abstraction.
On a contemplative note, if the big bang really did happen and the
universe is flying apart at speeds greater than my Bucaneer can
achieve, and the amount of matter is fixed - then one concludes the
universe is becoming less dense. As it becomes less dense the speed of
light must be slowing down. With this in mind, the light from the
furthest stars must have travelled the longest period and experienced
the most slowing. They have the greatest red shift. Is the red shift
due to the velocity of the source or the slowing of light?
Gilligan, the alternative to equivalence!
Gilligan
I have never considered the jello or sabrelights. I think it will work,
we should collaborate on this great concept. We must beware of spy rays.
If we perfect this device, I propose sending the good Capt. Neal into
the past so he can straighten things out when they first needed it. He
would return a hero!
Why wouldn't you want a Knox class frigate? They were the pride of the
fleet. They had many features for the comfort and safety of the crew.
The turbines didn't poke up into the crews mess, control booth in the
engine room had a great view, the diesel auxiliary power was away from
the bunks, and later models even had spray strakes! Are you sure you
don't want a replica of this sea worthy battle wagon?
Whats wrong with the sextant? Christmas is coming up fast and now I
must rush to find you a proper gift. Do you like smoked game meat? I
just got the Cabelas Christmas edition. They have a wonderful reptile
sampler - bet it reminds you of your southern roots. Weee doggy -
possum innards and hog renderins'.
What's an ME doing in metrology? You should be out designing stuff -
manly stuff such as big molds, progressive dies, rocket motor mounts,
bridges, earth moving equipment!
Here comes ol' Billy C
You can hear dem shufflin' feet
He would rather toke than eat -
And that's what I like about the South
Ham hocks and buttered beans-
Madi Gras in New Orleans -
That's what I like about the South!
Gilligan
Donal
Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0BB7...@Armory.arm...
> Donal wrote:
> >
>
> No. The light travels with the same speed for all the observers.
>
> The clocks are different. They mark time differently.
>
> You cannot have a defination of "simutaneous" for two different inertial
> frames moving with respect to each other. Sound sufficiently strange
> yet? :)
>
I am not sure where these different inertial frames have suddenly appeared
from. All three participants in my experiment started off together. One
rapidly accelerated to half the speed of light. I assume that he, and the
light that he measures, are now in a different "inertial frame". At what
speed did they change inertial frames? Or do we all occupy different
inertial frames?
I find the whole concept of time passing at different speeds, space
curvature etc. to be the result of extreme contortions of logic. It seems
that just because a "Genius" said so, that we all believe it, or are afraid
to say 'b*ll*cks' in case people think that we are a bit thick. At any
given point of history, man has thought that he understood the universe.
And yet every 10 years our understanding changes. We are just Not very
bright.
My opinion is, that if you do not really understand the concept of the
constancy of the speed of light relative to the observer, and all its
implications, then you should not believe it. Do not think that these
theories are right because some scientists said so.
Time IS constant. Space does NOT bend. The reason that nobody has
convinced me otherwise is not that I am too thick, it is because they are
wrong.
Regards
Donal
--
Marty
The_navigator <the_na...@my-deja.com> wrote:
> Dear Marty
>
> As I understand it, radar guns do not measure Doppler shift (this is
> probably too small to measure with simple equipment). They work by
> measuring the time of flight of a radar pulse (which assumes a
constant
> c -GILLIGAN please note that next time you get a ticket!!!). The
> differential of this signal wrt time is 'speed'.
>
MC:
You may well be correct, I'll have to look into it. This would of
course mean measuring the time of flight of sucsessive pulses and
computing the speed of the target based on the shortening of the flight
times.
Cheers
Marty
Capt. Ahab
Gilligan
Pure bunk!
Why then does one check the accuracy of a radar gun by reflecting the
signal from a a tuning fork?
A radar gun is a homodyne receiver, it measures doppler shift. The
audio tuning fork, used to calibrate the gun, corresponds to the
doppler shift for a given speed. Light speed does vary over the surface
of the earth. In fact optical systems exist that can measure indexes of
refraction to 6 decimal places. The slightest changes in the atmosphere
cause changes in the speed of light. That's why there's such things as
coherence length and one use of confluent hypergeometric series.
If MC doesn't know how a radar gun works, how can he be sure space
(whatever that is) and time distort so light speed is ever constant?
Gilligan
In article <8uf65e$i6k$1...@nnrp1.deja.com>,
The_navigator <the_na...@my-deja.com> wrote:
> Dear Marty
>
> As I understand it, radar guns do not measure Doppler shift (this is
> probably too small to measure with simple equipment). They work by
> measuring the time of flight of a radar pulse (which assumes a
constant
> c -GILLIGAN please note that next time you get a ticket!!!). The
> differential of this signal wrt time is 'speed'.
>
> Regards MC
>
> In article <8uekge$1he$1...@nnrp1.deja.com>,
> Marty <baxt...@rmc.ca> wrote:
> > In article <3A0A21...@Armory.arm>,
> > Dr...@mailroom.com wrote:
> >
> > > This is an example of the Dopples effect for electromagnetic
waves.
> > >
> > > But it will be way too smale to notice.
> >
> > Not quite, too small to notice with your average SSB reciever, yes.
> But
> > easily measurable with equipment built for the purpose, for example
> > "radar" guns do measure doppler shifts caused by velocities less
than
> > one mile per hour routinely.
> >
> > Cheers
> > Marty
> >
Gilligan
http://www.copradar.com/preview/chapt3/ch3d1.html
Gilligan, doppler shifted, not timed
bob
they are having a discussion about windmills...
"d parker" <davep...@optusnet.com.au> wrote in message
news:3a0938a8$0$19415$7f31...@news01.syd.optusnet.com.au...
> Here's a hypothetical question.
>
> A boat is sailing east to west across the pacific. Say, Tokyo to L.A (The
> distance is irrelevant, it could just be across a bay). The boat is
> travelling at ten knots. At the mid-way point, the boat transmits a
message
> on the radio. We know that radio waves travel at the speed of light and
for
> the sake of the argument the frequency used transmits ground waves.( I
know
> the boat would really be using sky waves)
>
> Is the signal going to L.A. travelling at the speed of light plus ten
knots
> and the signal going to Tokyo travelling at the speed of light less ten
> knots?
>
> Or does the Doppler effect come in to play. The signal travels at the
speed
> of light in both directions but is slightly stronger at L.A. and weaker at
> Tokyo?
Dr Arm®
>
> Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0BB7...@Armory.arm...
> > Donal wrote:
> > >
> >
> > No. The light travels with the same speed for all the observers.
> >
> > The clocks are different. They mark time differently.
> >
> > You cannot have a defination of "simutaneous" for two different inertial
> > frames moving with respect to each other. Sound sufficiently strange
> > yet? :)
> >
>
> I am not sure where these different inertial frames have suddenly appeared
> from.
As soon as they are moving wrt each other they have their own inertial
frames.
All three participants in my experiment started off together. One
> rapidly accelerated to half the speed of light. I assume that he, and the
> light that he measures, are now in a different "inertial frame". At what
> speed did they change inertial frames?
Yes. As soon as he aquired a defferent velocity.
Or do we all occupy different
> inertial frames?
If they are moving together then the are in the same frame of reference.
It's only adding a coordinate system to each person in the experiment.
They could all have different IF's and still be traveling together, but
in order to track them physically we give them each a coordinate system.
Two ships passing have two different cordinate systems on their decks.
But they share the same coordinate system of the ocean.
>
> I find the whole concept of time passing at different speeds, space
> curvature etc. to be the result of extreme contortions of logic. It seems
> that just because a "Genius" said so, that we all believe it, or are afraid
> to say 'b*ll*cks' in case people think that we are a bit thick.
No there's validity for it.
A mu meson has a lifetime of about a microsecond.
It takes about 10 microseconds for one to reach the ground from where
they originate in the high atmosphere.
Yet most mu mesons make it to the ground.
Why? Because the stopwatch that we have on the ground says 10
microseconds, but because they are moving at close to lightspeed, the mu
mesons only think about a half microsecond has passed. So most hit the
ground.
It isn't a "manner of speaking" or a "physicist's trick of accounting"
that causes time to appear to pass differently to different observers
moving wrt each other.
It seems to be a real effect, a property of the universe that we live
in.
At any
> given point of history, man has thought that he understood the universe.
> And yet every 10 years our understanding changes. We are just Not very
> bright.
I don't think thiis is the case. Nobody claims to understand the
universe. Certain models of the universe seem to work in certain
applications: That is what being knowledgeable, educated, is really
about, when to apply which model. You don't yell at your child for
hitting a homer and you don't use the wave model when the particle model
applies!
> My opinion is, that if you do not really understand the concept of the
> constancy of the speed of light relative to the observer, and all its
> implications, then you should not believe it. Do not think that these
> theories are right because some scientists said so.
Of course not. But if you need to make a prediction of where the rocket
will land you have to use an appropiate physical model. Do you want to
account for the difference in the pulses of a cesium clock taken up 100
feet in a tower, then you can't say it's because you forgot to wind it.
:) OK you can say that but you won't be relied upon after saying you
lost the wind-up key. :) Einstein says it's different because the
gravitational field 100 feet up has less effect on slowing it down than
the same clock on the ground. Time passes slower in a stronger
gravatational field.
Our facination with time came from a need to navigate the oceans. It's
easy to determine latitude, but longitude is another problem altogether.
The British Admiralty offered a prize for the design of a clock that
would keep accurate time even on a pitching ship at sea. Now we can look
for the differences of the few picoseconds that might pass differently
because you flew a jetliner at 500 mph.
> Time IS constant. Space does NOT bend.
To someone moving slowly, then yes, of course, but tt's not and it does.
Consider a star who's position is well known and at this moment is
behind the sun.
But (during the darkness of an eclipse) that star is clearly visable and
not obscured by ol' sol. Because the light ray from the star was bent
toward the sun as it went past it and then ended up in our eye. A bit if
a curve as it went by the sun.
Astronomers see objects behind other large objects because the light is
bent back towards our view.
The reason that nobody has
> convinced me otherwise is not that I am too thick, it is because they are
> wrong.
OK, but now you're starting to sound a bit like Jaxby. Remember, he
graduated from the eighth grade. :)
da
>
> Regards
>
> Donal
> --
Dr Arm®
>
> Dear Marty
>
> As I understand it, radar guns do not measure Doppler shift (this is
> probably too small to measure with simple equipment). They work by
> measuring the time of flight of a radar pulse (which assumes a constant
> c -GILLIGAN please note that next time you get a ticket!!!). The
> differential of this signal wrt time is 'speed'.
Garden-variety radar measures time of flight.
Doppler radar measures Doppler shift, small though it is.
Thus it is possible to see a rainstorm with conventional radar. Doppler
radar will tell you which direction it is revolving.
da
>
> Regards MC
>
> In article <8uekge$1he$1...@nnrp1.deja.com>,
> Marty <baxt...@rmc.ca> wrote:
> > In article <3A0A21...@Armory.arm>,
> > Dr...@mailroom.com wrote:
> >
> > > This is an example of the Dopples effect for electromagnetic waves.
> > >
> > > But it will be way too smale to notice.
> >
> > Not quite, too small to notice with your average SSB reciever, yes.
> But
> > easily measurable with equipment built for the purpose, for example
> > "radar" guns do measure doppler shifts caused by velocities less than
> > one mile per hour routinely.
> >
> > Cheers
> > Marty
> >
d parker
to communicate. At this point you need to understand radio propagation. The
more one can learn about the subject the better.
Good Sailing and Fair Weather
D Parker
"Spad" <Spa...@att.net> wrote in message news:3A0AC1F9...@att.net...
Snip
> This is an example of a perfectly irrelevant question that often
permeates this
> group. And, as usual, it generates some perfectly irrelevant responses,
all of
> which have absolutely nothing to do with sailing. Booorrrrrriinnngggg.
>
> JES
>
>
>
Donal
Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0CD7...@Armory.arm...
> Donal wrote:
> >
>
> Or do we all occupy different
> > inertial frames?
>
> If they are moving together then the are in the same frame of reference.
> It's only adding a coordinate system to each person in the experiment.
> They could all have different IF's and still be traveling together, but
> in order to track them physically we give them each a coordinate system.
> Two ships passing have two different cordinate systems on their decks.
> But they share the same coordinate system of the ocean.
There seems to be a bit of "doublethink" creeping in here. The two ships
are occupying the same inertial frame and in two inertial frames at the same
time. So, can we measure their relative speeds, or not? Or can we simply
not measure the speed of an object on one ship relative to the speed on the
other ship?
These questions may seem ignorant, because the answers are obvious. But, if
we accept that these mesurements are possible, then the big question comes
back - at what point does it become impossible to make such comparisoms? We
either have to say that at a certain relative speed, the time frames make
measurements impossible, or we say that things drift apart. Neither option
can make any sense. I cannot define the boundary conditions between one
situation and the other.
>
>
> A mu meson has a lifetime of about a microsecond.
>
> It takes about 10 microseconds for one to reach the ground from where
> they originate in the high atmosphere.
> Yet most mu mesons make it to the ground.
>
> Why? Because the stopwatch that we have on the ground says 10
> microseconds, but because they are moving at close to lightspeed, the mu
> mesons only think about a half microsecond has passed. So most hit the
> ground.
>
It is also possible, (because we cannot measure anything beyond the speed of
light) that we *assume* that the muon is travelling at less than the speed
of light. AFAIK, the only evidence that they survive for 10, (or 50) uS, is
that that length of time would be required for that distance to be covered
at a speed approaching the speed of light. What would happen if the muon
were travelling at 5 (or 25) times the speed of light?
If we remove the obstacle, (which we created,) that says that nothing can
travel at greater than the speed of light, then we can make sense of the
universe using newtonian physics.
> It isn't a "manner of speaking" or a "physicist's trick of accounting"
> that causes time to appear to pass differently to different observers
> moving wrt each other.
>
> It seems to be a real effect, a property of the universe that we live
> in.
Most of which can also be explained by lifting the "false" ceiling - the
speed of light.
<snip>
> > Do not think that these
> > theories are right because some scientists said so.
>
> Of course not. But if you need to make a prediction of where the rocket
> will land you have to use an appropiate physical model. Do you want to
> account for the difference in the pulses of a cesium clock taken up 100
> feet in a tower, then you can't say it's because you forgot to wind it.
> :) OK you can say that but you won't be relied upon after saying you
> lost the wind-up key. :) Einstein says it's different because the
> gravitational field 100 feet up has less effect on slowing it down than
> the same clock on the ground. Time passes slower in a stronger
> gravatational field.
Perhaps caesium is simply affected by gravity and/or forces of acceleration?
Certainly, any observable physical oscillations of objects with mass are
affected by gravity and acceleration. Why should the innard of a caesium
atom be any different?
<snip>
> Consider a star who's position is well known and at this moment is
> behind the sun.
>
> But (during the darkness of an eclipse) that star is clearly visable and
> not obscured by ol' sol. Because the light ray from the star was bent
> toward the sun as it went past it and then ended up in our eye. A bit if
> a curve as it went by the sun.
>
> Astronomers see objects behind other large objects because the light is
> bent back towards our view.
>
I don't see any problem with this at all. Chuck anything past the sun and
its path will be deflected. Why try to make it complicated? I can see that
the path of light will bend as it goes past a large gravitational source,
without bending time and space. Light simply needs to have certain
properties of mass.
>> The reason that nobody has
> > convinced me otherwise is not that I am too thick, it is because they
are
> > wrong.
>
> OK, but now you're starting to sound a bit like Jaxby. Remember, he
> graduated from the eighth grade. :)
I may not have Jaxby's IQ, but I have read, and tried to understand, your
post. So to judge me relative to Jaxby is not valid, as I think that we
must exist in different inertial frames.
BTW. Thanks for taking the time to write the post. I did learn something
while reading it, even if I have not moved much from my position.
Regards
Donal
--
Douglas S. King
> Doug:
>
> I have never considered the jello or sabrelights. I think it will work,
> we should collaborate on this great concept. We must beware of spy rays.
> If we perfect this device, I propose sending the good Capt. Neal into
> the past so he can straighten things out when they first needed it. He
> would return a hero!
Return? Return? heh heh heh
> Why wouldn't you want a Knox class frigate? They were the pride of the
> fleet. They had many features for the comfort and safety of the crew.
> The turbines didn't poke up into the crews mess, control booth in the
> engine room had a great view, the diesel auxiliary power was away from
> the bunks, and later models even had spray strakes! Are you sure you
> don't want a replica of this sea worthy battle wagon?
Okay, you talked me into it. I could have a lot of fun inviting my friends
over to light off the fire room and play with the Hagan control board. The
bubble seat in a the 5"/54 is a hoot too. Will you come over and fix the
hydraulics and HP air occasionally?
> Whats wrong with the sextant? Christmas is coming up fast and now I
> must rush to find you a proper gift. Do you like smoked game meat? I
> just got the Cabelas Christmas edition. They have a wonderful reptile
> sampler - bet it reminds you of your southern roots. Weee doggy -
> possum innards and hog renderins'.
You must be thinking of someplace else, in the South we don't eat reptiles.
Oh wait, they eat armadilloes in Florida but is that really part of the
South?
> What's an ME doing in metrology?
Making lots of money, thanks. Actually I only straw-boss our cal lab, my
real job is parsing contracts and staring down bonehead subcontractors.
That's why I have so much free time on the computer most days.......
> Here comes ol' Billy C
> You can hear dem shufflin' feet
> He would rather toke than eat -
> And that's what I like about the South
>
> Ham hocks and buttered beans-
> Madi Gras in New Orleans -
> That's what I like about the South!
Mobile has a better Mardi Gras.
And what I like about the South is real barbeque. I also get a laugh out of
asking all the newly arrived Yankees "So, it it hot enough for you?" and
hearing them complain how much their air-conitioning costs and about
Southern drivers (who are all newly-arrived Yankees of course).
Dr Arm®
>
> Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0CD7...@Armory.arm...
> > Donal wrote:
> > >
> >
> > Or do we all occupy different
> > > inertial frames?
> >
> > If they are moving together then the are in the same frame of reference.
> > It's only adding a coordinate system to each person in the experiment.
> > They could all have different IF's and still be traveling together, but
> > in order to track them physically we give them each a coordinate system.
> > Two ships passing have two different cordinate systems on their decks.
> > But they share the same coordinate system of the ocean.
>
> There seems to be a bit of "doublethink" creeping in here. The two ships
> are occupying the same inertial frame and in two inertial frames at the same
> time. So, can we measure their relative speeds, or not? Or can we simply
> not measure the speed of an object on one ship relative to the speed on the
> other ship?
Yes All the velocities can, and must, be measured relative to one
another.
Since each ship is moving with respect to the other, it defines it's own
inertial system. Both are contained in the inertial system of the ocean,
and both contain other inertial systems of the people and rats moving
about them.
The constant velocity movement of any body is only relative to another
body.
Otherwise you would have no way of knowing that you are moving. If I
blindfold you, or lock you in a big can, there is no "meter" that can
tell you that you are moving at a fixed velocity.
You have to look out the window, so to speak, to determine that you are
moving by observing your motion relative to another body. But you can
not determine if it is you or the other body that is moving. Motion at
constant velocity is only w.r.t. another reference system.
> These questions may seem ignorant, because the answers are obvious. But, if
> we accept that these mesurements are possible, then the big question comes
> back - at what point does it become impossible to make such comparisoms? We
> either have to say that at a certain relative speed, the time frames make
> measurements impossible, or we say that things drift apart. Neither option
> can make any sense. I cannot define the boundary conditions between one
> situation and the other.
You're on the bow of another ship and I, from my bow, flash a beam of
monochromatic (single color) light at you If you are moving at the same
speed as me (ie, we are not moving relative to each other) then you
will see the same color as I flashed you.
SUppose I flash you the lightbeam color information in morse code
(bright blue, 600nm wavelength) and you measure the wavelength, and
determing it is 600nm. Then you know I am not moving relative to you.
You confirm this by looking at my bow and see that it is in a fixed
position, relative to your bow. Then you say we are not moving, relative
to each other.
A remote star sends out a beam of light also, and since it comes from a
Hydrogen atom, it's wavelength is well known. But when I observe it, the
color is a little bit different, somewhat more red that I would expect
it to be.
I can deduce from this that the star is moving away from me. Since the
stars are too far away to observe their movement, unlike the bow of the
ships, this is how we determine stellar motion relative to our own
motion.
>
> >
> >
> > A mu meson has a lifetime of about a microsecond.
> >
> > It takes about 10 microseconds for one to reach the ground from where
> > they originate in the high atmosphere.
>
> > Yet most mu mesons make it to the ground.
> >
> > Why? Because the stopwatch that we have on the ground says 10
> > microseconds, but because they are moving at close to lightspeed, the mu
> > mesons only think about a half microsecond has passed. So most hit the
> > ground.
> >
> It is also possible, (because we cannot measure anything beyond the speed of
> light) that we *assume* that the muon is travelling at less than the speed
> of light. AFAIK, the only evidence that they survive for 10, (or 50) uS, is
> that that length of time would be required for that distance to be covered
> at a speed approaching the speed of light. What would happen if the muon
> were travelling at 5 (or 25) times the speed of light?
> If we remove the obstacle, (which we created,) that says that nothing can
> travel at greater than the speed of light, then we can make sense of the
> universe using newtonian physics.
>
> > It isn't a "manner of speaking" or a "physicist's trick of accounting"
> > that causes time to appear to pass differently to different observers
> > moving wrt each other.
> >
> > It seems to be a real effect, a property of the universe that we live
> > in.
>
> Most of which can also be explained by lifting the "false" ceiling - the
> speed of light.
If the light had a different speed for different observers (lifting the
ceiling, as you say) then it would not have the wavelenght shift that it
does seem to exhibit.
The constance of the lightspeed has to be accounted for by the concept
of the conservation of energy. This is a priinciple that we have
observed to be at work in the universe.
But just because we observe and can interpret this principle does not,
of course, explain either it's cause or somehow predict that it, the
PRINCIPLE, should even exist.
Basically all our physical principles are "educated guesswork". But by
their judicious usage we can make outstanding predictions that would
bedazzel someone that did not use them.
We may have the wrong explanation for the way light and space-time
works, and it's only partially described at best anyway, but a better
theory would have to produce a model that can answer all the existing
problems plus produce answers to a few new ones that we haven't yet
recognized.
>
> <snip>
> > > Do not think that these
> > > theories are right because some scientists said so.
> >
> > Of course not. But if you need to make a prediction of where the rocket
> > will land you have to use an appropiate physical model. Do you want to
> > account for the difference in the pulses of a cesium clock taken up 100
> > feet in a tower, then you can't say it's because you forgot to wind it.
> > :) OK you can say that but you won't be relied upon after saying you
> > lost the wind-up key. :) Einstein says it's different because the
> > gravitational field 100 feet up has less effect on slowing it down than
> > the same clock on the ground. Time passes slower in a stronger
> > gravatational field.
>
> Perhaps caesium is simply affected by gravity and/or forces of acceleration?
> Certainly, any observable physical oscillations of objects with mass are
> affected by gravity and acceleration. Why should the innard of a caesium
> atom be any different?
Maybe. But gravitational acceleration is only in one direction so it
would matter in which direction I held the clock, wouldn't it?
IOW, you can't turn a pendulum on it's side and expect the same result,
right? So naturally you conclude, rightly so, that a pendulum behaves a
certain way in a gravitational field. The atomic clock behaves in a very
different way.
> <snip>
> > Consider a star who's position is well known and at this moment is
> > behind the sun.
> >
> > But (during the darkness of an eclipse) that star is clearly visable and
> > not obscured by ol' sol. Because the light ray from the star was bent
> > toward the sun as it went past it and then ended up in our eye. A bit if
> > a curve as it went by the sun.
> >
> > Astronomers see objects behind other large objects because the light is
> > bent back towards our view.
> >
> I don't see any problem with this at all. Chuck anything past the sun and
> its path will be deflected. Why try to make it complicated? I can see that
> the path of light will bend as it goes past a large gravitational source,
> without bending time and space. Light simply needs to have certain
> properties of mass.
You now have a choice: Either the light is bent or the light travels in
a straight line and the space is bent.
>
> >> The reason that nobody has
> > > convinced me otherwise is not that I am too thick, it is because they
> are
> > > wrong.
> >
> > OK, but now you're starting to sound a bit like Jaxby. Remember, he
> > graduated from the eighth grade. :)
>
> I may not have Jaxby's IQ, but I have read, and tried to understand, your
> post. So to judge me relative to Jaxby is not valid, as I think that we
> must exist in different inertial frames.
Ok, I was just adding a small joke, it was not ment as an insult, and I
can see that it did not add the humor I intended it to add. Sorry. This
has been a dignified discussion and they are all too rare on the 'net, I
hope I have not spoiled that.
>
> BTW. Thanks for taking the time to write the post. I did learn something
> while reading it, even if I have not moved much from my position.
Welcome. :)
da
>
> Regards
>
> Donal
> --
Donal
Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0E23...@Armory.arm...
> Donal wrote:
> >
> > Dr ArmŽ <Ar...@Armory.arm> wrote in message
news:3A0CD7...@Armory.arm...
<snip>
> Otherwise you would have no way of knowing that you are moving. If I
> blindfold you, or lock you in a big can, there is no "meter" that can
> tell you that you are moving at a fixed velocity.
> You have to look out the window, so to speak, to determine that you are
> moving by observing your motion relative to another body. But you can
> not determine if it is you or the other body that is moving. Motion at
> constant velocity is only w.r.t. another reference system.
>
>
>
>
<snip>
> A remote star sends out a beam of light also, and since it comes from a
> Hydrogen atom, it's wavelength is well known. But when I observe it, the
> color is a little bit different, somewhat more red that I would expect
> it to be.
>
> I can deduce from this that the star is moving away from me. Since the
> stars are too far away to observe their movement, unlike the bow of the
> ships, this is how we determine stellar motion relative to our own
> motion.
I am happy with Doppler shift, just not happy with Doppler shift without
change in speed. See my "pebble in pond" below.
<snip>
> If the light had a different speed for different observers (lifting the
> ceiling, as you say) then it would not have the wavelenght shift that it
> does seem to exhibit.
I read this as saying that you could only have either a speed or a
wavelength shift.
I don't understand this. Consider a pond into which a pebble is dropped.
We take two measurements, one from a stationary (relative to the point where
the pebble hit the water)point, and one from a point that is moving towards
the impact point.
If you measure the passing speed of the first wave, and its wavelength, from
both positions you will get two answers. One will give *both* higher
frequency and speed than the other.
If it could be proved that the light from receding stars was coming towards
us at the speed of light then I would have to rethink my position. I don't
think that anybody has done this yet.
>
> The constance of the lightspeed has to be accounted for by the concept
> of the conservation of energy. This is a priinciple that we have
> observed to be at work in the universe.
>
> But just because we observe and can interpret this principle does not,
> of course, explain either it's cause or somehow predict that it, the
> PRINCIPLE, should even exist.
>
> Basically all our physical principles are "educated guesswork". But by
> their judicious usage we can make outstanding predictions that would
> bedazzel someone that did not use them.
>
> We may have the wrong explanation for the way light and space-time
> works, and it's only partially described at best anyway, but a better
> theory would have to produce a model that can answer all the existing
> problems plus produce answers to a few new ones that we haven't yet
> recognized.
>
When that happens, even cynics like me will be convinced.
As I see it, we keep coming up with a theory that predicts our *current*
observations. Then we make further observations which are at variance with
our predictive model. Instead of admitting that our model was wrong, we
_refine_ the model. Exactly the same process has been going on with
particle physics for the last 100 or so years. Not so long ago, the
electron was the smallest particle that could exist. There was also a
proton and a neutron. Further observation meant that this theory was wrong.
But they did not go back to square one and re-evualate their theories. They
simply added to their existing *knowledge*. This has continued to the
present day with a plethora of particles that have all been invented to try
to make observations fit.
>>Why should the innard of a caesium
> > atom be any different?
>
> Maybe. But gravitational acceleration is only in one direction so it
> would matter in which direction I held the clock, wouldn't it?
I don't think that affects things much. Acceleration forces will always act
in the same direction WRT to the the direction of deflection. Our
observance of time changes are all WRT to things approaching or going away
from us. Thus the acceleration forces will always be be the same relative
to us, and our measurements.
>
> IOW, you can't turn a pendulum on it's side and expect the same result,
> right? So naturally you conclude, rightly so, that a pendulum behaves a
> certain way in a gravitational field. The atomic clock behaves in a very
> different way.
>
My understanding is that the atomic clock depends on oscillation within the
atoms of the atomic clock. Why should forces of accelleration not affect
this oscillation. The atoms, and their constituent particles, have mass.
<snip>
> You now have a choice: Either the light is bent or the light travels in
> a straight line and the space is bent.
>
> > >
> > > OK, but now you're starting to sound a bit like Jaxby. Remember, he
> > > graduated from the eighth grade. :)
> >
>
> > I may not have Jaxby's IQ, but I have read, and tried to understand,
your
> > post. So to judge me relative to Jaxby is not valid, as I think that we
> > must exist in different inertial frames.
>
>
> Ok, I was just adding a small joke, it was not ment as an insult, and I
> can see that it did not add the humor I intended it to add. Sorry. This
> has been a dignified discussion and they are all too rare on the 'net, I
> hope I have not spoiled that.
Not for a second. I hoped that my "inertial frames" comment would give away
my appreciation of the wit. I should have used a term that I understood
properly.
Regards
Donal
--
The_navigator
Gilligan <gilligan...@my-deja.com> wrote:
How then can you explain the distortion in Mercury's and other
planets orbits and (thank goodness for the link to sailing) the
fact that GPS time signals have to be corrected...?
>
> I understand this. I also understand that the photons "clock" is the
> field of the photon extending into the space surrounding it. The field
> also carries the energy of the photon. When the photon has energy
added
> to it or subtracted it will change its frequency accordingly. The
> photon is reacting to external conditions.
Now how do you add energy to a photon exactly?
>
> I agree. Group velocity is sheninagans. This was also known for
> decades.
At elast we agree on soemthing! :)
> Fizeau showed that water speed was added to the light speed.
Really? Can you provide areference. Again, I though that Fizeau showed
that light speed was INVARIENT.
> Now here's the crux: Your methods are fine and will yield good results
> when applied correctly. However you are missing the most fundamental
> aspect. It is the definition, nature and measurement of time. First
> and
> utmost, time is an abstraction.
I agree. In Euclidian spance it is indistinguisable from distance.
> Time is the sequence of events when
> they occur. Time is a universal and a primitive, fundamental concept.
No, it is a dimension as re the other three we live in. Do you believe
in antimatter? Why then do you not think time can go backwards even if
as 4 dimensional beings we cannot see time going backwards?
> All this space/time distortion is an attempt to account for the
> transmittance or the measurement of a material representation of time.
> It is not the abstraction of time. If one holds time as an absolute
> measurement (yet realizing that the measurement of time by instruments
> is affected by the environment) one can conclude that velocity and
> lengths change.
> This logic of the distortion of time is erroneous. If I go to France
> and cut the standard meter in half, will everyone's shoe sizes double?
Yes! Everone will buy size 20 shoes instead of size 10. That is the
point, it is the perception which varies not the actuality. That is why
I say that it may 'seem' as if light can 'bend' but it does not.
> Will all of our feet have grown?
But it will 'seem' as if they had. Even Gilligrovel will say his feet
are two feet long...
Of course not. But then - can I
> conclude by cutting the meter in half that I caused everyone's
> speedometer to double in speed? No, So then I must conclude that by
> cutting the meter in half I caused everyone's clocks to slow down
> because the speedometers read faster for the same events. Yes this is
> silly, but so is the bending of time and space.
> Time is a universal, it does not conceptually change (it is a sequence
> of events).
But all the eveidence points to time being variable!
> On a contemplative note, if the big bang really did happen and the
> universe is flying apart at speeds greater than my Bucaneer can
> achieve, and the amount of matter is fixed - then one concludes the
> universe is becoming less dense. As it becomes less dense the speed of
> light must be slowing down.
No, the local time is getting slightly faster.
The_navigator
suddenly become 'inaccurate' if taken up an elevator or moved in a
plane? Why does the GPS system REQUIRE correction for relativistinc
effects between the satellites? Why is the elliptical orbit of Mercury
precessing?
All the ideas about Euclidean space-time are due to theories which are
mathematical equations. These theories (so far) are very good at
explaing most of what is known about matter and energy. That is why they
are 'acceptable'.
What would it take before you belive that time is not constant? Do you
believe that your GPS tells you where you are and does so because the
GPS system includes a correction for satellite clock time
distortion??????
I do not wish to argue this to death. It is your choice to believe or
not, just as it is your choice to believe in divine intervention to
explain the problems I gave you (above).
> Time IS constant. Space does NOT bend. The reason that nobody has
> convinced me otherwise is not that I am too thick, it is because they
> are wrong.
Maybe, but do you know what the uncertainty principle is?
Cheers MC
The_navigator
Gilligan <gilligan...@my-deja.com> wrote:
> Marty:
> I am not refuting GTR. For the most part I do not refute SRT (depends
> on whose version of it), I only apply it correctly and attempt to
> understand it by real physical explanation. As you can see Einstein
and
> I are agreement on the nature of the velocity of light, what affects
it
> and the consequences in SRT.
Gilligan, Einstein did not say that light speed was not constant. he
said that there was nothing in SRT to *require* universal constancy of
light speed. But c as a constant has stood up a lot longer than
Eistein's cosmological constant!! (Hahahaha) Do you not see (or know
about) the political nature of Einstein the man and see why he said
things the way he did ??? Remember that Einstein said 'God does not play
dice'. But you know from you experience that he does -doesn't he?
Donal
The_navigator <the_na...@my-deja.com> wrote in message
news:8un7gs$irr$1...@nnrp1.deja.com...
Yes, I am uncertain, but what about the disciples of Relativity? Actually,
that bit above is more of a challenge than a God given fact. It is born of
a frustration due to the "we are more clever, and Einstein was a genius"
method of argueing the point. I have not yet met anyone who believed in the
principles of relativity, and who could explain them. At some point in
their arguement they always have to fall back on the evidence of a third
party.
If we believed that time and space are constant, then we would seek other
explainations for the observed phenomena. The bending of light round the
sun was one prediction that was verified by observation. It nearly
convinced me, until I stopped and realised that _my_ theories would also
predict the bending of light round the sun. Light has certain properties of
mass, and will therefore be affected by gravity.
Perhaps if we examine the effects of acceleration on time keeping
mechanisms, most of which are based on some form of oscillation, we might be
rewarded. A GPS satellite undergoes constant acceleration as the earth's
gravity changes its course.
I agree with you that we cannot argue this to death, and I admit that in
these discussions that I am out of my depth. However, that does not mean
that I will ever accept something that I do not understand, simply because
someone who is more clever than I said so. (Except for advice on trimming
the jenny, of course.)
One thought. Would it be possible to re-define the theories so that time
was a constant and some other "variable" had to be modified instead?
Regards
Donal
--
The_navigator
"Donal" <do...@lanode.com> wrote:
<some snipped>
>
> If we believed that time and space are constant, then we would seek
other
> explainations for the observed phenomena. The bending of light round
the
> sun was one prediction that was verified by observation. It nearly
> convinced me, until I stopped and realised that _my_ theories would
also
> predict the bending of light round the sun. Light has certain
properties of
> mass, and will therefore be affected by gravity.
But Donal, why do you say -this it is easy to show that the photon has
no rest mass and only momentum...
>
> Perhaps if we examine the effects of acceleration on time keeping
> mechanisms, most of which are based on some form of oscillation, we
might be
> rewarded. A GPS satellite undergoes constant acceleration as the
earth's
> gravity changes its course.
>
Well yes, but we tend to prefer theories that explain as much as
possible in a coherent manner. I cannot answer your conjecture because I
do not fully see its basis, but tell me why do you think the period of
vibration depends on acceleration in such a way that when the clock is
first taken up a building and then down again that the initial speed up
is not compltely reversed by the 180 degree reversal(s) in the direction
of acceleration both at the top and at the bottom????
>
> One thought. Would it be possible to re-define the theories so that
time
> was a constant and some other "variable" had to be modified instead?
Well now, I can't say that. In Euclidian models I believe that the
dimensions of time and space are completely interchangeable. Of course a
higher dimensional model could have an extra function to take care of it
all. But since we could not directly measure the parameters of the extra
dimensions we might as well say 'God' did it...
Dr Arm®
> > to it or subtracted it will change its frequency accordingly. The
> > photon is reacting to external conditions.
>
> Now how do you add energy to a photon exactly?
Two ways that I can think of.
1. By moving the emitter source. The velocity of light doesn't change
but it's frequrency does, hense it's energy changes. E = h v, v the
frequency, which changes with wavelength.
THis would also include moving the receiver to change the photon's
energy.
2. The Gravitational redshift. By leaving a gravitational mass, light
experiences a red shift indicating a loss of energy to the gravitational
field. eg: Light leaves a star and as it moves further away from the
star it's wavelength increases.
Other than that I can't think offhand of another process. Generally a
photon is absorbed and re emitted with different energy, as in lasing,
but that isn't what you asked, I think.
>
> >
> > I agree. Group velocity is sheninagans. This was also known for
> > decades.
>
> At elast we agree on soemthing! :)
Disagree. Group velocity is very meaningful and useful. Where did this
statement come from? I tried to trace it back in your posts but it seems
to have come out of confusion. <g>
It's phase velocity that is not especially useful.
da
Dr Arm®
>
> Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A0E23...@Armory.arm...
> > Donal wrote:
> > >
> > > Dr ArmŽ <Ar...@Armory.arm> wrote in message
> news:3A0CD7...@Armory.arm...
> <snip>
>
> > Otherwise you would have no way of knowing that you are moving. If I
> > blindfold you, or lock you in a big can, there is no "meter" that can
> > tell you that you are moving at a fixed velocity.
> > You have to look out the window, so to speak, to determine that you are
> > moving by observing your motion relative to another body. But you can
> > not determine if it is you or the other body that is moving. Motion at
> > constant velocity is only w.r.t. another reference system.
> >
> >
> >
> >
> <snip>
> > A remote star sends out a beam of light also, and since it comes from a
> > Hydrogen atom, it's wavelength is well known. But when I observe it, the
> > color is a little bit different, somewhat more red that I would expect
> > it to be.
> >
> > I can deduce from this that the star is moving away from me. Since the
> > stars are too far away to observe their movement, unlike the bow of the
> > ships, this is how we determine stellar motion relative to our own
> > motion.
>
> I am happy with Doppler shift, just not happy with Doppler shift without
> change in speed. See my "pebble in pond" below.
I was afraid you would say that! There's a difference: The doppler shift
of sound waves is not the same as the doppler shift of EM
(electromagnetic) waves.
EM waves propagate through the "vacuum" of space, acoustic waves require
a medium to exist in, including your pebble's acoustic waves.
>
> <snip>
> > If the light had a different speed for different observers (lifting the
> > ceiling, as you say) then it would not have the wavelenght shift that it
> > does seem to exhibit.
>
> I read this as saying that you could only have either a speed or a
> wavelength shift.
Yes, Going back a few posts, it's the constancy of lightspeed that gives
rise to the effect of time dialation, and in this case wavelength shift.
> I don't understand this. Consider a pond into which a pebble is dropped.
> We take two measurements, one from a stationary (relative to the point where
> the pebble hit the water)point, and one from a point that is moving towards
> the impact point.
> If you measure the passing speed of the first wave, and its wavelength, from
> both positions you will get two answers. One will give *both* higher
> frequency and speed than the other.
> If it could be proved that the light from receding stars was coming towards
> us at the speed of light then I would have to rethink my position. I don't
> think that anybody has done this yet.
You are thinking clearer than I am at this point, and you have made an
excellent point, tha reminds me of an expoeriment. While I can't point
you to a reference, I can tell you how to do that experiment.
It is the same as an experiment that was done to determine lightspeed a
hundred years ago. Take two toothed wheels, one on each end of a shaft.
Allow the beam to folow a path along the direction of the axel and in
the space between two teeth on the first wheel, and again two teeth on
the second wheel.
Now spin the wheel. You will get light through the second wheel when
the tooth on the second wheel has moved out of the way of the burst of
light that was admitted bewtween the first wheels teeth. If you know the
RMP of the wheel and the distance from first wheel to secnd, you can
calculate the speed of light.
Now that I type this out I seem to remember someone actually doing this
on starlight.
If you go to the equator, you are moving at about 900 miles per hour
toward the sun in the morning and away from the sun in the evening. Yet
there is no measurable difference in lightspeed given the 1800 mph
difference inthe speed of the observer. Radar on a the SR70, or even the
LEM while it was on the way to the moon traveled at the same lightspeed
even thought the velocity of the craft was very high.
An interferometer experiment has been done with the direction of the
beam of light in the same direction of motion as the earth's spin (that
900 mph again). Then turn the apartus 90 degrees, so these is no avial
motion, and the speed is the same.
This same experiment has been performed in the direction of earth's
spin, the direction of the solar system's drift in space, the milky
way's spin, etc, etc, etc and no observable difference in the lightspeed
has been measured, even though these velocities are very high (I forgot
what the velociity do to the solar system drifting through space is,
maybe 24,000 mph, but I don't remember. Very large!).
So there is experimental basis for the constancy of lightspeed. I should
have thought about some of this earlier.
You are of course free to create your own model of the universe, as you
say yours might allow for the gravitational bending of light, somehow.
But Newton's laws did not allow that to happen and they could not have
predicted it. So certainly there is no way to quantify the effect.
Einstien does and gives us a way to quantitatively solve and predict
that effect now. If we someday recognize another set of laws that does
allow for the gravitational bending of light but does not recognizre the
constancey of lightspeed then I will be forerced to give your theory
another look. <g>
>
> >
> > The constance of the lightspeed has to be accounted for by the concept
> > of the conservation of energy. This is a priinciple that we have
> > observed to be at work in the universe.
> >
> > But just because we observe and can interpret this principle does not,
> > of course, explain either it's cause or somehow predict that it, the
> > PRINCIPLE, should even exist.
> >
> > Basically all our physical principles are "educated guesswork". But by
> > their judicious usage we can make outstanding predictions that would
> > bedazzel someone that did not use them.
> >
> > We may have the wrong explanation for the way light and space-time
> > works, and it's only partially described at best anyway, but a better
> > theory would have to produce a model that can answer all the existing
> > problems plus produce answers to a few new ones that we haven't yet
> > recognized.
> >
>
> When that happens, even cynics like me will be convinced.
The one thing i can predict is that a new theory will be even more
bizare.
I'm not sure we're ready for a grand unifying theory yet, based on the
research we have done, That new theory will include gravity as well as
electromagnet effects. Something that unites the four forces from one
primordial pre-force.
Perhaps the string theory is the right one, but nodody up till now has
been able to solve the equations of string theory. In any case as far as
we know, they both still support the constancy of lightspeed. No
exception has been found to that, and believe me, we have looked.
>
> As I see it, we keep coming up with a theory that predicts our *current*
> observations.
Yes, of course. How else? No saccasism inteneded,
Physical theories have been very little developed by "prediction" and
are mostly developed to answer existing problems that the existing
theory doesn't solve. THat's how lightspeed constancy came abot in the
first place.
Keplers' planetary laws described what previouslyt had been observed but
not derscroibable.
Newton devised the laws of motion to ecxplain how the observed moving
bodies behaved, he did not predict that they woulfd behave that way!
Einstien and Lorentz understoofd that the was someting wrong with
newtonian motion when it canme to high velocities and so puostulated the
consrtancyt of lightspeed. The above experiments seem to bear that out.
The effect of time dialation is not mearly an effect on clocks. It is
not a "trick" or something that happens to just the mechanical-ness of
the clocks in the experiment. It happens to YOU also. A person moving
ages slower than the observer that watched him, irregardless of the
direction in which he moved.
The Milky Way galaxy is 100 light years across in diameter.
A man gets into a rocket and leaves this side of the Milky Way heading
for the other side.
He traveles at .9997 the speed of light, w.r.t. you, to me, to the rest
of the galaxy.
When he reaches the other end of the Milky Way and lands at his new
home, he will be about forty years older then when he left.
For you and me and the entire Milky Way, about 100,000 years will have
passeed since he left Earth.
If he was twenty when he left, he will arrive in time for his sixtieth
birthday, just in time for Social Security.
But if he expects the Social Security check to come from earth, they
will take that same 100,000 years that *we* observed it took him to get
where he is. Of course the SSA would have made this same calculation to
know his true age.
Unless Earth started sending the checks forty years after his departure,
while he himself was still much younger, he will probably not live to
recveive the first check. In any case, it will be two hundred thousand
years before you get the first canceled check back.
Neat stuff, huh?
>
> <snip>
> > You now have a choice: Either the light is bent or the light travels in
> > a straight line and the space is bent.
> >
> > > >
> > > > OK, but now you're starting to sound a bit like Jaxby. Remember, he
> > > > graduated from the eighth grade. :)
> > >
> >
> > > I may not have Jaxby's IQ, but I have read, and tried to understand,
> your
> > > post. So to judge me relative to Jaxby is not valid, as I think that we
> > > must exist in different inertial frames.
> >
> >
> > Ok, I was just adding a small joke, it was not ment as an insult, and I
> > can see that it did not add the humor I intended it to add. Sorry. This
> > has been a dignified discussion and they are all too rare on the 'net, I
> > hope I have not spoiled that.
>
> Not for a second. I hoped that my "inertial frames" comment would give away
> my appreciation of the wit. I should have used a term that I understood
> properly.
It was fine, thanks. :)
da
>
> Regards
>
> Donal
> --
The_navigator
question which was, How do you add energy to a photon (once it has been
emitted). Addition in parenthesis for you. If you want to join this
thread, can you explain why the photon energy is different when emerging
from a gravitational well (remember the photon has no mass...)
Cheers MC
Dr Arm®
>
> da, yes yes, we are all aware of that, you missed the point of the
> question which was, How do you add energy to a photon (once it has been
> emitted). Addition in parenthesis for you. If you want to join this
Thank you. My conversation with Donal was going w sowwell it was taking
all my attention., IU was only peeping into your thread.
> thread, can you explain why the photon energy is different when emerging
> from a gravitational well (remember the photon has no mass...)
A photon has no REST mass. We attribute the quality of mass to a photon,
that's what allows it to have momentum p (= mu = hv/c, where u = c for a
photon).
so m = p/c = hv/c**2 is the effective mass of a (not-at-rest) photon.
Now the the gravitational potential energy is the acceleration due to
it's gravity G of the star and the distance and the mass
mGd = potential energy, is the loss of energy as the photon reaches a
distance d from the star
hv/c**2 G d + hv = h v0 (the original energy when the photon left the
star).
The shift in frequency is v - v0.
This accounts for the so-called gravitational red shift. This works
either way. As the photon approaches a larger mass, it gains energy from
the gravitational mass and obtains a positive delta v, or a blue shift.
da
The_navigator
delta v is the change in frequency not velocity of the photon. That is
because the photon only travels at the speed of light and so can only
change energy by changing frequency. And for the sceptics, this has been
directly measured in experiments on Earth!
Thanks da.
Next, it's all explained by conservation of energy but how does the
photon 'feel' the gravitational field? Could it be that Chiquita
Banana is not yellow but some other colour and all we are seeing is a
redshift from her high speeds? Is the Lorentz contraction at this speed
the explanation of her dumpy lines? Or do we risk a severe repremand
the Putzmaster Crapton for asking this question?
Cheers MC
In article <3A0F7E...@Armory.arm>,
Dr Arm®
>
> I hope Gilligrovel reads this. Please note (it's important) that the
> delta v is the change in frequency not velocity of the photon.
Of course. I used u for velocity.
BTW, I did have to check on the momentum of the photon (hv/c) but I did
remember everything else, including the gravitational red shift
solution. I recall most textbooks solve it from the point of view of the
final observer, but I remember it from the point of view of the photon,
much like Einstein did.
That is
> because the photon only travels at the speed of light and so can only
> change energy by changing frequency. And for the sceptics, this has been
> directly measured in experiments on Earth!
Yes, Seem other post to Donal, I recalled a few of them..
>
> Thanks da.
A pleasure actually.
>
> Next, it's all explained by conservation of energy but how does the
> photon 'feel' the gravitational field?
Yes, all very conventional, Newtonian gravitational potentials and
quantum photon effects. To solve for the black hole radius (where v goes
to zero) the same problem requires a relativistic calculation.
Could it be that Chiquita
> Banana is not yellow but some other colour and all we are seeing is a
> redshift from her high speeds?
Naw. You would have to get the thing up to a decent speed in order to
see the color shift, something I've read the banna barge is incapable
of. But if we launched the thing as a fast moving ballistic projectile,
perhaps with the use of a catapult, there's no telling how many
interesting principles we could deduce.
Is the Lorentz contraction at this speed
> the explanation of her dumpy lines? Or do we risk a severe repremand
> the Putzmaster Crapton for asking this question?
"God does not play dice with Putzes", Einstein, I think. <g>
da
>
> Cheers MC
>
> In article <3A0F7E...@Armory.arm>,
> Dr...@mailroom.com wrote:
Marty
The_navigator <the_na...@my-deja.com> wrote:
> Dear Marty
>
> As I understand it, radar guns do not measure Doppler shift (this is
> probably too small to measure with simple equipment). They work by
> measuring the time of flight of a radar pulse (which assumes a
constant
> c -GILLIGAN please note that next time you get a ticket!!!). The
> differential of this signal wrt time is 'speed'.
>
>
Dear MC:
Having returned to work and having my library at my disposal again, I
find that police radars do indeed measure doppler shift.
They do this by mixing (beating or hetrodyning) the the recieved
wavetrain with an image of the transmittted train, after a bit of
filtering this yields a beat frequency which is directly proportional to
the difference between the transmitted frequency and the recieved
frequency, ie., the Doppler shift! Simplicity itself!
Cheers
Marty
PS. thanks to Gilly and DA for other defences.
The_navigator
Of course being and expert in relativity I could point out that the
Doppler shift is nothing more than a time distortion problem within the
frame of reference of the radar wave :) and in fact it is simply a
change in the time of flight :))) But I won't 'cos even for me that
would be stretching it a bit. No, I can see that my intended defense
against speeding tickets would be naught (I was thinking about multiple
refelections of pulses) and that the machine measures the beat frequency
of the mixed waves. :( I wonder how it measures frequency -phase locked
loop or digitally? Of course if one then could modulate the reflected
wave at the right rate then maybe you could defeat the system? :)
This is, of course not off topic, as I am trying to explain how Crapton
could ever think he could sail faster than me on a windsurfer...
:)
Cheers MC
In article <8urro4$9en$1...@nnrp1.deja.com>,
Donal
nights, and this is a subject that is difficult enough when sober.
Dr Arm® <Ar...@Armory.arm> wrote in message news:3A0F61...@Armory.arm...
> Donal wrote:
> >
> >
> > I am happy with Doppler shift, just not happy with Doppler shift without
> > change in speed. See my "pebble in pond" below.
>
>
> I was afraid you would say that! There's a difference: The doppler shift
> of sound waves is not the same as the doppler shift of EM
> (electromagnetic) waves.
>
> EM waves propagate through the "vacuum" of space, acoustic waves require
> a medium to exist in, including your pebble's acoustic waves.
Why should a vacuum affect the fundamental properties of a wave pattern?
Hmmm, now that I have asked it, it might be more sensible to ask "How can a
wave exist outside the influence of gravity?" . Perhaps we do not have any
understanding of light at all??? This is genuine 'thinking out loud', but
is it possible that light is neither wave or mass? Is it possible that we
have been barking up the completely wrong tree for the last couple of
centuries?
> > <snip>
> > > If the light had a different speed for different observers (lifting
the
> > > ceiling, as you say) then it would not have the wavelenght shift that
it
> > > does seem to exhibit.
> >
> > I read this as saying that you could only have either a speed or a
> > wavelength shift.
>
> Yes, Going back a few posts, it's the constancy of lightspeed that gives
> rise to the effect of time dialation, and in this case wavelength shift.
<snip>
>
> It is the same as an experiment that was done to determine lightspeed a
> hundred years ago. Take two toothed wheels, one on each end of a shaft.
>
> Allow the beam to folow a path along the direction of the axel and in
> the space between two teeth on the first wheel, and again two teeth on
> the second wheel.
>
> Now spin the wheel. You will get light through the second wheel when
> the tooth on the second wheel has moved out of the way of the burst of
> light that was admitted bewtween the first wheels teeth. If you know the
> RMP of the wheel and the distance from first wheel to secnd, you can
> calculate the speed of light.
>
> Now that I type this out I seem to remember someone actually doing this
> on starlight.
>
> If you go to the equator, you are moving at about 900 miles per hour
> toward the sun in the morning and away from the sun in the evening. Yet
> there is no measurable difference in lightspeed given the 1800 mph
> difference inthe speed of the observer. Radar on a the SR70, or even the
> LEM while it was on the way to the moon traveled at the same lightspeed
> even thought the velocity of the craft was very high.
>
> An interferometer experiment has been done with the direction of the
> beam of light in the same direction of motion as the earth's spin (that
> 900 mph again). Then turn the apartus 90 degrees, so these is no avial
> motion, and the speed is the same.
This is a reference to the famous (Mickleson?? and a.n. other ) experiment
that Einstein used as the foundation of his work.
The detectors and emitters were in the same room. The results also back up
my theory. They failed to detect a difference in the speed of light, which
had travelled two different paths around the same room, but had travelled
the same distance. If the speed of the light was relative to the speed of
the emitter, the result would have been the same, or, to put it another way,
exactly what I would have proposed. This is a prime example of "scientists
looking for evidence to back up their theories".
>
> This same experiment has been performed in the direction of earth's
> spin, the direction of the solar system's drift in space, the milky
> way's spin, etc, etc, etc and no observable difference in the lightspeed
> has been measured, even though these velocities are very high (I forgot
> what the velociity do to the solar system drifting through space is,
> maybe 24,000 mph, but I don't remember. Very large!).
>
> So there is experimental basis for the constancy of lightspeed. I should
> have thought about some of this earlier.
>
>
> You are of course free to create your own model of the universe, as you
> say yours might allow for the gravitational bending of light, somehow.
> But Newton's laws did not allow that to happen and they could not have
> predicted it. So certainly there is no way to quantify the effect.
> Einstien does and gives us a way to quantitatively solve and predict
> that effect now. If we someday recognize another set of laws that does
> allow for the gravitational bending of light but does not recognizre the
> constancey of lightspeed then I will be forerced to give your theory
> another look. <g>
>
>
> >
> > >
>
<snip>
> >
> > When that happens, even cynics like me will be convinced.
>
>
> The one thing i can predict is that a new theory will be even more
> bizare.
> I'm not sure we're ready for a grand unifying theory yet, based on the
> research we have done, That new theory will include gravity as well as
> electromagnet effects. Something that unites the four forces from one
> primordial pre-force.
>
> Perhaps the string theory is the right one, but nodody up till now has
> been able to solve the equations of string theory. In any case as far as
> we know, they both still support the constancy of lightspeed. No
> exception has been found to that, and believe me, we have looked.
Pah, no scientist looks for evidence that disproves his theories.
A few years ago I visited a nuclear fusion energy generation research
project. The guide proudly boasted that they had got 200MW out of their
taurus. I simply asked the unthinkable question........ go on guess
...........
How much did you put in? The rather embarrased answer was "ummm errr
hahem 250". I suggested that a dustpan and brush be immediately applied
because they had obviously converted energy to mass!! They didn't take my
suggestion up, because they had spent billions trying to do the opposite.
> >
> > As I see it, we keep coming up with a theory that predicts our
*current*
> > observations.
>
>
> Yes, of course. How else? No saccasism inteneded,
When they propose a theory that predicts observations that are as yet
unobserved, then I will take them a bit more seriously.
>
> Physical theories have been very little developed by "prediction" and
> are mostly developed to answer existing problems that the existing
> theory doesn't solve. THat's how lightspeed constancy came abot in the
> first place.
>
> Keplers' planetary laws described what previouslyt had been observed but
> not derscroibable.
>
> Newton devised the laws of motion to ecxplain how the observed moving
> bodies behaved, he did not predict that they woulfd behave that way!
>
> Einstien and Lorentz understoofd that the was someting wrong with
> newtonian motion when it canme to high velocities and so puostulated the
> consrtancyt of lightspeed. The above experiments seem to bear that out.
Maybe, if they had considered that the speed of light would affect their
observations, they would have come up with a different answer.
>
> The effect of time dialation is not mearly an effect on clocks. It is
> not a "trick" or something that happens to just the mechanical-ness of
> the clocks in the experiment. It happens to YOU also. A person moving
> ages slower than the observer that watched him, irregardless of the
> direction in which he moved.
Emmm, sorry, but how do you decide which person is moving relative to the
other? If one stands still on the earth's surface, and the other walks
contra to the earth's rotation, which of them ages more slowly? If one of
them raises himself a foot above the Earth's surface and then remains
stationary(relative to the centre of the Earth), does the chap who is
stationary on the surface age more rapidly, or more slowly, than the other?
This is the nub of the problem. For each of the observers, time is passing
more slowly for the other. Therefore time has become completely 'broken'.
It is passing faster and slower simultaneously for the same 'observer'.
This sounds incredibly complicated, so let's just take your(widely accepted)
statement "A person moving
ages slower than the observer that watched him, irregardless of the
direction in which he moved. "
Either person can consider himself stationary, and therefore the the other
must be ageing more slowly. As *either* person can be considered
stationary, *both* must be ageing more slowly than the other,
simultaneously. This is patently ridiculous.
Regards
Donal
--
Donal
The_navigator <the_na...@my-deja.com> wrote in message
news:8unhgg$qev$1...@nnrp1.deja.com...
> In article <974075699.7710.0...@news.demon.co.uk>,
> "Donal" <do...@lanode.com> wrote:
> <some snipped>
>
> >
> > If we believed that time and space are constant, then we would seek
> other
> > explainations for the observed phenomena. The bending of light round
> the
> > sun was one prediction that was verified by observation. It nearly
> > convinced me, until I stopped and realised that _my_ theories would
> also
> > predict the bending of light round the sun. Light has certain
> properties of
> > mass, and will therefore be affected by gravity.
>
> But Donal, why do you say -this it is easy to show that the photon has
> no rest mass and only momentum...
The photons coming from the hidden stars are not at rest. Momentum is a
function of mass.
> >
> > Perhaps if we examine the effects of acceleration on time keeping
> > mechanisms, most of which are based on some form of oscillation, we
> might be
> > rewarded. A GPS satellite undergoes constant acceleration as the
> earth's
> > gravity changes its course.
> >
>
> Well yes, but we tend to prefer theories that explain as much as
> possible in a coherent manner. I cannot answer your conjecture because I
> do not fully see its basis, but tell me why do you think the period of
> vibration depends on acceleration in such a way that when the clock is
> first taken up a building and then down again that the initial speed up
> is not compltely reversed by the 180 degree reversal(s) in the direction
> of acceleration both at the top and at the bottom????
Quite simply because acceleration is not dependant on direction.
Acceleration can be up or down, or even sideways.
>
>
> >
> > One thought. Would it be possible to re-define the theories so that
> time
> > was a constant and some other "variable" had to be modified instead?
>
> Well now, I can't say that. In Euclidian models I believe that the
> dimensions of time and space are completely interchangeable. Of course a
> higher dimensional model could have an extra function to take care of it
> all. But since we could not directly measure the parameters of the extra
> dimensions we might as well say 'God' did it...
>
We do not have to go that far. In any equation that you can solve, there
are variables which can only be balanced by known values. Thus, in any
equation where you think that *time* is a variable, you could make another
item 'variable' and thus time can become constant. For example, if you
assume that the speed of light is constant relative to the *emitter*, and
variable to the receptor, then the rest of the theory will work if you
question the ability of the observer to measure what he sees. Most of our
measuring equipment is based on electronics where the electrons also move at
the speed of light.
Regards
Donal
--
The_navigator
particle and induce a chnage in that particle the change should be
reversible if the direction of the acceleration is reversed. If this is
not the case then the particle must irreversibly change after
acceleration and then it is then hard to see how your model works. Note
that the time 'distortion' produced by flying a clock around is not
reversable but acceleration is. Hence a big flaw in your initial premise
I think. It is simple to accept SRT and consider time as one of the
dimensions of (4 dimensional) space-time. Now at this point you will say
Aha! but time cannot go backwards but we can move backwards. The answer
is yes that is correct but it is our inability to 'see' and 'interact'
with time that is a part of the problem. The second is that entropy must
increase with time. So to reverse time you must be able to decrease
entropy in the universe and this implies an even higher level (invisible
to us) interaction than is possible with the realm of space-time...
Hence we would not be able to observe the effect of this interaction and
so time reversal would not exist for us!
Cheers MC
In article <974250657.16104.3...@news.demon.co.uk>,
Dr Arm®
>
> Sorry that I have taken a couple of days to reply. Monday nights are club
> nights, and this is a subject that is difficult enough when sober.
>
> Dr Arm® <Ar...@Armory.arm> wrote in message news:3A0F61...@Armory.arm...
> > Donal wrote:
> > >
> > >
> > > I am happy with Doppler shift, just not happy with Doppler shift without
> > > change in speed. See my "pebble in pond" below.
> >
> >
> > I was afraid you would say that! There's a difference: The doppler shift
> > of sound waves is not the same as the doppler shift of EM
> > (electromagnetic) waves.
> >
> > EM waves propagate through the "vacuum" of space, acoustic waves require
> > a medium to exist in, including your pebble's acoustic waves.
>
> Why should a vacuum affect the fundamental properties of a wave pattern?
It doesn't really, only that the two different wave have two different
origins.
> Hmmm, now that I have asked it, it might be more sensible to ask "How can a
> wave exist outside the influence of gravity?"
Why not?
. Perhaps we do not have any
> understanding of light at all???
Maybe.
This is genuine 'thinking out loud', but
> is it possible that light is neither wave or mass?
Actually I think it usually is said the other way, that light is either
a particle or a wave.
I see your point, but I don't see that it can lead anywhere, unless you
know, or can postulate, what that "other thing" that isn't wave or mass
might be.
Usually we analyse light as thought it were a wave while in transit, and
a particle when it arrived.
Negative. Actually Michaleson never believed the results of his
experiment for a long time. He was a believer in the ether theory and
even though he published his results, he doubted them for several years.
Honest!
There was another attempt to reconcile euclidian geometery with the
observations of space time dialation. It was postulated that the ether
was causing the experimental apartus to expand and contract depending on
which direction it was pointed. But that theory never made much ground,
I don't know exactly why offhand.
We accept the sun as center of the solar system today as fact, but for
the longest time astronomers tried to reconcile the planatary movements
with spheres within spheres. It didn't hold up either.
That's not true. Most great discoveries have been made by an observant
scientist who saw something that he did not expect. I think it was the
Compton effect that was discovered because one out of every 8000
electrons wound up ina different trajectory than the existing theory
predicted. From that little discovery we have electron microscopes.
>
> A few years ago I visited a nuclear fusion energy generation research
> project. The guide proudly boasted that they had got 200MW out of their
> taurus. I simply asked the unthinkable question........ go on guess
> ...........
> How much did you put in? The rather embarrased answer was "ummm errr
> hahem 250". I suggested that a dustpan and brush be immediately applied
> because they had obviously converted energy to mass!! They didn't take my
> suggestion up, because they had spent billions trying to do the opposite.
Yeah, fine. so you met a technician masquerading as a scientist,
obviously not Newton or Einstein. Everybody has a job, he was aparently
just doing his, whatever that was. I don't think that describes the
demise of experimental physics. Even unsuccessfiul experiments have to
be performed. I'm not really sure that this illustrates anything except
as an arguement to end experimental physics research. I don't actually
know if that's a good idea, even if they never develope fusion reactors.
Like defense spending, some of it is a good thing, it generates other
technologies, and we are nothing if not a technological soceity. Hey if
the guy turned out to be a bank robber I also don't feel it would be
fair to characterize all physicists as bank robbers. Or even a lot of
them.
>
> > >
> > > As I see it, we keep coming up with a theory that predicts our
> *current*
> > > observations.
> >
> >
> > Yes, of course. How else? No saccasism inteneded,
>
> When they propose a theory that predicts observations that are as yet
> unobserved, then I will take them a bit more seriously.
We're going over the same ground again,
That's what relativity did that made it so well received. That's why I
brought up all those experiments, like the star behind the sun. You
already got your wish. Nothing else could ahve solved that problem,
before. It was a vindication of relativity.
>
> >
> > Physical theories have been very little developed by "prediction" and
> > are mostly developed to answer existing problems that the existing
> > theory doesn't solve. THat's how lightspeed constancy came abot in the
> > first place.
> >
> > Keplers' planetary laws described what previouslyt had been observed but
> > not derscroibable.
> >
> > Newton devised the laws of motion to ecxplain how the observed moving
> > bodies behaved, he did not predict that they woulfd behave that way!
> >
> > Einstien and Lorentz understoofd that the was someting wrong with
> > newtonian motion when it canme to high velocities and so puostulated the
> > consrtancyt of lightspeed. The above experiments seem to bear that out.
>
> Maybe, if they had considered that the speed of light would affect their
> observations, they would have come up with a different answer.
Spheres within the spheres solution again. The lightspeed was more
straightfoward and solved more problems. The other theory lost out to
the better theory.
>
> >
> > The effect of time dialation is not mearly an effect on clocks. It is
> > not a "trick" or something that happens to just the mechanical-ness of
> > the clocks in the experiment. It happens to YOU also. A person moving
> > ages slower than the observer that watched him, irregardless of the
> > direction in which he moved.
>
> Emmm, sorry, but how do you decide which person is moving relative to the
> other? If one stands still on the earth's surface, and the other walks
> contra to the earth's rotation, which of them ages more slowly? If one of
> them raises himself a foot above the Earth's surface and then remains
> stationary(relative to the centre of the Earth), does the chap who is
> stationary on the surface age more rapidly, or more slowly, than the other?
> This is the nub of the problem. For each of the observers, time is passing
> more slowly for the other. Therefore time has become completely 'broken'.
> It is passing faster and slower simultaneously for the same 'observer'.
You can solve the problem either way. You make an illogical arguement,
but I see a way out of the illogicalness.
Offer to ride with the guy we are observing instead of observing him
from this frame of reference, the one you argue is not moving, that we
are in. OK, so ride with him Then he has an observer that is not moving
relative to him. and solve the problem that way, ok?
We see this particular outcome because we analysed the situation from
our point of view, and we were at rest relative to the entire Milky way.
It just seems an easier analysis, but it does not have to be the only
one. Every time someone makes the mistake of wondering how come they
don't observe the opposit effect, it's because they haven't analysed
from truely the opposite point of view! So use a third party, traveling
along with the rocket guy. Those two see a completely different
situation. Let the guy leave the opposite side of the universe and come
to us. That problem analyses the same way. What happens?
>
> This sounds incredibly complicated, so let's just take your(widely accepted)
> statement "A person moving
> ages slower than the observer that watched him, irregardless of the
> direction in which he moved. "
> Either person can consider himself stationary, and therefore the the other
> must be ageing more slowly. As *either* person can be considered
> stationary, *both* must be ageing more slowly than the other,
> simultaneously. This is patently ridiculous.
It's not, just confusing. The only thing that is sort of ridiculous is
trying to put yourself in both places at the same time, and that's how
people get mixed up in this problem.
In each example the guy in motion had two fixed points: a start point
and an end point. Both those points were in the "stationary" frame of
reference", not because they did not move (maybe they did!) but because
we measured the motion of the traveler relative to those two points. But
we don't really have to.
The first "fixed" point was on earth when he left, the other "fixed"
point was on the other side of the galaxy, that point was fixed w.r.t.
earth, even if you want to consider that it was moving w.r.t. the
traveler, instead of the other way around.
You can think of the two points as fixed, since they are fixed w.r.t.
each other, but as soon as you ask the "poison question", as you did
above, you have to refer back to your frame of reference, otherwise you
try to change the frame of referenceof one of the points.
But You don't HAVE to analyse the problem that way. It works either way,
with the same result. It's just hadrer to understand (ha! If that's
possible).
Let the guy "float" in space and I'll move the galaxy past him. Why not?
He will still be forty years older when I get the other side of the
galaxy past him (he being fixed, floating in space) 100,000 years
later, from my point of view.
Time for me will still go by at the same rate, of course. The earth will
go around the sun 100,000 times. But the galaxy will pass the guy and
when the other side of the galaxy gets to the guy, he will be 40 years
older.
Now if I left him there, just in space, and instead I moved past him
from one end to the other, then I would be 40 years older, and he and
earth and the galaxy 100,000 years older. You have to maintain your
frame of reference, whichever one you start with you have to stick with.
What you did above was to start with earth as the first frame of
reference, the traveler as the second frame of reference. But the
destinations must be part of the first frame of reference. And then you
tried to change the destination to the traveler's frame of reference
saying that I moved relative to him and it. Not so. After he slows he
ship down and lands on the other side he re-enters the first frame of
reference and the problem then changes and he ages the same way we do.
It works!
>
> Regards
>
> Donal
> --
paul1martin
Dr...@mailroom.com wrote:
> I see your point, but I don't see that it can lead anywhere, >
>
I had my doubts about this thread going anywhere since its inception as
a 'sailing' thread.
It has about as much relivance as two bowling balls approaching one
another...one headed towards the pins and the other coming down the
return lane, both sending out sound waves at X miles per second. Or
maybe they could 'speak' to each other and as they got closer the sound
waves would pass at some point relative to their position on the alley.
The question would thus be at what point in time would the bowler hear
the one ball say to the other, "What has this to do with sailing?"
warm seas and dry decks to ya,
pm
d parker
many folks here, we can now sit back and learn something.
DP
"paul1martin" <paul1...@my-deja.com> wrote in message
news:8utqvu$t3n$1...@nnrp1.deja.com...
> In article <3A1260...@Armory.arm>,
> Dr...@mailroom.com wrote:
>
> > I see your point, but I don't see that it can lead anywhere, >
> >
Donal
Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A1260...@Armory.arm...
> Donal wrote:
<snip
> >
> > Emmm, sorry, but how do you decide which person is moving relative to
the
> > other? If one stands still on the earth's surface, and the other walks
<snip>
> You can solve the problem either way. You make an illogical arguement,
> but I see a way out of the illogicalness.
> Offer to ride with the guy we are observing instead of observing him
> from this frame of reference, the one you argue is not moving, that we
> are in. OK, so ride with him Then he has an observer that is not moving
> relative to him. and solve the problem that way, ok?
Why can't we step outside of this universe to perform our observations from
a neutral point?
Ok. Now imagine that he leaves the other side of the Galaxy and comes back
at the speed of light. He ages another 40 years. The Earth ages another
100,000 years. He arrives back to find that the Earth has aged 200,00
years. I think that you agree with this? The problem is that speed is
relative. From the perspective of our 'traveller', the Earth has receeded
at the speed of light and then come back at the speed of light. He now sees
that he has aged 200,000 years, and the Earth only has aged 80 years. So
when he gets back the Earth is both 80 years and 200,000 years older than he
is. ........ simultaneously....... and now back in the same frame of
reference. This is, I think, the nub of my problem with the whole theory.
Two different states must be able to exist simultaneously, if the constansy
of light is true.
Regards
Donal
--
Donal
The_navigator <the_na...@my-deja.com> wrote in message
news:8ut3bp$bpg$1...@nnrp1.deja.com...
> Hmm. Donal, accelaration is a vector quantity. For it to interact with a
> particle and induce a chnage in that particle the change should be
> reversible if the direction of the acceleration is reversed.
So if we take an oscillating particle and accelerate it one direction, its
period of oscillation will vary inversly to an acceleration in the other
direction?? I doubt it.
>If this is
> not the case then the particle must irreversibly change after
> acceleration and then it is then hard to see how your model works. Note
> that the time 'distortion' produced by flying a clock around is not
> reversable but acceleration is.
No, reversing acceleration, is in itself also acceleration. Think about it.
Acceleration is a *change* in velocity. This is because speed must be
relative to something. Therefore speed in itself is nothing. Constant
speed can also be thought of a "stationary". An object only has constant
speed if the measurer is is moving at a constant speed relative to the
object. To "reverse" acceleration, is to change the speed of movement.
Change of speed *is* Acceleration.
> Hence a big flaw in your initial premise
> I think. It is simple to accept SRT and consider time as one of the
> dimensions of (4 dimensional) space-time. Now at this point you will say
> Aha! but time cannot go backwards but we can move backwards. The answer
> is yes that is correct but it is our inability to 'see' and 'interact'
> with time that is a part of the problem. The second is that entropy must
> increase with time.
We started with a big bang, and now have a reasonably stable universe. At
the other end of the spectrum, electrons will tend towards the lowest level
of energy. Are you sure that you want to start me on Chaos Theory?
>So to reverse time you must be able to decrease
> entropy in the universe and this implies an even higher level (invisible
> to us) interaction than is possible with the realm of space-time...
You are just making it up here.
> Hence we would not be able to observe the effect of this interaction and
> so time reversal would not exist for us!
Regards
Donal
--
Dr Arm®
>
> Dr ArmŽ <Ar...@Armory.arm> wrote in message news:3A1260...@Armory.arm...
> > Donal wrote:
> <snip
> > >
> > > Emmm, sorry, but how do you decide which person is moving relative to
> the
> > > other? If one stands still on the earth's surface, and the other walks
> > You can solve the problem either way. You make an illogical arguement,
> > but I see a way out of the illogicalness.
> > Offer to ride with the guy we are observing instead of observing him
> > from this frame of reference, the one you argue is not moving, that we
> > are in. OK, so ride with him Then he has an observer that is not moving
> > relative to him. and solve the problem that way, ok?
>
> a neutral point?
You can, of course. So tell me, is the third frame of reference moving
with respect to the galaxy? Or is it fixed somewhere above the galaxy?
If it's fixed then it can have the same inertial reference as the first
frame of reference, the earth-galazy system, If it's moving along with
the traveler then it has the same frame of reference as the traveler
does. Anything else is another inertial frame and will have a
relativeistic effect wirth respect to the other two frames.
Either way, however you do the bookeeping, the problem will have the
same outcome. that's an important part of a legitmate solution to any
problem.
> Ok. Now imagine that he leaves the other side of the Galaxy and comes back
> at the speed of light. He ages another 40 years. The Earth ages another
> 100,000 years. He arrives back to find that the Earth has aged 200,00
> years. I think that you agree with this?
OK, it's in line with our example.
The problem is that speed is
> relative. From the perspective of our 'traveller', the Earth has receeded
> at the speed of light and then come back at the speed of light. He now sees
> that he has aged 200,000 years, and the Earth only has aged 80 years.
No. Again you forget that his motion was relative to the TWO points that
he departed from then arrived at. That is where you are getting
confused.
So
> when he gets back the Earth is both 80 years and 200,000 years older than he
> is. ........ simultaneously.......
No. We can identify either frame in motion, from either point of view,
but not a "hybrid" where we srart with one and then switch to the other.
I can move the galaxy under the traveler instead of moving the traveler
but I can't start out moving the traveler then deceid to move the galaxy
instead.
and now back in the same frame of
> reference. This is, I think, the nub of my problem with the whole theory.
> Two different states must be able to exist simultaneously, if the constansy
> of light is true.
No again you are changing the frame of reference. This time you're
starting out at the far "planet". But them you change to the traveler's
frame and expect the outcome to change. It won't, it's the same outcome.
You changed your frame in the middle of the journey, and that's why you
expect the reverse outcome.
da
>
> Regards
>
> Donal
> --
Dr Arm®
> > Hmm. Donal, accelaration is a vector quantity. For it to interact with a
> > particle and induce a chnage in that particle the change should be
> > reversible if the direction of the acceleration is reversed.
>
> period of oscillation will vary inversly to an acceleration in the other
> direction?? I doubt it.
According to the general relativity theory it will. May I jump in here?
The Newtonian principle of the equivalance of inertial mass and
gravitational mass (the same principle that explains why we have two
roughly equal tides every day instead of one) says that it doesn't
matter whether you accelerate or are in a gravitational field. The
atomic clock that slows down in the presence of a large gravitational
field will slow down the same amount during an equivalent acceleration.
It is not a mechanical "trick". the trick is in the warpage of
space-time near a large gravitational mass, or equivalantly a high
acceleration.
>
> >If this is
> > not the case then the particle must irreversibly change after
> > acceleration and then it is then hard to see how your model works. Note
> > that the time 'distortion' produced by flying a clock around is not
> > reversable but acceleration is.
> No, reversing acceleration, is in itself also acceleration. Think about it.
Yes, of course it is. More specifically, reversing or changing velocity
is an acceleration. this is true even when the body does not change
speed. Thus the earth "accelerates" around the sun since it is
constatntly changing it's direction, hence it's inertia. And when you
change inertia, you accelerate.
> Acceleration is a *change* in velocity. This is because speed must be
> relative to something. Therefore speed in itself is nothing. Constant
> speed can also be thought of a "stationary". An object only has constant
> speed if the measurer is is moving at a constant speed relative to the
> object.
Yes all true. Basic physice, 101.
To "reverse" acceleration, is to change the speed of movement.
> Change of speed *is* Acceleration.
Yes. As is change of direction.
>
> > Hence a big flaw in your initial premise
> > I think. It is simple to accept SRT and consider time as one of the
> > dimensions of (4 dimensional) space-time. Now at this point you will say
> > Aha! but time cannot go backwards but we can move backwards. The answer
> > is yes that is correct but it is our inability to 'see' and 'interact'
> > with time that is a part of the problem. The second is that entropy must
> > increase with time.
>
> We started with a big bang, and now have a reasonably stable universe. At
> the other end of the spectrum, electrons will tend towards the lowest level
> of energy.
Even so, entrophy is still increasing. Matter is decaying.
> Are you sure that you want to start me on Chaos Theory?
Yes, explain it to me.
>
> >So to reverse time you must be able to decrease
> > entropy in the universe and this implies an even higher level (invisible
> > to us) interaction than is possible with the realm of space-time...
Personally I agree with this, for the same thermodynamic reason as well
as others.
da
Scott
Douglas S. King wrote .
>
>And what I like about the South is real barbeque.
MMmmmm southern BBQ, w/coleslaw, & *real* icedtea, and grits w/sausage
gravy & bisquits, mmmmmmmm
>I also get a laugh out of
>asking all the newly arrived Yankees "So, it it hot enough for you?" and
last week in VA, it was in the 50s and I laughed at my buddy when he put on
a heavy jacket.
Scott Vernon, from Southern PA