Simultaneity of Relativity
mpc755
relative to the train, this is what will occur in Einstein's train
thought experiment:
YBM
Your new absurdities don't have much success, so you try again the
old ones ?
PD
Cute.
Now, keep in mind that the gedanken is an explanatory tool to help
understand what relativity says. It is in no way an experiment. Nor
has there ever been an experiment done involving a train to test
relativity's claims.
However, there HAVE been experiments done that are similar in concept
to the train set-up, at least in terms of the underlying physics.
And what's interesting is that the experimental results are consistent
with relativity and not with the scheme that you've drawn. Already.
papa...@gmail.com
This is a very good piece of work of yours, that provides a very good
proof of Einstein's relativity of simultaneity.
You describe what happens in both the train and the embankment frames.
a) Considering the events as observed by M' on the train, the light
fronts coming from points A' and B' arrive to the location of M'
simultaneously, while clearly it is also seen that, as observed by M,
the light front coming from point A' gets to the location of M well
BEFORE arriving to the location of M', while the light front coming
from point B' gets to the location of M well AFTER passing through the
location of M'. Very well done!!!
b) Now, you also nicely show the situation as seen from the point of
view of M. Considering the events as observed by M on the embankment,
the light fronts coming from points A and B arrive to the location of
M simultaneously, while clearly it is also seen that, as observed by
M', the light front coming from point A gets to the location of M'
well AFTER arriving to the location of M, while the light front coming
from point B gets to the location of M' well BEFORE passing through
the location of M.
Once again, you have proved beyond any doubt the relativity of
simultaneity according to Einstein gedanken. Congratultions.
Miguel Rios
mpc755
Yes, because the tests are performed within a single aether.
mpc755
What I am displaying is not Einstein's Relativity of Simultaneity.
In Einstein's Relativity of Simultaneity ALL of the light from the
lightning strike at A/A' reaches M simultaneously and ALL of the light
from the lightning strike A/A' reaches M' simultaneously, and ALL of
the light from lightning strike at B/B' reaches M simultaneously, and
ALL of the light from the lightning strike at B/B' reaches M'
simultaneously.
This is NOT what I am showing.
But thanks for agreeing with Simultaneity of Relativity.
PD
No, that is NOT what Einstein's train gedanken says happens, at all.
Good heavens. It appears you don't know what SR says.
Right on your YouTube video page you'll see a much better video that
DOES say what Einstein's train gedanken says. You'll see it's much
different than what you just wrote above.
papa...@gmail.com
No! you are as always ignorant of even what Einstein gedanken says,
so...
You are showing four (4) events or flashes instead of the two (2)
flashes that Einstein used. And, of course, the relativity of
simultaneity means that those two events while being simultaneous for
one of the observers (M for instance), will most definitely not be
simultaneous for the other observer M', and vice versa.
This was already discussed some months ago, so you are clearly trying
to resurrect a dead cow here.
Miguel Rios
mpc755
I think you misunderstood what I was saying. The only point I am
trying to make to the other poster is the light from A' does not reach
M prior to the light from A reaching M in Einstein's train thought
experiment. In Einstein's Relativity of Simultaneity the lightning
strike at A/A' is a single event and ALL of the light from the
lightning strike at A/A' reaches M simultaneously.
In Simultaneity of Relativity the light from A' reaches M prior to the
light from A reaching M.
mpc755
You do not understand Einstein's Relativity of Simultaneity.
In Einstein's Relativity of Simultaneity the lightning strike at A/A'
is a single event and all of the light from A/A' will reach M
simultaneously.
This is not what is occurring in Simultaneity of Relativity. In
Simultaneity of Relativity, the light from the lightning strike at A'
PD
So is your train picture. And the experimental results are not
consistent with your movie.
papa...@gmail.com
No it is you who, clearly, does not understand any physics.
If you now are asserting that the strikes are simultaneous at points A
and A', then your video is totally bogus since you are clearly showing
two circles growing one from point A and the other from point A' and
hence they are not moving at the same speed.
Miguel Rios
PD
No sir. The lighting strikes at A/A' are two separate events. You have
a mistaken idea of what "event" means in relativity. An event, as
defined for this purpose, is something that happens at a particular
place and a particular time, not just at a particular time. And since
A and A' happen at different places, they are separate events.
Secondly, the gedanken doesn't say that the light doesn't arrive at M
simultaneously. It says that it doesn't arrive at M' simultaneously.
It's apparent that you don't know what the train gedanken description
is. Have you tried to read it?
mpc755
The light from A/A' reaches M simultaneously in Einstein's Train
Thought Experiment. If you do not understand this point in Einstein's
Train Thought Experiment when discussing Relativity of Simultaneity,
you are clueless.
mpc755
Yes, the lightning strike at A/A' occurs simultaneously because it is
a single lightning strike that just happens to hit at A and A'
simultaneously.
The light from the lightning strike at A is moving through the aether
which is stationary relative to the embankment and the light from the
lightning strike at A' is moving through the aether which is
stationary relative to the train.
PD
Yes, that's what I JUST SAID. I gather you have a difficult time
reading for comprehension.
However the light from A/A' does not reach M' at the same time.
Also, if this were viewed from M's view, the two events at A and A'
would not be simultaneous.
> If you do not understand this point in Einstein's
> Train Thought Experiment when discussing Relativity of Simultaneity,
> you are clueless.
>
>
>
>
>
> > > In Simultaneity of Relativity the light from A' reaches M prior to the
> > > light from A reaching M.
>
> > > > > This is NOT what I am showing.
>
> > > > > But thanks for agreeing with Simultaneity of Relativity.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -
mpc755
How can the light from A/A' reach M simultaneously and not reach M'
simultaneously?
PD
>
> - Show quoted text -
Sorry, I've fouled this up.
What Einstein's gedanken says is that the light from A/A' and the
light from B/B' arrive simultaneously at M and NOT simultaneously at
M'.
And if this were viewed from M', because the propagation toward M' is
c from either A/A' or B/B', then it would be clear that events at A
and B were not simultaneous.
PD
mpc755
OK, at least you now understand Relativity of Simultaneity.
In Simultaneity of Relativity, both frames are equal. Consider the
aether to be 'entrained' by the embankment in the embankment frame of
reference and for the aether to be 'entrained' by the train in the
train frame of reference.
Where the light travels from is dependent on how the frame of
reference is interacting with the aether. Since the aether is
stationary in the embankment reference frame the light travels from A
and B to M and since the aether is stationary in the train reference
frame the light travels from A' and B' to M' simultaneously.
The light from A and B reaches M and the light from A' and B' reaches
M' simultaneously.
PD
That's all well and good, but experiment agrees with Einstein, not
with your picture.
> Consider the
> aether to be 'entrained' by the embankment in the embankment frame of
> reference and for the aether to be 'entrained' by the train in the
> train frame of reference.
OK, but the train observer could well be sitting on top of the train
out in the open air, right along with the air that is surrounding the
embankment.
So unless you've got overlapping aethers, one passing through the
other, then there would have to be a boundary between the two moving
masses of aether, where they are rubbing up against each other. And in
that case, there would be a region of aether in between where it is
moving somewhat in between what the two entrained aethers are moving.
And then just by moving, say, the embankment observer a little closer
to the train, or the train observer a little to one side, then you'd
start seeing the effect of the aether moving at a speed somewhat in
between. However, this is not observed in equivalent experiments.
This is what I mean by following the implications of an idea all the
way through to look for *uniquely distinguishing* predictions. I've
just given an example of a clear implication of AD, one that would be
testable. And unfortunately, it doesn't match experiment. So it's
gotta be wrong.
>
> Where the light travels from is dependent on how the frame of
> reference is interacting with the aether. Since the aether is
> stationary in the embankment reference frame the light travels from A
> and B to M and since the aether is stationary in the train reference
> frame the light travels from A' and B' to M' simultaneously.
>
> The light from A and B reaches M and the light from A' and B' reaches
> M' simultaneously.
Nope, that doesn't match what happens in related experiments. Sorry.
mpc755
How would you know? You just figured out what Relativity of
Simultaneity is two minutes ago.
> > Consider the
> > aether to be 'entrained' by the embankment in the embankment frame of
> > reference and for the aether to be 'entrained' by the train in the
> > train frame of reference.
>
> OK, but the train observer could well be sitting on top of the train
> out in the open air, right along with the air that is surrounding the
> embankment.
> So unless you've got overlapping aethers, one passing through the
> other, then there would have to be a boundary between the two moving
> masses of aether, where they are rubbing up against each other. And in
> that case, there would be a region of aether in between where it is
> moving somewhat in between what the two entrained aethers are moving.
> And then just by moving, say, the embankment observer a little closer
> to the train, or the train observer a little to one side, then you'd
> start seeing the effect of the aether moving at a speed somewhat in
> between. However, this is not observed in equivalent experiments.
>
Post a link to the experiments you are referring to.
> This is what I mean by following the implications of an idea all the
> way through to look for *uniquely distinguishing* predictions. I've
> just given an example of a clear implication of AD, one that would be
> testable. And unfortunately, it doesn't match experiment. So it's
> gotta be wrong.
>
Experiments like de Sitter and the double star?
'De Sitter double star experiment'
http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
'the "fast" light given off during approach would be able to catch up
with and even overtake "slow" light emitted earlier during a
recessional part of the star's orbit, and the star would present an
image that was scrambled and out of sequence.'
This is an oversimplification of what is occurring. The aether around
each star is entrained by the star, so emitter theory is in effect
close to the star.
But the aether surrounding both stars acts as a singleton and the
aether travels at 'c' through this aether.
That is why the light from double stars is not scrambled.
PD
:>)
Well, I certainly did have difficulty explaining it right at first.
But the experimental stuff has been figured out a long time ago.
>
>
>
>
> > > Consider the
> > > aether to be 'entrained' by the embankment in the embankment frame of
> > > reference and for the aether to be 'entrained' by the train in the
> > > train frame of reference.
>
> > OK, but the train observer could well be sitting on top of the train
> > out in the open air, right along with the air that is surrounding the
> > embankment.
> > So unless you've got overlapping aethers, one passing through the
> > other, then there would have to be a boundary between the two moving
> > masses of aether, where they are rubbing up against each other. And in
> > that case, there would be a region of aether in between where it is
> > moving somewhat in between what the two entrained aethers are moving.
> > And then just by moving, say, the embankment observer a little closer
> > to the train, or the train observer a little to one side, then you'd
> > start seeing the effect of the aether moving at a speed somewhat in
> > between. However, this is not observed in equivalent experiments.
>
> Post a link to the experiments you are referring to.
Google "experimental basis for relativity"
>
> > This is what I mean by following the implications of an idea all the
> > way through to look for *uniquely distinguishing* predictions. I've
> > just given an example of a clear implication of AD, one that would be
> > testable. And unfortunately, it doesn't match experiment. So it's
> > gotta be wrong.
>
> Experiments like de Sitter and the double star?
No. That has to do with something else entirely.
That has to do with a test that distinguishes ballistic emission
theory and relativity.
Nothing to do with simultaneity.
>
> 'De Sitter double star experiment'http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
>
> 'the "fast" light given off during approach would be able to catch up
> with and even overtake "slow" light emitted earlier during a
> recessional part of the star's orbit, and the star would present an
> image that was scrambled and out of sequence.'
>
> This is an oversimplification of what is occurring. The aether around
> each star is entrained by the star, so emitter theory is in effect
> close to the star.
>
> But the aether surrounding both stars acts as a singleton and the
> aether travels at 'c' through this aether.
>
> That is why the light from double stars is not scrambled.
>
>
>
>
>
> > > Where the light travels from is dependent on how the frame of
> > > reference is interacting with the aether. Since the aether is
> > > stationary in the embankment reference frame the light travels from A
> > > and B to M and since the aether is stationary in the train reference
> > > frame the light travels from A' and B' to M' simultaneously.
>
> > > The light from A and B reaches M and the light from A' and B' reaches
> > > M' simultaneously.
>
> > Nope, that doesn't match what happens in related experiments. Sorry.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
mpc755
If you say this is not observed in equivalent experiments, you should
be willing and able to backup up such a statement with specifics.
But, since you just figured out what Relativity of Simultaneity is
five minutes ago, its understandable you can't backup the claims you
make.
>
>
> > > This is what I mean by following the implications of an idea all the
> > > way through to look for *uniquely distinguishing* predictions. I've
> > > just given an example of a clear implication of AD, one that would be
> > > testable. And unfortunately, it doesn't match experiment. So it's
> > > gotta be wrong.
>
> > Experiments like de Sitter and the double star?
>
> No. That has to do with something else entirely.
> That has to do with a test that distinguishes ballistic emission
> theory and relativity.
> Nothing to do with simultaneity.
>
Simultaneity of Relativity is emission theory in an entrained aether.
doug
mpc755 wrote:
So do you need us to show you how to use google? I know you do
not know any physics but I thought you might know how to do
a search.
> But, since you just figured out what Relativity of Simultaneity is
> five minutes ago, its understandable you can't backup the claims you
> make.
>
Well, the crank is getting testy. You are too lazy to use google to
look up anything and then you make stupid statements like this.
PD
Such cheesy baiting.
If you actually do the search I recommended, and you click on the
FIRST link it returns, you'll have a lovely list of experiments.
If you cannot do even this without whining, is it an indicator that
you are hopelessly lazy or hopelessly incompetent?
>
>
>
> > > > This is what I mean by following the implications of an idea all the
> > > > way through to look for *uniquely distinguishing* predictions. I've
> > > > just given an example of a clear implication of AD, one that would be
> > > > testable. And unfortunately, it doesn't match experiment. So it's
> > > > gotta be wrong.
>
> > > Experiments like de Sitter and the double star?
>
> > No. That has to do with something else entirely.
> > That has to do with a test that distinguishes ballistic emission
> > theory and relativity.
> > Nothing to do with simultaneity.
>
> Simultaneity of Relativity is emission theory in an entrained aether.
No, it's not. In your theory the speed of light is relative to the
aether. In ballistic theory it is relative to the source.
Plus the fact, just renaming AD "Simultaneity of Relativity" doesn't
link simultaneity and a test of ballistic emission theory, any more
than renaming Newton's 2nd law "Cell Apoptosis" would make Newton's
2nd law about biolgy.
>
>
>
>
>
> > > 'De Sitter double star experiment'http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
>
> > > 'the "fast" light given off during approach would be able to catch up
> > > with and even overtake "slow" light emitted earlier during a
> > > recessional part of the star's orbit, and the star would present an
> > > image that was scrambled and out of sequence.'
>
> > > This is an oversimplification of what is occurring. The aether around
> > > each star is entrained by the star, so emitter theory is in effect
> > > close to the star.
>
> > > But the aether surrounding both stars acts as a singleton and the
> > > aether travels at 'c' through this aether.
>
> > > That is why the light from double stars is not scrambled.
>
> > > > > Where the light travels from is dependent on how the frame of
> > > > > reference is interacting with the aether. Since the aether is
> > > > > stationary in the embankment reference frame the light travels from A
> > > > > and B to M and since the aether is stationary in the train reference
> > > > > frame the light travels from A' and B' to M' simultaneously.
>
> > > > > The light from A and B reaches M and the light from A' and B' reaches
> > > > > M' simultaneously.
>
> > > > Nope, that doesn't match what happens in related experiments. Sorry.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
mpc755
If the train is half full of water and the water is stationary in the
train and you drop pebbles at A' and B', the waves from A' and B' will
reach M' simultaneously.
If the embankment is half full of water and the water is stationary
relative to the embankment and you drop pebbles into the water at A
and B, the waves from A and B will reach M simultaneously.
If you drop pebbles into the water at A and A' simultaneously and drop
pebbles into B and B' simultaneously, if the waves from A and B reach
M simultaneously, the waves from A' and B' will reach M'
simultaneously.
doug
mpc755 wrote:
We notice that mpc did not even try to do a google search. It looks
like he is both lazy and incompetent.
PD
And this goes back to what I was telling you earlier. Suppose the
train observer is on top of the train, so that the water that the
train observer is immersed in is not separated from the water that the
embankment observer is immersed in. Now, where is the boundary between
the two batches of water?
>
>
>
> > Plus the fact, just renaming AD "Simultaneity of Relativity" doesn't
> > link simultaneity and a test of ballistic emission theory, any more
> > than renaming Newton's 2nd law "Cell Apoptosis" would make Newton's
> > 2nd law about biolgy.
>
> > > > > 'De Sitter double star experiment'http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
>
> > > > > 'the "fast" light given off during approach would be able to catch up
> > > > > with and even overtake "slow" light emitted earlier during a
> > > > > recessional part of the star's orbit, and the star would present an
> > > > > image that was scrambled and out of sequence.'
>
> > > > > This is an oversimplification of what is occurring. The aether around
> > > > > each star is entrained by the star, so emitter theory is in effect
> > > > > close to the star.
>
> > > > > But the aether surrounding both stars acts as a singleton and the
> > > > > aether travels at 'c' through this aether.
>
> > > > > That is why the light from double stars is not scrambled.
>
> > > > > > > Where the light travels from is dependent on how the frame of
> > > > > > > reference is interacting with the aether. Since the aether is
> > > > > > > stationary in the embankment reference frame the light travels from A
> > > > > > > and B to M and since the aether is stationary in the train reference
> > > > > > > frame the light travels from A' and B' to M' simultaneously.
>
> > > > > > > The light from A and B reaches M and the light from A' and B' reaches
> > > > > > > M' simultaneously.
>
> > > > > > Nope, that doesn't match what happens in related experiments. Sorry.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
PD
If it helps, MPC, Einstein's train gedanken can just as well take
place on open, flat-bed cars.
>
>
>
> > Plus the fact, just renaming AD "Simultaneity of Relativity" doesn't
> > link simultaneity and a test of ballistic emission theory, any more
> > than renaming Newton's 2nd law "Cell Apoptosis" would make Newton's
> > 2nd law about biolgy.
>
> > > > > 'De Sitter double star experiment'http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
>
> > > > > 'the "fast" light given off during approach would be able to catch up
> > > > > with and even overtake "slow" light emitted earlier during a
> > > > > recessional part of the star's orbit, and the star would present an
> > > > > image that was scrambled and out of sequence.'
>
> > > > > This is an oversimplification of what is occurring. The aether around
> > > > > each star is entrained by the star, so emitter theory is in effect
> > > > > close to the star.
>
> > > > > But the aether surrounding both stars acts as a singleton and the
> > > > > aether travels at 'c' through this aether.
>
> > > > > That is why the light from double stars is not scrambled.
>
> > > > > > > Where the light travels from is dependent on how the frame of
> > > > > > > reference is interacting with the aether. Since the aether is
> > > > > > > stationary in the embankment reference frame the light travels from A
> > > > > > > and B to M and since the aether is stationary in the train reference
> > > > > > > frame the light travels from A' and B' to M' simultaneously.
>
> > > > > > > The light from A and B reaches M and the light from A' and B' reaches
> > > > > > > M' simultaneously.
>
> > > > > > Nope, that doesn't match what happens in related experiments. Sorry.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
papa...@gmail.com
Again, you have not the slightest idea of what you are talking about.
What Einstein gedanken says is quite clear: observer M on the
embankment is right on the midle of the distance between points A and
B and when the strikes hit both A and B he will later receive both
light signals simultaneously. Then he ask the readers if observer M'
on the train will observe the same and he proved that he will not.
When the strikes happened, M' (moving at a speed v=0.6c let us say)
was passing just in front of M. So the spacetime coordinates of the
same event are given by the Lorentz transformation equations:
x' = gamma (x - vt) ; t’ = gamma (t - vx/c^2)
where gamma=1/ (sqrt(1- v^2/c^2))=1.25 since v=0.6c
So in the embankment frame, the two strikes were at t=0 and
x_A=-100000km, x_B=+100000km, so it is quite evident that:
x_A'=-125000km, t_A'=+0.25sec are the coordinates of point A' on the
train
x_B'=+125000km, t_B'=-0.25sec are the coordinates of point B' on the
train
So as the observer M received both light signals at the same time,
meaning the strikes hit at the same time on the embankment frame, the
same event were not at the same time on the train frame and that is
all to this gedanken.
Miguel Rios
mpc755
The water is stationary relative to the embankment and the train is
moving along under the water and not affecting the water. Pebbles are
dropped at A/A' and B/B'. The wave from B/B' travels from B to M'. The
waves from A and B and reach M simultaneously. The wave from A reaches
M'. A' and B' are irrelevant in this scenario.
The water is stationary relative to the train. Pebbles are dropped at
A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
reach M' simultaneously. The wave from B' reaches M. A and B are
irrelevant in this scenario.
'Fizeau experiment'
http://en.wikipedia.org/wiki/Fizeau_experiment
mpc755
Yes, in Relativity of Simultaneity the lightning strike at A/A' occurs
at a different time in the embankment frame of reference than it does
in the train frame of reference. Same with the lightning strike at B/
B'. But in each frame of reference, in Relativity of Simultaneity,
there are still only two lightning strikes, one at A/A' and one at B/
B'.
In Simultaneity of Relativity, even though there are two lightning
strikes, one at A/A' and one at B/B', the light from the lightning
strike at A travels from A to the destinations. Same for the lightning
strikes at A', B, and B'. The light from each lightning strike is
effected by the aether that is stationary in each reference frame and
travels different distances to the destinations.
PD
And notice that the waves from A and B do not arrive at M' at the same
time.
> A' and B' are irrelevant in this scenario.
Well, strictly speaking they are in the Einstein gedanken too, because
there really are only two lightning strikes.
It would be really great if you could learn a bit more about what the
Einstein gedanken really says before you waste a lot of time creating
animations about something completely irrelevant and then demonstrate
that you really didn't understand the Einstein gedanken in the first
place.
>
> The water is stationary relative to the train. Pebbles are dropped at
> A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> reach M' simultaneously. The wave from B' reaches M. A and B are
> irrelevant in this scenario.
OK, but there are really only two lightning strikes, and the water
doesn't really have time to switch from being stationary relative to
the embankment to being stationary relative to the train.
Einstein's gedanken is about ONE pair of events (the lightning
strikes) and what happens to the light as observed by M and M' for
that ONE case, not two cases.
>
> 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment
>
>
>
> > > > Plus the fact, just renaming AD "Simultaneity of Relativity" doesn't
> > > > link simultaneity and a test of ballistic emission theory, any more
> > > > than renaming Newton's 2nd law "Cell Apoptosis" would make Newton's
> > > > 2nd law about biolgy.
>
> > > > > > > 'De Sitter double star experiment'http://en.wikipedia.org/wiki/De_Sitter_double_star_experiment
>
> > > > > > > 'the "fast" light given off during approach would be able to catch up
> > > > > > > with and even overtake "slow" light emitted earlier during a
> > > > > > > recessional part of the star's orbit, and the star would present an
> > > > > > > image that was scrambled and out of sequence.'
>
> > > > > > > This is an oversimplification of what is occurring. The aether around
> > > > > > > each star is entrained by the star, so emitter theory is in effect
> > > > > > > close to the star.
>
> > > > > > > But the aether surrounding both stars acts as a singleton and the
> > > > > > > aether travels at 'c' through this aether.
>
> > > > > > > That is why the light from double stars is not scrambled.
>
> > > > > > > > > Where the light travels from is dependent on how the frame of
> > > > > > > > > reference is interacting
>
> ...
>
> read more »
mpc755
Yes, because the water is stationary relative to the embankment. In
this scenario, the embankment is the preferred frame.
For Einstein's train thought experiment to be truly relative, there
can be no preferred frame.
Therefore, the water must be stationary relative to the embankment in
the embankment frame of reference and stationary relative to the train
in the train reference frame.
In this scenario, my animation holds in the light from A and B reaches
M and the light from A' and B' reaches M' simultaneously.
>
>
> > The water is stationary relative to the train. Pebbles are dropped at
> > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > reach M' simultaneously. The wave from B' reaches M. A and B are
> > irrelevant in this scenario.
>
> OK, but there are really only two lightning strikes, and the water
> doesn't really have time to switch from being stationary relative to
> the embankment to being stationary relative to the train.
>
The water doesn't have to switch. The water is stationary relative to
the embankment in the embankment frame of reference and the water is
stationary relative to the train in the train frame of reference.
There is a single lightning strike at A/A' but A in on the embankment
and A' is on the train. Likewise with the lightning strike at B/B'.
> Einstein's gedanken is about ONE pair of events (the lightning
> strikes) and what happens to the light as observed by M and M' for
> that ONE case, not two cases.
>
That is why I am saying Einstein is incorrect. He is trying to have it
both ways. He wants to have a single lightning strike in two reference
frames where the reference frames are not equal.
If his train thought experiment was correct with equal reference
frames, the light from the lightning strikes at A and B would reach M
and the light from the lightning strikes at A' and B' would reach M'
simultaneously:
http://www.youtube.com/watch?v=jyWTaXMElUk
> > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment
>
PD
Yes! And notice that, because the train cars are open, flatbed cars,
you have to satisfy both criteria at the same time!
Here's where the fun starts. So if there is an aether (or water as you
want to analogize), it has to be stationary with respect to the
embankment AND to the train, at the same time. Not different
scenarios. At the same time.
>
> In this scenario, my animation holds in the light from A and B reaches
> M and the light from A' and B' reaches M' simultaneously.
No, certainly not. Because it's the same medium.
The embankment observer notes that the light from A and B reaches M'
at different times.
The train observer has to agree with that. Nature doesn't produce two
different measurable outcomes at the same time. There is only one.
Either the light arrives at the same time at M' or it doesn't. The
embankment observer and the train observer have to agree which one of
those two it was.
It appears that you are having a slow time getting a grip on what the
Einstein gedanken really says.
>
>
>
> > > The water is stationary relative to the train. Pebbles are dropped at
> > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > > reach M' simultaneously. The wave from B' reaches M. A and B are
> > > irrelevant in this scenario.
>
> > OK, but there are really only two lightning strikes, and the water
> > doesn't really have time to switch from being stationary relative to
> > the embankment to being stationary relative to the train.
>
> The water doesn't have to switch. The water is stationary relative to
> the embankment in the embankment frame of reference and the water is
> stationary relative to the train in the train frame of reference.
But these aren't two different sequences of events. It's the same
train, the same two lightning strikes, and there is only one pool of
water surrounding the embankment and the open train cars. So you tell
me, how can the water be stationary relative to the train AND
stationary relative to the embankment?
>
> There is a single lightning strike at A/A' but A in on the embankment
> and A' is on the train. Likewise with the lightning strike at B/B'.
>
> > Einstein's gedanken is about ONE pair of events (the lightning
> > strikes) and what happens to the light as observed by M and M' for
> > that ONE case, not two cases.
>
> That is why I am saying Einstein is incorrect. He is trying to have it
> both ways. He wants to have a single lightning strike in two reference
> frames where the reference frames are not equal.
What do you mean "equal"?
The same sequence of events live in a bunch of reference frames all at
once.
If a sailor falls from the crow's nest of a ship, you can look at that
sequence of events from the deck of the ship or you can look at that
SAME sequence of events from the shore. This is looking at the SAME
sequence of events from two different reference frames.
In the reference frame of the ship, the sailor falls in a straight
line down and lands at the bottom of the mast. In the reference frame
of the shore (because the ship is moving relative to the shore), the
sailor falls in a parabola, landing some distance to one side of where
he left the crow's nest. This is what Galileo understood and used as
an example to explain.
There is only one sailor and he only fell once. The sailor travels in
a straight line AND in a parabola AT THE SAME TIME. It's just that the
path is dependent on the reference frame.
>
> If his train thought experiment was correct with equal reference
> frames, the light from the lightning strikes at A and B would reach M
> and the light from the lightning strikes at A' and B' would reach M'
> simultaneously:
But they DON'T, in real life, as determined in experiment.
mpc755
Yes, the light from A and B reaches M' at different times, but the
light from A' and B' reaches M' simultaneously.
> The train observer has to agree with that.
Yes, the train observer agrees the light from A and B reaches him at
different times, but the light from A' and B' reaches him
simultaneously.
> Nature doesn't produce two
> different measurable outcomes at the same time. There is only one.
> Either the light arrives at the same time at M' or it doesn't. The
> embankment observer and the train observer have to agree which one of
> those two it was.
>
> It appears that you are having a slow time getting a grip on what the
> Einstein gedanken really says.
>
>
>
> > > > The water is stationary relative to the train. Pebbles are dropped at
> > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > > > reach M' simultaneously. The wave from B' reaches M. A and B are
> > > > irrelevant in this scenario.
>
> > > OK, but there are really only two lightning strikes, and the water
> > > doesn't really have time to switch from being stationary relative to
> > > the embankment to being stationary relative to the train.
>
> > The water doesn't have to switch. The water is stationary relative to
> > the embankment in the embankment frame of reference and the water is
> > stationary relative to the train in the train frame of reference.
>
> But these aren't two different sequences of events. It's the same
> train, the same two lightning strikes, and there is only one pool of
> water surrounding the embankment and the open train cars. So you tell
> me, how can the water be stationary relative to the train AND
> stationary relative to the embankment?
>
It's the same two lightning strikes, but it is occurring at A on the
embankment and A' on the train.
You can have a bucket of water that is stationary on the embankment
and a bucket of water that is stationary on the train.
I think we can agree on the following:
Pebbles are dropped at A, A', B, and B' simultaneously as determined
by observers. The water on the embankment is stationary relative to
the embankment in the embankment frame of reference. The water on the
train is stationary relative to the train in the train frame of
reference.
If the waves from A and B reach M simultaneously, then the waves from
A' and B' reach M' simultaneously. The waves from A and B reach M and
the waves from A' and B' reach M' at the same time.
If instead of pebbles being dropped into the water, we now have
flashes occur at A, A', B, and B' simultaneously as determined by
observers, then due to the results of experiments with water and light
performed by Fizeau and others, then if the light from A and B reaches
M simultaneously then the light from A' and B' reaches M'
simultaneously and the light from A and B reaches M and the light from
A' and B' reaches M' at the same time.
Now, instead of water being stationary relative to the embankment in
the embankment frame of reference and water being stationary relative
to the train in the train frame of reference, we have aether
stationary relative to the embankment in the embankment frame of
reference and aether stationary relative to the train in the train
frame of reference, the results for simultaneously flashes of light at
A, A', B, and B' will be the same in aether as described above for
flashes in water.
glird
>
< If the aether is stationary relative to the
embankment and stationary relative to the train, this is what will
http://www.youtube.com/watch?v=jyWTaXMElUk >
Your illustration doesn't fit the above conditions, which require
the train to be stationary wrt the embankment. (In the demo, the train
- and its aether - are moving wrt to the track and its aether. Since
there is only one material medium in otherwise empty space, the demo
contradicts reality.)
glird
mpc755
Why must the train be stationary wrt the embankment? If you are
implying the aether is stationary relative to the embankment and not
stationary relative to the train, then you are making the embankment
the preferred frame. If that is the case, then the lightning strikes
at A' and B' on the train are irrelevant and the light from B will
reach M' prior to the light from A in all frames of reference.
That is not what Einstein is implying. Einstein is implying the
embankment frame of reference and the train frame of reference are
equal in all respects. This means, however the aether exists in the
embankment frame of reference it must also exist the same way in the
train frame of reference.
This means if the aether is stationary relative to the embankment in
the embankment frame of reference than the aether must also be
stationary relative to the train in the train frame of reference.
There is only one material medium in otherwise empty space, but you
are placing unnecessary and incorrect assumptions on it to think it
cannot behave as all other mediums do. Any medium on the train moves
with the train. Aether is no different.
mpc755
> On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > > > > > > > > Sorry, I've fouled this up.
>
>
I missed where you say it is an open train car. If it is an open train
car, which implies the water is stationary relative to the embankment
and not stationary relative to the train, then the light from the
lightning strike at A and B will not reach the observer at M'
simultaneously and neither will the light from the lightning strikes
at A' and B'. If the water is stationary relative to the embankment,
the light from the lightning strike at B' will travel from B to M' and
arrive prior to the light from the lightning strike at A' and will
travel from A to M'. A' and B' are irrelevant if we are discussing
'open train cars' which implies the water is stationary relative to
the embankment.
You can replace 'water' with 'aether' in the above paragraph and the
same outcome will occur.
PD
A and A' are a single strike. B and B' are a single strike.
The light from A/A' travels through the *same medium* that the
embankment and the open flatbed train cars are immersed in. The light
from B/B' does the same thing.
So how does the light, coming from a single lightning strike (A/A'),
traveling through a common medium, arrive at the same observer M' both
simultaneously and not simultaneously as the light from B/B'? The
observer M' either sees the flashes from the strikes at his eyes at
the same time or he doesn't. He can't do both.
>
> > The train observer has to agree with that.
>
> Yes, the train observer agrees the light from A and B reaches him at
> different times, but the light from A' and B' reaches him
> simultaneously.
A and A' are ONE lightning strike. B and B' are ONE lightning strike.
Let's say that the ONE lightning strike at A/A' is greenish, and the
lightning strike at B/B' is yellowish.
The question is simple. There is a guy M' who is going to see the two
lightning flashes. Does he see the yellowish and greenish ones at the
same time or at different times? There can only be one answer, as this
is something that the guy can write down when it happens.
>
> > Nature doesn't produce two
> > different measurable outcomes at the same time. There is only one.
> > Either the light arrives at the same time at M' or it doesn't. The
> > embankment observer and the train observer have to agree which one of
> > those two it was.
>
> > It appears that you are having a slow time getting a grip on what the
> > Einstein gedanken really says.
>
> > > > > The water is stationary relative to the train. Pebbles are dropped at
> > > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > > > > reach M' simultaneously. The wave from B' reaches M. A and B are
> > > > > irrelevant in this scenario.
>
> > > > OK, but there are really only two lightning strikes, and the water
> > > > doesn't really have time to switch from being stationary relative to
> > > > the embankment to being stationary relative to the train.
>
> > > The water doesn't have to switch. The water is stationary relative to
> > > the embankment in the embankment frame of reference and the water is
> > > stationary relative to the train in the train frame of reference.
>
> > But these aren't two different sequences of events. It's the same
> > train, the same two lightning strikes, and there is only one pool of
> > water surrounding the embankment and the open train cars. So you tell
> > me, how can the water be stationary relative to the train AND
> > stationary relative to the embankment?
>
> It's the same two lightning strikes, but it is occurring at A on the
> embankment and A' on the train.
So?
>
> You can have a bucket of water that is stationary on the embankment
> and a bucket of water that is stationary on the train.
Same body of water that the train is immersed in and the embankment is
immersed in.
If it's not the same body of water, then there has to be a boundary
between the two bodies of water. Where is that boundary?
That's just it. Whether they are simultaneous or not depends on the
signals they actually receive at their locations. That is, the
observers M and M' are not AT the locations A, A', B, B'. They are at
the places marked M and M'. What they know is what happens where they
are, and THAT tells them what happens at A, A', B, and B'. They have
no other way of knowing.
PD
Well, hold on a second. Why isn't it possible the water is stationary
relative to the train and not stationary relative to the embankment?
> then the light from the
> lightning strike at A and B will not reach the observer at M'
> simultaneously and neither will the light from the lightning strikes
> at A' and B'.
Right.
But the observer M' then says the following:
"OK, I know the following things:
1. The strikes happened at distances that are equally apart from me.
2. The speed of the signal from those two places traveling to me is
the same in both cases.
3. The signals did not arrive at the same time."
From these bits of information it is OBVIOUS that the strikes
originally happened at different times, because the time of
propagation of the signal from the strikes to where the observer is
standing is identical. If the time of propagation is the same, and
they arrived at different times, then they started at different times.
No escaping that conclusion.
mpc755
> On Oct 9, 11:01 am, mpc755 <mpc...@gmail.com> wrote:
>
>
>
> > On Oct 9, 11:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
>
> > car, which implies the water is stationary relative to the embankment
> > and not stationary relative to the train,
>
> Well, hold on a second. Why isn't it possible the water is stationary
> relative to the train and not stationary relative to the embankment?
>
The water could be stationary relative to the train and not stationary
relative to the embankment. In that case, the light from the lightning
strike at B/B' will travel from B' to M and the light from the
lightning strike at A/A' will travel from A' to M. The light from A'
and B' will reach M' simultaneously.
If the water is stationary relative to the train and not stationary
relative to the embankment, the lightning strikes at A and B are
irrelevant in terms of where the light travels from.
> > then the light from the
> > lightning strike at A and B will not reach the observer at M'
> > simultaneously and neither will the light from the lightning strikes
> > at A' and B'.
>
> Right.
>
> But the observer M' then says the following:
> "OK, I know the following things:
> 1. The strikes happened at distances that are equally apart from me.
> 2. The speed of the signal from those two places traveling to me is
> the same in both cases.
> 3. The signals did not arrive at the same time."
> From these bits of information it is OBVIOUS that the strikes
> originally happened at different times, because the time of
> propagation of the signal from the strikes to where the observer is
> standing is identical. If the time of propagation is the same, and
> they arrived at different times, then they started at different times.
> No escaping that conclusion.
It sounds as if we are back discussing the water being stationary
relative to the embankment. If that is the case then the observer at
M' will not conclude the light traveled from A' and B' to reach him.
If he does so, then he is incorrect. If the water is stationary
relative to the embankment the Observer at M' will correctly conclude
the light from the lightning strike at A/A' traveled from A and the
light from the lightning strike at B/B' traveled from B.
mpc755
> On Oct 9, 10:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > On Oct 9, 8:53 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > On Oct 9, 8:57 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > On Oct 8, 8:34 pm, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
>
> > light from A' and B' reaches M' simultaneously.
>
> A and A' are a single strike. B and B' are a single strike.
Yes, A and A' are a single strike but A and A' are two different
locations in three dimensional space. A in on the embankment and A' is
on the train.
> The light from A/A' travels through the *same medium* that the
> embankment and the open flatbed train cars are immersed in. The light
> from B/B' does the same thing.
> So how does the light, coming from a single lightning strike (A/A'),
> traveling through a common medium, arrive at the same observer M' both
> simultaneously and not simultaneously as the light from B/B'?
It doesn't. If the train contains open flatbed cars, then you are
implying the medium is stationary relative to the embankment. Meaning
the light travels from B to M' and from A to M'. The marks made by the
lightning strikes are A' and B' are meaningless in this scenario. Even
with the marks made at A' and B', since the medium is stationary
relative to the embankment, all of the light associated with the
lightning strikes travels from A to M' and from B to M'.
> The observer M' either sees the flashes from the strikes at his eyes at
> the same time or he doesn't. He can't do both.
>
Incorrect. If the medium is stationary relative to the embankment in
the embankment frame of reference and the medium is stationary
relative to the train in the train frame of reference the observer at
M' will see the light from the lightning strikes at A' and B'
simultaneously. The light from A and B will have to transition from
the embankment frame of reference to the train frame of reference and
will arrive at M' at different times.
>
>
> > > The train observer has to agree with that.
>
> > Yes, the train observer agrees the light from A and B reaches him at
> > different times, but the light from A' and B' reaches him
> > simultaneously.
>
> A and A' are ONE lightning strike. B and B' are ONE lightning strike.
>
Yes, they are one lightning strike but they occur at two different
locations. A on the embankment and A' on the train. Likewise for the
lightning strike at B/B'.
> Let's say that the ONE lightning strike at A/A' is greenish, and the
> lightning strike at B/B' is yellowish.
>
> The question is simple. There is a guy M' who is going to see the two
> lightning flashes. Does he see the yellowish and greenish ones at the
> same time or at different times? There can only be one answer, as this
> is something that the guy can write down when it happens.
>
If the medium is stationary relative to the train in the train frame
of reference and the medium is stationary relative to the embankment
in the embankment frame of reference the observer at M' is going to
see the yellowish light from A' and the greenish light from B' arrive
simultaneously. He will also see the yellowish light from A and the
greenish light from B arrive at different times.
If the medium is stationary relative to the train in all reference
frames, then the Observer at M' will see a single lighting strike from
A' and a single lightning strike at B' both arrive simultaneously.
If the medium is stationary relative to the embankment in all
reference frames, the Observer at M' will see a single lightning
strike from A and a single lightning strike at B arrive at different
times.
If the train contains open flatbed cars, then the water will be
stationary relative to the embankment and the light from the lightning
strikes at A/A' and B/B' will travel from A to M' and from B to M'.
If the train is enclosed and the water is moving with the train in the
train frame of reference and the water on the embankment is stationary
relative to the embankment, then it is the train that is the boundary.
>
>
> > Pebbles are dropped at A, A', B, and B' simultaneously as determined
> > by observers.
>
> That's just it. Whether they are simultaneous or not depends on the
> signals they actually receive at their locations. That is, the
> observers M and M' are not AT the locations A, A', B, B'. They are at
> the places marked M and M'. What they know is what happens where they
> are, and THAT tells them what happens at A, A', B, and B'. They have
> no other way of knowing.
There are observers at A, A', B and B' and they all have clickers and
they all click their clickers when the pebbles hit the water. It is
determined all four observers hit their clickers at the same time.
PD
> On Oct 9, 12:35 pm, PD <thedraperfam...@gmail.com> wrote:
>
>
>
> > On Oct 9, 11:01 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > On Oct 9, 11:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > I missed where you say it is an open train car. If it is an open train
> > > car, which implies the water is stationary relative to the embankment
> > > and not stationary relative to the train,
>
> > Well, hold on a second. Why isn't it possible the water is stationary
> > relative to the train and not stationary relative to the embankment?
>
> The water could be stationary relative to the train and not stationary
> relative to the embankment. In that case, the light from the lightning
> strike at B/B' will travel from B' to M and the light from the
> lightning strike at A/A' will travel from A' to M. The light from A'
> and B' will reach M' simultaneously.
And if this were so, then you'd be able to measure a different speed
of propagation of the signal someplace.
Remember that for BOTH observers M and M', the distance between the
strikes and where the observer is standing is identical. That is, A--M
= M--B, and A--M' = M'--B.
And so if the speed of the signal propagating from A to M and from B
to M is the same, then the time of propagation has to be the same.
So what the observer M SEES (simultaneous or not simultaneous)
determines completely whether the strikes are REALLY simultaneous or
not.
And the same statements hold true for M'.
And here is what is REALLY seen in experiment (or analogous
experiment): M sees the flashes at the same time and M' sees the
flashes at different times.
The only way this can be true is if the speed of propagation from A is
somehow different than the speed of propagation from B.
But measurements in REAL LIFE show that this isn't the case. The speed
is always the same.
I see that this simple gedanken continues to cause you problems and
you're having trouble understanding the point.
mpc755
> On Oct 9, 11:54 am, mpc755 <mpc...@gmail.com> wrote:
>
>
>
> > On Oct 9, 12:35 pm, PD <thedraperfam...@gmail.com> wrote:
>
> > > On Oct 9, 11:01 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > On Oct 9, 11:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > > I missed where you say it is an open train car. If it is an open train
> > > > car, which implies the water is stationary relative to the embankment
> > > > and not stationary relative to the train,
>
> > > Well, hold on a second. Why isn't it possible the water is stationary
> > > relative to the train and not stationary relative to the embankment?
>
> > The water could be stationary relative to the train and not stationary
> > relative to the embankment. In that case, the light from the lightning
> > strike at B/B' will travel from B' to M and the light from the
> > lightning strike at A/A' will travel from A' to M. The light from A'
> > and B' will reach M' simultaneously.
>
> And if this were so, then you'd be able to measure a different speed
> of propagation of the signal someplace.
>
> Remember that for BOTH observers M and M', the distance between the
> strikes and where the observer is standing is identical. That is, A--M
> = M--B, and A--M' = M'--B.
Correct, at the time of the lightning strikes.
> And so if the speed of the signal propagating from A to M and from B
> to M is the same, then the time of propagation has to be the same.
> So what the observer M SEES (simultaneous or not simultaneous)
> determines completely whether the strikes are REALLY simultaneous or
> not.
> And the same statements hold true for M'.
>
Correct, for M' and the lightning strikes at A' and B'.
> And here is what is REALLY seen in experiment (or analogous
> experiment): M sees the flashes at the same time and M' sees the
> flashes at different times.
>
M sees the flashes at the same time if the medium is stationary
relative to him.
M' sees the flashes at different times from A and B because the light
has traveled different distances from A and B to M'. M' is moving
relative to A and B.
> The only way this can be true is if the speed of propagation from A is
> somehow different than the speed of propagation from B.
>
Incorrect. M' sees the light from B prior to the light from A because
M' is hastening towards B and away from A.
> But measurements in REAL LIFE show that this isn't the case. The speed
> is always the same.
>
Yes, the speed of light is always 'c'. But what you do not understand
is where the light emanates from is dependent on the relative motion
of the medium it was created in and is traveling through. See Fizeau
experiment (http://en.wikipedia.org/wiki/Fizeau_experiment)
PD
> On Oct 9, 12:30 pm, PD <thedraperfam...@gmail.com> wrote:
>
>
>
> > On Oct 9, 10:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > On Oct 9, 8:53 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > On Oct 9, 8:57 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > On Oct 8, 8:34 pm, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > Yes, the light from A and B reaches M' at different times, but the
> > > light from A' and B' reaches M' simultaneously.
>
> > A and A' are a single strike. B and B' are a single strike.
>
> Yes, A and A' are a single strike but A and A' are two different
> locations in three dimensional space. A in on the embankment and A' is
> on the train.
No, they are not. You have not read the gedanken carefully. A lighting
strike hits in ONE place, not two. A and A' are two labels for the
same point. In the original gedanken, A and A' label the point where
the train meets the track at one end of the train. That is ONE POINT.
Please reread it and pay more attention than what you have been doing
so far.
>
> > The light from A/A' travels through the *same medium* that the
> > embankment and the open flatbed train cars are immersed in. The light
> > from B/B' does the same thing.
> > So how does the light, coming from a single lightning strike (A/A'),
> > traveling through a common medium, arrive at the same observer M' both
> > simultaneously and not simultaneously as the light from B/B'?
>
> It doesn't. If the train contains open flatbed cars, then you are
> implying the medium is stationary relative to the embankment.
No, I'm not. There's no such implication at all. What you know is true
is that there is ONE medium, not two.
OK, and this is where you get a little loony.
You say that the observer M' will see the green flash and the yellow
flash at the same time AND not at the same time?
This kind of odd behavior you describe has never been observed in
experiment.
There is no enclosure implied in the gedanken. Please reread it
carefully.
>
>
>
> > > Pebbles are dropped at A, A', B, and B' simultaneously as determined
> > > by observers.
>
> > That's just it. Whether they are simultaneous or not depends on the
> > signals they actually receive at their locations. That is, the
> > observers M and M' are not AT the locations A, A', B, B'. They are at
> > the places marked M and M'. What they know is what happens where they
> > are, and THAT tells them what happens at A, A', B, and B'. They have
> > no other way of knowing.
>
> There are observers at A, A', B and B' and they all have clickers and
> they all click their clickers when the pebbles hit the water. It is
> determined all four observers hit their clickers at the same time.
How is it determined that they hit their clickers at the same time?
What procedure would you need to ensure that?
I want you to think about this very carefully...
PD
> On Oct 9, 1:11 pm, PD <thedraperfam...@gmail.com> wrote:
>
>
>
> > On Oct 9, 11:54 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > On Oct 9, 12:35 pm, PD <thedraperfam...@gmail.com> wrote:
>
> > > > On Oct 9, 11:01 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > On Oct 9, 11:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > > > I missed where you say it is an open train car. If it is an open train
> > > > > car, which implies the water is stationary relative to the embankment
> > > > > and not stationary relative to the train,
>
> > > > Well, hold on a second. Why isn't it possible the water is stationary
> > > > relative to the train and not stationary relative to the embankment?
>
> > > The water could be stationary relative to the train and not stationary
> > > relative to the embankment. In that case, the light from the lightning
> > > strike at B/B' will travel from B' to M and the light from the
> > > lightning strike at A/A' will travel from A' to M. The light from A'
> > > and B' will reach M' simultaneously.
>
> > And if this were so, then you'd be able to measure a different speed
> > of propagation of the signal someplace.
>
> > Remember that for BOTH observers M and M', the distance between the
> > strikes and where the observer is standing is identical. That is, A--M
> > = M--B, and A--M' = M'--B.
>
> Correct, at the time of the lightning strikes.
Or any time. The track observer could do it all afterwards if he
wanted to. He just marks the location where he was standing and then
goes to look for the scorch mark on the track and he measures the
distance from where he was standing to the scorch mark. Then he does
the same for the other scorch mark.
The train observer can do the same thing.
>
> > And so if the speed of the signal propagating from A to M and from B
> > to M is the same, then the time of propagation has to be the same.
> > So what the observer M SEES (simultaneous or not simultaneous)
> > determines completely whether the strikes are REALLY simultaneous or
> > not.
> > And the same statements hold true for M'.
>
> Correct, for M' and the lightning strikes at A' and B'.
A' and B' happen at the same locations as A and B. A and A' are two
different labels applied to the same point. Same for B and B'.
>
> > And here is what is REALLY seen in experiment (or analogous
> > experiment): M sees the flashes at the same time and M' sees the
> > flashes at different times.
>
> M sees the flashes at the same time if the medium is stationary
> relative to him.
>
> M' sees the flashes at different times from A and B because the light
> has traveled different distances from A and B to M'. M' is moving
> relative to A and B.
M' cannot see the flashes at the same time AND at different times. It
has to be one or the other. There is only one green flash and he will
see it only once, and there is only one yellow flash and he will see
it only once. When he sees the green and yellow flashes, does he see
them at the same time or at different times? He doesn't see the green
flash twice or the yellow flash twice.
mpc755
> On Oct 9, 12:08 pm, mpc755 <mpc...@gmail.com> wrote:
>
>
>
> > On Oct 9, 12:30 pm, PD <thedraperfam...@gmail.com> wrote:
>
> > > On Oct 9, 10:06 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > On Oct 9, 8:53 am, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > On Oct 9, 8:57 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > > > > > On Oct 8, 8:34 pm, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > > Yes, the light from A and B reaches M' at different times, but the
> > > > light from A' and B' reaches M' simultaneously.
>
> > > A and A' are a single strike. B and B' are a single strike.
>
> > Yes, A and A' are a single strike but A and A' are two different
> > locations in three dimensional space. A in on the embankment and A' is
> > on the train.
>
> No, they are not. You have not read the gedanken carefully. A lighting
> strike hits in ONE place, not two. A and A' are two labels for the
> same point. In the original gedanken, A and A' label the point where
> the train meets the track at one end of the train. That is ONE POINT.
>
> Please reread it and pay more attention than what you have been doing
> so far.
>
The lightning strike leaves marks at A, A', B, and B'. This is four
different locations in three dimensional space. A and A' and B and B'
were co-located at the time of the strikes, but they are four
different locations.
If A and A' are two labels for the same point, why does the Observer
at M measure to A and B and the Observer at M' measure to A' and B'?
The measure to the appropriate marks because there are four marks.
Please try and understand if you have four marks at four locations
that is four points.
>
>
> > > The light from A/A' travels through the *same medium* that the
> > > embankment and the open flatbed train cars are immersed in. The light
> > > from B/B' does the same thing.
> > > So how does the light, coming from a single lightning strike (A/A'),
> > > traveling through a common medium, arrive at the same observer M' both
> > > simultaneously and not simultaneously as the light from B/B'?
>
> > It doesn't. If the train contains open flatbed cars, then you are
> > implying the medium is stationary relative to the embankment.
>
> No, I'm not. There's no such implication at all. What you know is true
> is that there is ONE medium, not two.
>
If there is one medium that is stationary relative to one of the
frames of reference in Einstein's train thought experiment then that
means it is moving relative to the other frame of reference which
means there is a preferred frame of reference.
Yes, because the medium is stationary relative to the embankment in
the embankment frame of reference and the medium is stationary
relative to the train in the train frame of reference. Therefore, the
light from the lightning strikes on the train travel from A' and B' to
M' and the light from the lightning strikes on the embankment travel
from A and B to M'.
There is no enclosure implied in Einstein's train thought experiment
because he did not realize the mistake he was making. Einstein states
the speed of light is 'c' regardless of the speed of the source. What
Einstein failed to realize is the speed of light is 'c' relative to
the medium it is propagating through:
'Fizeau experiment'
http://en.wikipedia.org/wiki/Fizeau_experiment
>
>
>
>
> > > > Pebbles are dropped at A, A', B, and B' simultaneously as determined
> > > > by observers.
>
> > > That's just it. Whether they are simultaneous or not depends on the
> > > signals they actually receive at their locations. That is, the
> > > observers M and M' are not AT the locations A, A', B, B'. They are at
> > > the places marked M and M'. What they know is what happens where they
> > > are, and THAT tells them what happens at A, A', B, and B'. They have
> > > no other way of knowing.
>
> > There are observers at A, A', B and B' and they all have clickers and
> > they all click their clickers when the pebbles hit the water. It is
> > determined all four observers hit their clickers at the same time.
>
> How is it determined that they hit their clickers at the same time?
> What procedure would you need to ensure that?
> I want you to think about this very carefully...
There are observer as close to each contact point between the pebble
and the water as possible. The length of wire from the clicker to the
clicker response unit is the same for all observers. If the clicks are
determined to be simultaneous at the clicker response unit, then the
pebbles each hit the water simultaneously.
mpc755
Yes, for the scorch marks in their frame of reference. The light from
the other frame of reference travels different distances to them.
>
>
> > > And so if the speed of the signal propagating from A to M and from B
> > > to M is the same, then the time of propagation has to be the same.
> > > So what the observer M SEES (simultaneous or not simultaneous)
> > > determines completely whether the strikes are REALLY simultaneous or
> > > not.
> > > And the same statements hold true for M'.
>
> > Correct, for M' and the lightning strikes at A' and B'.
>
> A' and B' happen at the same locations as A and B. A and A' are two
> different labels applied to the same point. Same for B and B'.
>
If they are the same point, then why are there four marks?
>
>
> > > And here is what is REALLY seen in experiment (or analogous
> > > experiment): M sees the flashes at the same time and M' sees the
> > > flashes at different times.
>
> > M sees the flashes at the same time if the medium is stationary
> > relative to him.
>
> > M' sees the flashes at different times from A and B because the light
> > has traveled different distances from A and B to M'. M' is moving
> > relative to A and B.
>
> M' cannot see the flashes at the same time AND at different times. It
> has to be one or the other. There is only one green flash and he will
> see it only once, and there is only one yellow flash and he will see
> it only once. When he sees the green and yellow flashes, does he see
> them at the same time or at different times? He doesn't see the green
> flash twice or the yellow flash twice.
>
Take another look at the animation and you can see how M' sees the
flashes from A' and B' at the same time and the flashes from A and B
at different times:
http://www.youtube.com/watch?v=jyWTaXMElUk
papa...@gmail.com
> On Oct 9, 1:17 pm, PD <thedraperfam...@gmail.com> wrote:
>
> > There is no enclosure implied in the gedanken. Please reread it
> > carefully.
>
> There is no enclosure implied in Einstein's train thought experiment
> because he did not realize the mistake he was making. Einstein states
> the speed of light is 'c' regardless of the speed of the source. What
> Einstein failed to realize is the speed of light is 'c' relative to
> the medium it is propagating through:
That is, of course, totally wrong. Einstein clearly wrote in his 1905
paper:
"...In agreement with experience we further assume the quantity 2AB/
(t'_A-t_A)=c to be a universal constant—the velocity of light in empty
space."
So the train gedanken, which was a pedagogical example for people like
you, is clearly setup in deep space and far away from any
gravitational mass.
The two events could be two nuclear blasts, observer M just floating
in space on a small ship and observer M' moving at a speed v in a
small ship.
So all your Aether nonsense is totally useless in this example.
Einstein himself also clearly wrote about it:
"The introduction of a “luminiferous ether” will prove to be
superfluous inasmuch as the view here to be developed will not require
an “absolutely stationary space” provided with special properties, nor
assign a velocity-vector to a point of the empty space in which
electromagnetic processes take place."
Miguel Rios
PD
A and A' are colocated but they are two different locations? Listen to
yourself! LOL!
Lightning strikes at ONE POINT at the end of the train, where one end
of the train meets the track. There is a scorch mark left on the track
(A) and a scorch mark left on the train (A') where this ONE spot
occurred.
Another lightning bolt strikes at ONE point at the other end of the
train, where that end of the train meets the track.
Here's another way you can think of it.
Set up a graph with an x and y axis. The x and y axis meet at ONE
POINT. That point is labeled (y=0) for the y-axis and is labeled (x=0)
for the x-axis. Does the fact that there are two labels mean that it
is ONE point or TWO points where the axes meet?
>
> If A and A' are two labels for the same point, why does the Observer
> at M measure to A and B and the Observer at M' measure to A' and B'?
> The measure to the appropriate marks because there are four marks.
I'm sorry, but you are REALLY poor at reading comprehension. Try
reading it again.
>
> Please try and understand if you have four marks at four locations
> that is four points.
>
>
>
> > > > The light from A/A' travels through the *same medium* that the
> > > > embankment and the open flatbed train cars are immersed in. The light
> > > > from B/B' does the same thing.
> > > > So how does the light, coming from a single lightning strike (A/A'),
> > > > traveling through a common medium, arrive at the same observer M' both
> > > > simultaneously and not simultaneously as the light from B/B'?
>
> > > It doesn't. If the train contains open flatbed cars, then you are
> > > implying the medium is stationary relative to the embankment.
>
> > No, I'm not. There's no such implication at all. What you know is true
> > is that there is ONE medium, not two.
>
> If there is one medium that is stationary relative to one of the
> frames of reference in Einstein's train thought experiment then that
> means it is moving relative to the other frame of reference which
> means there is a preferred frame of reference.
If there is a medium, yes.
But there isn't a preferred frame of reference, is there?
And how do you know that if there is a medium then it is stationary
with respect to the embankment and not with respect to the train? What
if it's not stationary with respect to either one?
Woah! The same medium is stationary with respect to the train in one
reference frame and stationary with respect to the embankment in the
other reference frame?
It's ONE medium being looked at from two different reference frames at
the same time? How can anything do that?
If you had a bird, a car, and a street sign, could you explain how the
bird could be moving along with the car from the street sign's frame
of reference, and moving along with the street sign from the car's
frame of reference???? LOL!
LOL!
So what if we do the experiment where there is no isolation of the
medium into two chunks?
PD
>
> > > > That's just it. Whether they are simultaneous or not depends on the
> > > > signals they actually receive at their locations. That is, the
> > > > observers M and M' are not AT the locations A, A', B, B'. They are at
> > > > the places marked M and M'. What they know is what happens where they
> > > > are, and THAT tells them what happens at A, A', B, and B'. They have
> > > > no other way of knowing.
>
> > > There are observers at A, A', B and B' and they all have clickers and
> > > they all click their clickers when the pebbles hit the water. It is
> > > determined all four observers hit their clickers at the same time.
>
> > How is it determined that they hit their clickers at the same time?
> > What procedure would you need to ensure that?
> > I want you to think about this very carefully...
>
> There are observer as close to each contact point between the pebble
> and the water as possible. The length of wire from the clicker to the
> clicker response unit is the same for all observers.
And the speed of the signal is the same through the wire in both
cases.
So if the speed in the wire is the same, and the length of the wire is
the same, then you know that the time propagation through the wires
would be the same, right?
And if this is the case, then you know the following:
1. If the clicker response unit records signals from the clickers at
the same time, THEN you know that the pebbles landed at the same time.
2. If the clicker response unit records signals from the clickers at
different times, THEN you know that the pebbles landed at different
times.
Right? This is how you determine from the clicker and clicker response
system whether the pebbles really landed at the same time or not.
OK, so here's the situation with the lightning strikes:
You've got ONE lightning strike at one end of the train, and ONE
lightning strike at the other end of the train.
The path length (just like the wire length) from one lightning strike
to the observer M is the same as the path length from the other
lightning strike to the observer M. Equal path lengths, just like
equal wire lengths.
The path length (just like the wire length) from one lightning strike
to the observer M' is the same as the path length from the other
lightning strike to the observer M'. Equal path lengths, just like
equal wire lengths.
And you know the speed of the signal from one lightning strike to M is
the same as the speed of the signal from the other lightning strike to
M.
And you know the speed of the signal from one lightning strike to M'
is the same as the speed of the signal from the other lightning strike
to M'.
The problem is, in experiment, M says he received the signals at the
same time (clicker case (1)), and M' says he received the signals at
different times (clicker case (2)).
mpc755
Yes, and Einstein was mistaken. His whole concept of curved space-time
is simply displaced aether.
mpc755
Yes, two points where the embankment and the train meet at A/A' and
two points where the embankment and the train meet at B/B'.
There is a mark on the train and a mark on the embankment where the
lightning strike occurs at A/A' and there is a mark on the train and
on the embankment where the lightning strike occurs at B/B'.
Do you understand there is a mark at A on the embankment and A' on the
train? Do you understand that one of these points in on the embankment
and one of these points is on the train?
The point on the embankment is in the embankment reference frame and
the aether is stationary on the embankment in the embankment reference
frame. The point on the train is in the train reference frame and the
aether is stationary on the train in the train reference frame.
Just as you can have a mark at A on the embankment and A' on the train
you can have stationary aether on the embankment and stationary aether
on the train.
mpc755
Just like there are four observers at A, A', B, and B' the lightning
strikes occur at 4 points. When the light from the lightning strikes
reach M and M' are dependent on the medium the light travels through.
PD
Where the x and y axis meet on a graph, (y=0) marks that place on the
y-axis and (x=0) marks that place on the x-axis. Is that one location
or two?
LOL!!
>
> The point on the embankment is in the embankment reference frame and
> the aether is stationary on the embankment in the embankment reference
> frame. The point on the train is in the train reference frame and the
> aether is stationary on the train in the train reference frame.
>
> Just as you can have a mark at A on the embankment and A' on the train
> you can have stationary aether on the embankment and stationary aether
> on the train.
Lovely! You're so fun!
So we have ONE aether and it is stationary relative to the embankment
and stationary relative to the train at the same time!
Tell me, can you do that with one ball, too?
LOL!!
PD
There aren't four observers at A, A', B and B'.
Read it again!
> the lightning
> strikes occur at 4 points.
Wow! One lightning strike strikes in two places at once!
LOL!!
> When the light from the lightning strikes
> reach M and M' are dependent on the medium the light travels through.
Especially when it's ONE medium!
You're a hoot, you are!
mpc755
How many marks are there?
Two on the train and two on the embankment.
Two marks are on the train where the aether is stationary relative to
the train frame of reference. Two marks are on the embankment where
the aether is stationary relative to the embankment frame of
reference.
>
>
> > The point on the embankment is in the embankment reference frame and
> > the aether is stationary on the embankment in the embankment reference
> > frame. The point on the train is in the train reference frame and the
> > aether is stationary on the train in the train reference frame.
>
> > Just as you can have a mark at A on the embankment and A' on the train
> > you can have stationary aether on the embankment and stationary aether
> > on the train.
>
> Lovely! You're so fun!
> So we have ONE aether and it is stationary relative to the embankment
> and stationary relative to the train at the same time!
> Tell me, can you do that with one ball, too?
>
> LOL!!
If the embankment is knee deep in water, the water will be stationary
in the embankment frame of reference. If the train is knee deep in
water, where the train is enclosed, the water will be stationary in
the train frame of reference.
Replace one medium with another. Replace water with aether.
mpc755
You asked me how the pebbles dropped at A, A', B, and B' could be
determined to be simultaneous and I explained how with four observers,
one at each pebble drop.
> > the lightning
> > strikes occur at 4 points.
>
> Wow! One lightning strike strikes in two places at once!
> LOL!!
>
Yes. When it leaves a mark on the train and on the embankment. This is
two different places.
> > When the light from the lightning strikes
> > reach M and M' are dependent on the medium the light travels through.
>
> Especially when it's ONE medium!
>
> You're a hoot, you are!
>
Water is one medium, but if it is on the train and stationary relative
to the train and water is on the embankment stationary relative to the
embankment, pebbles dropped at A, A', B, and B' will have their
associated waves from A and B reach M and from A' and B' reach M'
simultaneously.
>
>
mpc755
Let's see if we can find any common ground. Forget Einstein's Train
Thought Experiment for a second.
We have an embankment that is knee deep in water. The water on the
embankment is stationary relative to the embankment. We have an
enclosed train that is need deep in water. The water on the train is
stationary relative to the train.
Four pebbles are dropped at A and B on the embankment and A' and B' on
the train. A and B are equi-distant from M and A' and B' are equi-
distant from M'. The distance from A and B to M is the same distance
as A' and B' are to M'.
The pebbles are dropped simultaneously at A and A'.
The pebbles are dropped simultaneously at B and B'.
If the waves from A and B reach M simultaneously, then the waves from
A' and B' reach M' simultaneously.
papa...@gmail.com
Well obviously the whole scientific community considers that Einstein
was right and that you are....... not even wrong!!
Well I let you talking to yourself again....
Miguel Rios
PD
Answer this question, MPC! The answer is obvious to a 4th grader!
>
> > LOL!!
>
> How many marks are there?
>
> Two on the train and two on the embankment.
Right, and there are two marks for the place where the x-axis meets
the y-axis.
Are you an idiot? Why yes, I believe you are trying really hard to be
one!
>
> Two marks are on the train where the aether is stationary relative to
> the train frame of reference. Two marks are on the embankment where
> the aether is stationary relative to the embankment frame of
> reference.
>
>
>
>
>
> > > The point on the embankment is in the embankment reference frame and
> > > the aether is stationary on the embankment in the embankment reference
> > > frame. The point on the train is in the train reference frame and the
> > > aether is stationary on the train in the train reference frame.
>
> > > Just as you can have a mark at A on the embankment and A' on the train
> > > you can have stationary aether on the embankment and stationary aether
> > > on the train.
>
> > Lovely! You're so fun!
> > So we have ONE aether and it is stationary relative to the embankment
> > and stationary relative to the train at the same time!
> > Tell me, can you do that with one ball, too?
>
> > LOL!!
>
> If the embankment is knee deep in water, the water will be stationary
> in the embankment frame of reference.
Why? Why isn't it flowing with the train?
> If the train is knee deep in
> water, where the train is enclosed,
Who said the train is enclosed? Are we repeating ourselves now?
PD
That's fine, but you can also do with the two observers M and M' just
as we described. That's all we need.
And I've told you what is experimentally observed.
>
> > > the lightning
> > > strikes occur at 4 points.
>
> > Wow! One lightning strike strikes in two places at once!
> > LOL!!
>
> Yes. When it leaves a mark on the train and on the embankment. This is
> two different places.
LOL! You are a goofball of large proportions indeed.
You can't see that a lightning bolt that strikes at the ONE place
where the train and the track meet will leave a mark on both?
Do you not even understand what you are reading when you read
Einstein's gedanken?
>
> > > When the light from the lightning strikes
> > > reach M and M' are dependent on the medium the light travels through.
>
> > Especially when it's ONE medium!
>
> > You're a hoot, you are!
>
> Water is one medium, but if it is on the train and stationary relative
> to the train and water is on the embankment stationary relative to the
> embankment,
Now, now. How can ONE body of water be stationary relative both to the
embankment and the train?
Is a lake stationary relative to both the boat and to the shore?
Really, are you TRYING to look stupid?
PD
Nah, that's was the whole point. You were trying to explain what
relativity says would happen in the train gedanken and what you say
would happen instead.
Now you don't want to talk about the train gedanken at all, not to
mention what's measured in real experiments that are related to it,
using real light.
mpc755
I'm just pointing out to you what happens if the medium the wave
travels through on the embankment is stationary relative to the
embankment and the medium the wave travels through on the train is
stationary relative to the train. It's an analogy.
And if you then take the analogy of a pebble in water and you modify
the analogy to be light traveling through water you will come to the
same conclusion.
If the light waves from A and B reach M simultaneously then the light
waves from A' and B' reach M' simultaneously.
You then change the medium to be aether instead of water and the same
conclusion holds true.
If the light waves from A and B reach M simultaneously then the light
PD
As I said in the beginning, the train gedanken was designed to explain
relativity to people who have a hard time understanding it. It makes a
certain class of predictions that can be tested in equivalent
experiments. Those predictions match what is actually observed.
You have a scenario that has nothing to do with the train gedanken,
involving two tanks of water slipping past each other with pebbles
dropped in them in four different places. This doesn't make any
predictions, as far as I can tell, about what would be measured with
light. If you think it does, and it makes predictions other than what
relativity says, then I'm afraid the experiments have already ruled
your model out.
PD
PD
> If the aether is stationary relative to the embankment and stationary
> relative to the train, this is what will occur in Einstein's train
> thought experiment:
>
> http://www.youtube.com/watch?v=jyWTaXMElUk
I think the end result of this discussion, MPC, is that you've never
understood what's being said in the Einstein train gedanken.
At this point, it might have been effective for you to say, "I guess I
don't understand what Einstein was trying to say. Is there anyone that
is willing to walk through it with me to explain to me what it's
saying?"
For some people this is emotionally difficult to do. One recourse for
such people is to pretend that they understand what they do not, and
to try to invent something they can at least call their own, because
they do understand what they invent for themselves. The problem is,
this has nothing to do with science, where the value of an idea is
determined by how nature really acts, not how intuitive it is in our
heads.
The right steps are to ask the following:
1. "What is this relativity theory, exactly, and what does it say?"
2. "OK, now that I understand what it claims, what makes you think
it's right?"
3. "If there are other claims that have been put forward that are
different, how do you know that any of those are not right?"
PD
Bruce Richmond
> On Oct 9, 8:53 am, mpc755 <mpc...@gmail.com> wrote:
>
>
>
>
>
> > On Oct 9, 8:57 am, PD <thedraperfam...@gmail.com> wrote:
>
> > > On Oct 8, 8:34 pm, mpc755 <mpc...@gmail.com> wrote:
>
> > > > > > > > > > > > > Sorry, I've fouled this up.
>
> > > > > > > > > > > > > light from B/B' arrive simultaneously at M and NOT simultaneously at
> > > > > > > > > > > > > M'.
>
> > > > > > > > > > > > > And if this were viewed from M', because the propagation toward M' is
> > > > > > > > > > > > > c from either A/A' or B/B', then it would be clear that events at A
> > > > > > > > > > > > > and B were not simultaneous.
>
> > > > > > > > > > > > > PD
>
> > > > > > > > > > > > OK, at least you now understand Relativity of Simultaneity.
>
> > > > > > > > > > > > In Simultaneity of Relativity, both frames are equal.
>
> > > > > > > > > > > That's all well and good, but experiment agrees with Einstein, not
> > > > > > > > > > > with your picture.
>
> > > > > > > > > > How would you know? You just figured out what Relativity of
> > > > > > > > > > Simultaneity is two minutes ago.
>
> > > > > > > > > :>)
> > > > > > > > > Well, I certainly did have difficulty explaining it right at first.
>
> > > > > > > > > But the experimental stuff has been figured out a long time ago.
>
> > > > > > > > > > > > Consider the
> > > > > > > > > > > > aether to be 'entrained' by the embankment in the embankment frame of
> > > > > > > > > > > > reference and for the aether to be 'entrained' by the train in the
> > > > > > > > > > > > train frame of reference.
>
> > > > > > > > > > > OK, but the train observer could well be sitting on top of the train
> > > > > > > > > > > out in the open air, right along with the air that is surrounding the
> > > > > > > > > > > embankment.
> > > > > > > > > > > So unless you've got overlapping aethers, one passing through the
> > > > > > > > > > > other, then there would have to be a boundary between the two moving
> > > > > > > > > > > masses of aether, where they are rubbing up against each other. And in
> > > > > > > > > > > that case, there would be a region of aether in between where it is
> > > > > > > > > > > moving somewhat in between what the two entrained aethers are moving.
> > > > > > > > > > > And then just by moving, say, the embankment observer a little closer
> > > > > > > > > > > to the train, or the train observer a little to one side, then you'd
> > > > > > > > > > > start seeing the effect of the aether moving at a speed somewhat in
> > > > > > > > > > > between. However, this is not observed in equivalent experiments.
>
> > > > > > > > > > Post a link to the experiments you are referring to.
>
> > > > > > > > > Google "experimental basis for relativity"
>
> > > > > > > > If you say this is not observed in equivalent experiments, you should
> > > > > > > > be willing and able to backup up such a statement with specifics.
>
> > > > > > > > But, since you just figured out what Relativity of Simultaneity is
> > > > > > > > five minutes ago, its understandable you can't backup the claims you
> > > > > > > > make.
>
> > > > > > > Such cheesy baiting.
> > > > > > > If you actually do the search I recommended, and you click on the
> > > > > > > FIRST link it returns, you'll have a lovely list of experiments.
> > > > > > > If you cannot do even this without whining, is it an indicator that
> > > > > > > you are hopelessly lazy or hopelessly incompetent?
>
> > > > > > > > > > > This is what I mean by following the implications of an idea all the
> > > > > > > > > > > way through to look for *uniquely distinguishing* predictions. I've
> > > > > > > > > > > just given an example of a clear implication of AD, one that would be
> > > > > > > > > > > testable. And unfortunately, it doesn't match experiment. So it's
> > > > > > > > > > > gotta be wrong.
>
> > > > > > > > > > Experiments like de Sitter and the double star?
>
> > > > > > > > > No. That has to do with something else entirely.
> > > > > > > > > That has to do with a test that distinguishes ballistic emission
> > > > > > > > > theory and relativity.
> > > > > > > > > Nothing to do with simultaneity.
>
> > > > > > > > Simultaneity of Relativity is emission theory in an entrained aether.
>
> > > > > > > No, it's not. In your theory the speed of light is relative to the
> > > > > > > aether. In ballistic theory it is relative to the source.
>
> > > > > > If the train is half full of water and the water is stationary in the
> > > > > > train and you drop pebbles at A' and B', the waves from A' and B' will
> > > > > > reach M' simultaneously.
>
> > > > > > If the embankment is half full of water and the water is stationary
> > > > > > relative to the embankment and you drop pebbles into the water at A
> > > > > > and B, the waves from A and B will reach M simultaneously.
>
> > > > > > If you drop pebbles into the water at A and A' simultaneously and drop
> > > > > > pebbles into B and B' simultaneously, if the waves from A and B reach
> > > > > > M simultaneously, the waves from A' and B' will reach M'
> > > > > > simultaneously.
>
> > > > > If it helps, MPC, Einstein's train gedanken can just as well take
> > > > > place on open, flat-bed cars.
>
> > > > The water is stationary relative to the embankment and the train is
> > > > moving along under the water and not affecting the water. Pebbles are
> > > > dropped at A/A' and B/B'. The wave from B/B' travels from B to M'. The
> > > > waves from A and B and reach M simultaneously. The wave from A reaches
> > > > M'.
>
> > > And notice that the waves from A and B do not arrive at M' at the same
> > > time.
>
> > Yes, because the water is stationary relative to the embankment. In
> > this scenario, the embankment is the preferred frame.
>
> > For Einstein's train thought experiment to be truly relative, there
> > can be no preferred frame.
>
> > Therefore, the water must be stationary relative to the embankment in
> > the embankment frame of reference and stationary relative to the train
> > in the train reference frame.
>
> you have to satisfy both criteria at the same time!
>
> Here's where the fun starts. So if there is an aether (or water as you
> want to analogize), it has to be stationary with respect to the
> embankment AND to the train, at the same time. Not different
> scenarios. At the same time.
>
Why not use the LET interpertation for the same math. The aether/
water is not at rest with either the train or the embankment. But
because of the method used to sync clocks in each frame they both
measure the wave speed to be the same.
>
> > In this scenario, my animation holds in the light from A and B reaches
> > M and the light from A' and B' reaches M' simultaneously.
>
> No, certainly not. Because it's the same medium.
> The embankment observer notes that the light from A and B reaches M'
> at different times.
> The train observer has to agree with that. Nature doesn't produce two
> different measurable outcomes at the same time. There is only one.
> Either the light arrives at the same time at M' or it doesn't. The
> embankment observer and the train observer have to agree which one of
> those two it was.
>
> It appears that you are having a slow time getting a grip on what the
> Einstein gedanken really says.
>
>
>
> > > > The water is stationary relative to the train. Pebbles are dropped at
> > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > > > reach M' simultaneously. The wave from B' reaches M. A and B are
> > > > irrelevant in this scenario.
>
> > > OK, but there are really only two lightning strikes, and the water
> > > doesn't really have time to switch from being stationary relative to
> > > the embankment to being stationary relative to the train.
>
> > The water doesn't have to switch. The water is stationary relative to
> > the embankment in the embankment frame of reference and the water is
> > stationary relative to the train in the train frame of reference.
>
> But these aren't two different sequences of events. It's the same
> train, the same two lightning strikes, and there is only one pool of
> water surrounding the embankment and the open train cars. So you tell
> me, how can the water be stationary relative to the train AND
> stationary relative to the embankment?
>
>
>
> > There is a single lightning strike at A/A' but A in on the embankment
> > and A' is on the train. Likewise with the lightning strike at B/B'.
>
> > > Einstein's gedanken is about ONE pair of events (the lightning
> > > strikes) and what happens to the light as observed by M and M' for
> > > that ONE case, not two cases.
>
> > That is why I am saying Einstein is incorrect. He is trying to have it
> > both ways. He wants to have a single lightning strike in two reference
> > frames where the reference frames are not equal.
>
> What do you mean "equal"?
>
> The same sequence of events live in a bunch of reference frames all at
> once.
> If a sailor falls from the crow's nest of a ship, you can look at that
> sequence of events from the deck of the ship or you can look at that
> SAME sequence of events from the shore. This is looking at the SAME
> sequence of events from two different reference frames.
> In the reference frame of the ship, the sailor falls in a straight
> line down and lands at the bottom of the mast. In the reference frame
> of the shore (because the ship is moving relative to the shore), the
> sailor falls in a parabola, landing some distance to one side of where
> he left the crow's nest. This is what Galileo understood and used as
> an example to explain.
> There is only one sailor and he only fell once. The sailor travels in
> a straight line AND in a parabola AT THE SAME TIME. It's just that the
> path is dependent on the reference frame.
>
>
>
> > If his train thought experiment was correct with equal reference
> > frames, the light from the lightning strikes at A and B would reach M
> > and the light from the lightning strikes at A' and B' would reach M'
> > simultaneously:
>
> But they DON'T, in real life, as determined in experiment.
>
>
>
>
>
> >http://www.youtube.com/watch?v=jyWTaXMElUk
>
> > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -
Bruce Richmond
> > > M and the light from A' and B' reaches M' simultaneously.
>
> > No, certainly not. Because it's the same medium.
> > The embankment observer notes that the light from A and B reaches M'
> > at different times.
>
> light from A' and B' reaches M' simultaneously.
There is only one wave front emitted at A/A' and one at B/B'. Your
inimation is wrong.
> > The train observer has to agree with that.
>
> Yes, the train observer agrees the light from A and B reaches him at
> different times, but the light from A' and B' reaches him
> simultaneously.
>
>
>
>
>
> > Nature doesn't produce two
> > different measurable outcomes at the same time. There is only one.
> > Either the light arrives at the same time at M' or it doesn't. The
> > embankment observer and the train observer have to agree which one of
> > those two it was.
>
> > It appears that you are having a slow time getting a grip on what the
> > Einstein gedanken really says.
>
> > > > > The water is stationary relative to the train. Pebbles are dropped at
> > > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B'
> > > > > reach M' simultaneously. The wave from B' reaches M. A and B are
> > > > > irrelevant in this scenario.
>
> > > > OK, but there are really only two lightning strikes, and the water
> > > > doesn't really have time to switch from being stationary relative to
> > > > the embankment to being stationary relative to the train.
>
> > > The water doesn't have to switch. The water is stationary relative to
> > > the embankment in the embankment frame of reference and the water is
> > > stationary relative to the train in the train frame of reference.
>
> > But these aren't two different sequences of events. It's the same
> > train, the same two lightning strikes, and there is only one pool of
> > water surrounding the embankment and the open train cars. So you tell
> > me, how can the water be stationary relative to the train AND
> > stationary relative to the embankment?
>
> It's the same two lightning strikes, but it is occurring at A on the
> embankment and A' on the train.
>
> You can have a bucket of water that is stationary on the embankment
> and a bucket of water that is stationary on the train.
>
>
>
>
>
> > > There is a single lightning strike at A/A' but A in on the embankment
> > > and A' is on the train. Likewise with the lightning strike at B/B'.
>
> > > > Einstein's gedanken is about ONE pair of events (the lightning
> > > > strikes) and what happens to the light as observed by M and M' for
> > > > that ONE case, not two cases.
>
> > > That is why I am saying Einstein is incorrect. He is trying to have it
> > > both ways. He wants to have a single lightning strike in two reference
> > > frames where the reference frames are not equal.
>
> > What do you mean "equal"?
>
> > The same sequence of events live in a bunch of reference frames all at
> > once.
> > If a sailor falls from the crow's nest of a ship, you can look at that
> > sequence of events from the deck of the ship or you can look at that
> > SAME sequence of events from the shore. This is looking at the SAME
> > sequence of events from two different reference frames.
> > In the reference frame of the ship, the sailor falls in a straight
> > line down and lands at the bottom of the mast. In the reference frame
> > of the shore (because the ship is moving relative to the shore), the
> > sailor falls in a parabola, landing some distance to one side of where
> > he left the crow's nest.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -...
>
> read more »
Bruce Richmond
The mark at A on the tracks and the mark at A' on the train were made
when the two points were together.
M considers the strike to have happen at A. There are scorch marks on
the tracks marking the spot. There are also scorch marks on the
train, but the train is moving relative to the tracks, so the marks on
the train are not where the strike took place in the track frame.
M' considers the strike to have happen at A'. There are scorch marks
on the train marking the spot. There are also scorch marks on the
tracks, but the tracks are moving relative to the train, so the marks
on the tracks are not where the strike took place in the train frame.
>
> > > > The light from A/A' travels through the *same medium* that the
> > > > embankment and the open flatbed train cars are immersed in. The light
> > > > from B/B' does the same thing.
> > > > So how does the light, coming from a single lightning strike (A/A'),
> > > > traveling through a common medium, arrive at the same observer M' both
> > > > simultaneously and not simultaneously as the light from B/B'?
>
> > > It doesn't. If the train contains open flatbed cars, then you are
> > > implying the medium is stationary relative to the embankment.
>
> > No, I'm not. There's no such implication at all. What you know is true
> > is that there is ONE medium, not two.
>
> If there is one medium that is stationary relative to one of the
> frames of reference in Einstein's train thought experiment then that
> means it is moving relative to the other frame of reference which
> means there is a preferred frame of reference.
>
There is only one medium and it is not stationary relative to either
frame, so neither one is preferred.
[snip]
Inertial
"Bruce Richmond" <bsr...@my-deja.com> wrote in message
news:ed15034f-aa9e-482e...@a21g2000yqc.googlegroups.com...
> On Oct 9, 10:52 am, PD <thedraperfam...@gmail.com> wrote:
> Why not use the LET interpertation for the same math. The aether/
> water is not at rest with either the train or the embankment. But
> because of the method used to sync clocks in each frame they both
> measure the wave speed to be the same.
And don't forget that, according to LET, movement through the aether makes
*all* processes run slower, and *all* objects and distances (material and
non-material) compress. In LET this is a physical change to the object
itself (it gets truly compressed when speed in the aether increases, or
expanded when speed in aether decreases) and a physical slowing of the
processes (they run slower when speed in the aether increases, and faster
when speed in the aether decreases).
Bruce Richmond
> "Bruce Richmond" <bsr3...@my-deja.com> wrote in message
But the observer never detects that change because the measuring rod
changes in the exact same way as the object being measured. The
method of clock sync hides the differences in light speed and length
contraction.
mpc755
My scenario has everything to do with the Einstein's train thought
experiment.
mpc755
I understand exactly what is occurring in Einstein's Train Thought
experiment.
Lightning strikes at A/A' and B/B' behave exactly like the waves of
pebbles dropped into stationary pools of water on the train and
stationary pools of water on the embankment.
If there are stationary pools on the train and on the embankment, the
waves the pebbles create from A and B reaches M and the light from A'
and B' reaches M' simultaneously.
If there are stationary pools on the train and on the embankment, the
light waves from A and B reach M and the light wave from A' and B'
reach M' simultaneously.
mpc755
Why is everyone afraid to answer my thought experiment with pebbles
and the waves they create and stationary water on the train and
stationary water on the embankment?
If pebbles are dropped simultaneously at A and A' and pebbles are
dropped simultaneously at B and B', if the waves from A and B reach M
simultaneously do the waves from A' and B' reach M' simultaneously?
mpc755
What if there is water that is stationary on the train and water that
is stationary on the embankment and a lightning strike occur
simultaneously at A' on the train and A on the embankment and another
lightning strike occurs simultaneously at B' on the train and B on the
embankment. If the light from the lightning strikes at A and B travels
through the stationary water on the embankment and reaches M
simultaneously, does the light from the lightning strikes at A' and B'
travel through the stationary water in the train and reach M'
simultaneously?
Bruce Richmond
>
> - Show quoted text -
Because Relativity refers to "empty space". If you look out at the
stars there is empty space between us and them. If there is an aether
out there, there is only one aether between the stars and anything
moving relative to them. So you need to make your theory work with
just one aether.
Inertial
And LET says that every measurement of every physical property of the object
remains unchanged. Even though (for example) if the earth was travelling
fast enough wrt the aether it would be squashed to something almost
disc-shaped
> The
> method of clock sync hides the differences in light speed and length
> contraction.
Not really .. its the combination of the change in length and change in time
and clock sync.
Of course, the method of clock sync is the only sensible clock sync we have.
PD
You say that, but then you say "Forget the Einstein gedanken" just as
we were getting started explaining it to you.
PD
If there were two bodies of water moving past each other, then there
would be a transition layer between them. There would HAVE to be if
the train observer was out in the open. This would mean that if the
train observer moved to one side of the car, into the transition
layer, then he'd be able to see the effect of the incompletely dragged
medium. This has never been observed.
PD
Answer in what way?
It doesn't pertain to the Einstein gedanken, which is done out in the
open so that at best there is ONE medium.
PD
Not as Einstein explained it, no you don't.
You understand the MPC Train Thought Experiment, which is something
completely different than the Einstein Train Thought Experiment.
>
> Lightning strikes at A/A' and B/B' behave exactly like the waves of
> pebbles dropped into stationary pools of water on the train and
> stationary pools of water on the embankment.
>
> If there are stationary pools on the train and on the embankment, the
> waves the pebbles create from A and B reaches M and the light from A'
> and B' reaches M' simultaneously.
>
> If there are stationary pools on the train and on the embankment, the
> light waves from A and B reach M and the light wave from A' and B'
> reach M' simultaneously.
See? That's the MPC Train Thought Experiment, not the Einstein one.
glird
> mpc755 wrote:
> > I understand exactly what is
> > occurring in Einstein's Train
> > Thought experiment.
>
> Not as Einstein explained it, no you > don't.
>
> You understand the MPC Train Thought
> Experiment, which is something
> completely different than the
> Einstein Train Thought Experiment.
Yes.
> << Lightning strikes at A/A' and B/B' behave exactly like the waves of
pebbles dropped into stationary pools of water on the train and
stationary pools of water on the embankment.
If there are stationary pools on the train and on the embankment, the
waves the pebbles create from A and B reaches M and the light from A'
and B' reaches M' simultaneously.
If there are stationary pools on the train and on the embankment, the
light waves from A and B reach M and the light wave from A' and B'
reach M' simultaneously. >>
>
> See? That's the MPC Train Thought
> Experiment, not the Einstein one.
PD is right. In Einstein's, A and A' coincide when a given ray hits
point AA', and B and B' coincide when ray 2 hits BB'. In MPC's, A and
A' are different points than each other in 3-d space and so are b and
B'.
In Einstein, the space between AA' and BB' is empty and light moves
at c wrt to it while the train - thus points A', B' and midpoint M' -
moves to the right at v. in mpc, a luminiferous aether is trapped
within the moving train and is therefore moving wrt to the outside
aether taken as at rest wrt the embankment.
Therefore, as PD said, mpc's conclusions are unrelated to
Einstein's.
BTW, this gedanken experiment by Einstein is to the layman, and
doesn't explain why simultaneity is relative to the states of motion
of different observers' clocks.
glird
them ir point
mpc755
That is where Relativity is incorrect. The aether is more like water
than you give it credit for.
We could say there is one water, but the water on the embankment is
stationary relative to the embankment and the water on the train is
stationary relative to the train.
The same is correct for aether.
For everything to be truly relative in Einstein's Train Thought
Experiment the aether needs to be relative in the embankment frame of
reference and the train frame of reference which means the aether is
stationary relative to both frames of reference.
PD
Then there must be a transition region between the two.
>
> The same is correct for aether.
>
> For everything to be truly relative in Einstein's Train Thought
> Experiment the aether needs to be relative in the embankment frame of
> reference and the train frame of reference which means the aether is
> stationary relative to both frames of reference.
How can a material aether be stationary in both frames of reference at
the same time.
Is the water in a lake stationary relative to the boat AND stationary
relative to the buoy?
mpc755
We see the implications of the dragged aether in many experiments.
'Miller Challenges Einstein'
Explains Ether Drift Research and Function of Interferometer
Dr. Dayton C. Miller - "By George, I never could get zero".
http://www.orgonelab.org/EtherDrift/MillerCase1929.pdf
'The Cosmic Background Radiation and the New Aether Drift'
http://muller.lbl.gov/COBE-early_history/SciAm.pdf
'Combining NASA/JPL One-Way Optical-Fiber Light-Speed Data with
Spacecraft Earth-Flyby Doppler-Shift Data to Characterise 3-Space
Flow'
http://arxiv.org/PS_cache/arxiv/pdf/0906/0906.5404v2.pdf
"The NASA/JPL data is in remarkable agreement with that determined in
other light speed anisotropy experiments, such as Michelson-Morley
(1887), Miller (1933), De- Witte (1991), Torr and Kolen (1981), Cahill
(2006), Munera (2007), Cahill and Stokes (2008) and Cahill (2009)."
(Note: In this article they distinctly refer to space as not
consisting of aether but "a dynamical 3-space, which at a small scale
is a quantum foam system". The point of referring to this article is
to show how the above two aether experiments are in agreement with one
another).
mpc755
If Einstein's Train Thought Experiment was done 'out in the open' then
you are tying the stationary aether to one of the frames of reference,
which is a different thought experiment than the one Einstein
proposes.
Asking, 'Answer in what way?' is hiding from answering the following
question:
If pebbles are dropped into the water simultaneously at A and A' and
pebbles are dropped into the water simultaneously at B and B', if the
mpc755
It's the same thought experiment, but I am starting with pebbles in
the stationary medium of water, moving to flashes of light in the
stationary medium water, moving to flashes of light in the stationary
medium of aether.
PD
No, *I'm* not, you are. Einstein made no presumption that an aether
was present at all.
And in fact, I asked you how you can tell with the information given
that there is an aether tied to *either* frame of reference. I
explicitly asked you how you know that the aether isn't moving
relative to *both* the embankment and the train.
> which is a different thought experiment than the one Einstein
> proposes.
>
> Asking, 'Answer in what way?' is hiding from answering the following
> question:
>
> If pebbles are dropped into the water simultaneously at A and A' and
> pebbles are dropped into the water simultaneously at B and B', if the
> waves from A and B reach M simultaneously do the waves from A' and B'
> reach M' simultaneously?
Sorry, but now you're asking questions about the MPC train thought
experiment, not the Einstein gedanken.
I was interested when you were claiming this has something to do with
Einstein's gedanken, but I'm not interested in a wholly different
example involving two tanks of water and pebbles.
PD
But here's the problem.
You have not addressed what happens in the transition region between
the two relatively moving bodies of water.
You have also made a prediction of what will be observed in terms of
arrival times at M and M' that is in conflict with experiment.
So since you have these two problems that are not resolved, I see no
reason to bang on your model further. Do you?
PD
> not in Einstein's Train Thought Experiment.
>
> Saying it makes a difference shows your limited understanding of the
> Einstein's Train Thought Experiment.
No, I'm sorry, now you're using sentences that Ken Seto uses, and Ken
Seto is insane.
It's you that doesn't understand the Einstein gedanken.
>
> The only thing that matters in Einstein's Train Thought Experiment is
> the flash at A/A' occurring in a single instant
And at a single location.
> and the flash of light
> at B/B' occurring in a single instant
And at a single location.
> and for A and B to be equi-
> distant from M and for A' and B' to be equi-distant from M' and for
> the distance from A to M and B to M to be the same as the distance
> from A' to M' and B' to M'.
>
> Let me ask you about Einstein's Train Thought Experiment with the
> following variation.
Why don't we take up the variation after you've correctly understood
the unvaried case?
> As described in the above sentence, if there is
> are simultaneous lightning strikes at A and A' and there are
> simultaneous lightning strikes at B and B', if the light from A and B
> reaches M simultaneously does the light from A' and B' reach M'
> simultaneously? And in terms of simultaneous, I am referring to any
> frame of reference. In other words, from the perspective of an
> observer on the embankment, if the light from A and B reaches the
> observer at M simultaneously, does the light from the lightning
> strikes at A' and B' reach M' simultaneously?
PD
Ah, ok, now we're back to your passive-aggressive mode of
communication, where you simply repeat the same statement over and
over and over again, without addressing any of the remarks that have
been made about your original claims.
PD
You do realize, don't you, that this is why you don't date much.