Speed: searching the right definition?

[Francis Oldogf]

My english is bad.. My shool is worste..but i have good friends....
The speed has sense if referred always to the gravitational field.. The speed (of object..light..) must be refer.. Nope.. The speed ..the true speed of..the light is not an object ..is a propagatipn, an effect..who can help ?

[John Heath]

On Friday, November 27, 2015 at 5:50:24 AM UTC-5, Francis Oldogf wrote:
> My english is bad.. My shool is worste..but i have good friends....
> The speed has sense if referred always to the gravitational field.. The speed (of object..light..) must be refer.. Nope.. The speed ..the true speed of..the light is not an object ..is a propagatipn, an effect..who can help ?

c = 300 million meters per second. If you measure the speed of light from our sun it turns out to be c. If you move towards the sun at 1/2 c the speed of light still measures c. If you move away from the sun at 1/2 c the speed of light still measures c. It is hard to understand how this could be true however the bottom line is the speed of light will always measure c regardless how you move relative to the source of light. Dr Einstein developed a theory to try to answer the question why the speed of light always measures c. The theory is called the electrodynamics of moving bodies , special relativity , that is based on to assumptions , postulates.

A] the speed of light is constant to all observers.

B] The laws of physics are the same for all speeds , frames of reference.

If you google special relativity and watch a few videos you will gain a general idea.

[nero]

...grazie , Giovanni... i agree with you about the example of the sun ,almost ... the devil is hidden in the almosts ... later we should speak about the almosts ...
to say , here in this grouo , the speed is the space divides the time ,,, it seems to me a little 'old faschion' , naive ..and ambiguous ...because soon somebody can ask for a definition of the space ...( not a definition of the time ..: because here the time is not objective..not subjective ..not subjective for some gravity or movement and oobjective for ...blabla..here the time simply don't exists ..sss )
...space is the distance between two points .. with vacuum inside ? .and if the points , with vacuum inside , are moving ? .. will somebody get dirthy the fingers ?

[Poutnik]

Dne 27/11/2015 v 14:20 John Heath napsal(a):

> On Friday, November 27, 2015 at 5:50:24 AM UTC-5, Francis Oldogf wrote:
>> My english is bad.. My shool is worste..but i have good friends....
>> The speed has sense if referred always to the gravitational field.. The speed (of object..light..) must be refer.. Nope.. The speed ..the true speed of..the light is not an object ..is a propagatipn, an effect..who can help ?
>

> ....................Dr Einstein developed

> a theory to try to answer the question why the speed of light
> always measures c. The theory is called the electrodynamics of
> moving bodies , special relativity , that is based
> on to assumptions , postulates.
>

....

Hmm, while the electrodynamics of moving bodies
is in the title of the introducing article,
I am not aware of it being ever part of the theory name.

Later formulations of SR abandoned relation to electrodynamic,
taking ED effects as consequences of
SR being the theory of space geometry.

--
Poutnik ( the Czech word for a wanderer )

Knowledge makes great men humble, but small men arrogant.

[nero]

..ciao, Poutnik .. was you wandering around Jerevan ? ..many goats ? with long beards and no moustache ?
an easy easy problem for Dr. E , his friends and the other-ones ..
.... over a long street ,i have the car A and at 3 millions kms the car B and many similar clocks along the street ..
if i seng a light from A , the car B receives it after 10 secs (looking the clocks street..)
if i send a light from A and , after that , the car B makes 300 000 kms .. B receives the ligth after 11 secs ...
if i send a ligth from A and , after that , the car A and B make 300 000 kms , the distance between A and B is remained always 3 millions kms ...looking the street clock , how many secs the light imploied in the last situation ?

[Poutnik]

Dne 29/11/2015 v 16:43 nero napsal(a):

> Il giorno sabato 28 novembre 2015 09:11:41 UTC+1, Poutnik ha scritto:

>>
>> Hmm, while the electrodynamics of moving bodies
>> is in the title of the introducing article,
>> I am not aware of it being ever part of the theory name.
>>
>> Later formulations of SR abandoned relation to electrodynamic,
>> taking ED effects as consequences of
>> SR being the theory of space geometry.
>>

>

> ...ciao, Poutnik .. was you wandering around Jerevan ? ..many goats ? with long beards and no moustache ?


No, I have never been in Armenia nor near Caucasus.

> an easy easy problem for Dr. E , his friends and the other-ones ..

> ..... over a long street ,i have the car A and at 3 millions kms the car B and many similar clocks along the street ..

> if i seng a light from A , the car B receives it after 10 secs (looking the clocks street..)
> if i send a light from A and , after that , the car B makes 300 000 kms .. B receives the ligth after 11 secs ...
> if i send a ligth from A and , after that , the car A and B make 300 000 kms , the distance between A and B is remained always 3 millions kms ...looking the street clock , how many secs the light imploied in the last situation ?
>

Why not to read some popular book about the SR basics ?

The answer depends on speed of cars wrt to frame of reference
and you have not provided the speed.

[John Heath]

Let us divide electrodynamics into electric force and magnetic force. The magnetic force may be considered a consequence of SR caused by length contraction of a electric force. It is the magnetic force that is tossed into the trash bin by SR.

An interesting note is the phrase length contraction can not be found in the electrodynamics of moving bodies. This came from the Minkowski interpretation of SR in 1907. Einstein objected to this calling it superfluous. I suspect his real thoughts would use stronger language but Minkowski was he former math teacher so some respect is do. Einstein used the simultaneity of time for length contraction not the physical contraction of a rigid rod. The use of length contraction in geometry was only a math convenience to keep track of the the simultaneity of time. Unfortunately it is the Minkowski interpretation of SR that is taught in college. Best to follow Einstein not Minkowski for SR.

[Poutnik]

Dne 29/11/2015 v 18:25 John Heath napsal(a):

> On Saturday, November 28, 2015 at 3:11:41 AM UTC-5, Poutnik wrote:

>>
>> Hmm, while the electrodynamics of moving bodies
>> is in the title of the introducing article,
>> I am not aware of it being ever part of the theory name.
>>
>> Later formulations of SR abandoned relation to electrodynamic,
>> taking ED effects as consequences of
>> SR being the theory of space geometry.
>>
>
> Let us divide electrodynamics into electric force and magnetic
> force.

This is not possible, as it is coordinate dependent.

Lorentz transform partially transforms
charge and current densities across different frames.

[Poutnik]

Dne 29/11/2015 v 18:25 John Heath napsal(a):

> An interesting note is the phrase length contraction can not be found in the electrodynamics of moving bodies. This came from the Minkowski interpretation of SR in 1907. Einstein objected to this calling it superfluous. I suspect his real thoughts would use stronger language but Minkowski was he former math teacher so some respect is do. Einstein used the simultaneity of time for length contraction not the physical contraction of a rigid rod. The use of length contraction in geometry was only a math convenience to keep track of the the simultaneity of time. Unfortunately it is the Minkowski interpretation of SR that is taught in college. Best to follow Einstein not Minkowski for SR.
>

Physica contraction was AFAIK suppoed at some time
by Lorentz within Lorentz aether theory.

[John Heath]

I can see why you would say this and I salute you for sticking to your guns. A better intuitive description of how length contraction leads to tossing a magnetic force in the trash bin can be found at wikipedia with this link.

https://en.wikipedia.org/wiki/Length_contraction

[Poutnik]

Dne 29/11/2015 v 19:03 John Heath napsal(a):

Even better is saying
electrostatic and magnetic force effects
are 2 different manifestations
of the single EM force/interaction.

Protons, electrons and neutrons
have their own electric charges ( neutron internally )
and all of them have magnetic momentum.

Similarly as wave and particle attributes
are 2 different manifestations
of dual character of quantum objects.

[John Heath]

Yes it would be fuller with more interesting options to say 2 manifestations of electrostatic and magnetic forces. Then again the chance to toss a fundamental force in nature like magnetism straight in the trash bin is rare and tempting as it is one less force to deal with , a step towards a simplification. At the end of the day it is hard to say one way or the other as it is outside the stage of measurements made. How could one test for proof that it is the movement of a charge that causes a magnetic force or length contraction of a electrostatic force. I favor the simpler road of no magnetism just the effective length contraction of a electrostatic force. However if I were taxed to prove it I could not do so.

>
> Protons, electrons and neutrons
> have their own electric charges ( neutron internally )
> and all of them have magnetic momentum.

Yes but these particles are spinning like tops as indicated in PET scans for magnetic resonance images. Where there is movement there is effective length contraction. It is a no win as it can not be proven that magnetism is real or the result of length contraction. If they found some S or N mono poles it would be a different story but they have not found any so far.

>
> Similarly as wave and particle attributes
> are 2 different manifestations
> of dual character of quantum objects.
>

Yes it true and wonderful predictions have come from quantum mechanics. However cracks are already starting in the uncertainty principle where which way information can be detected while maintaining a interference pattern in a photon double slit experiment. It was done in Toronto university in Canada. They used a feather instead of a hammer to do this. And there is the qubit quantum computer that is always just around the corner but never realized. 20 years and still no verifiable speed up by qubit gates causes one to question QM. QM is clearly pointing in the right direction from success in making accurate predictions and advances in technology such as a cell phone but there is some small part of it that is wrong when it comes to the true nature of entanglement and the literal application of the uncertainty principle. 99 percent of QM is a correct. But that last 1 percent of Star Trek notions of entanglement are not panning out in the real world.

[nero]

.. i write slowly and think slowerly ....: but the grass in Armenia has the best quality and Minky -friendly by our club - knew nothing about it , probably .... .o0 sometime i think that you like more to speak around problems than to go deepply inside and to get dirty the fingers Oo. ...
Questionary :
From a mountain of your dear Caucaso , i send an e m signal that is received after 4 000 km at Svalbard islands and at Spain ....
a) the signal is received at the same time
b) first Spain receives
c) first Svalbard receives

[Poutnik]

On 11/30/2015 02:58 PM, nero wrote:
> Questionary :
> From a mountain of your dear Caucaso , i send an e m signal that is received after 4 000 km at Svalbard islands and at Spain ....
> a) the signal is received at the same time
> b) first Spain receives
> c) first Svalbard receives

It depends on many not provided info,
so all 3 answers may be right.

Major factor are ionospheric conditions
and therefore real path length of the signal.

Minor factor are ionospheric delays.

Relativistic effects are negligible,
compared to above.

[Carl Heinz Krueger]

Poutnik wrote:

> Protons, electrons and neutrons have their own electric charges (
> neutron internally ) and all of them have magnetic momentum.

Describe "neutron internally".

[Carl Heinz Krueger]

Poutnik wrote:

> Protons, electrons and neutrons have their own electric charges (
> neutron internally ) and all of them have magnetic momentum.

Describe "neutron internally".

[Poutnik]

What of these 2 words should I explain ?

[Carl Heinz Krüger]

суббота., Mon, 30 Nov 2015 18:38:22 +0100 пользователь Poutnik написал:

> On 11/30/2015 05:15 PM, Carl Heinz Krueger wrote:
>> Poutnik wrote:
>>
>>> Protons, electrons and neutrons have their own electric charges (
>>> neutron internally ) and all of them have magnetic momentum.
>>
>> Describe "neutron internally".
>
> What of these 2 words should I explain ?

You said neutrons carry electric charges. Me?

[Poutnik]

Neutron internally.

1 up quark +2/3 e, 2 down quarks -1/3 e each,
making internally charge distribution,
causing as a final consequence a magnetic momentum.

--
Poutnik ( the Czech word for a wanderer )

Knowledge makes a great man humble, but a small man arrogant.

Eventual Wikipedia articles are provided with intention
of a convenient reference, not as an evidence, argument,
and usually not as a primary source of my knowledge.

[nero]

You know well , sometime the devil is in the negligible things ..
however , thanks and compliment for the answer ...and for theway in which you avoid the devil ...
Now , ...From the same dear mountain , we send in the same directions signals and the detectors have the same atmospheric , magnetic , elec and and ....conditions and also a very higth -devilly extraordinary - sensibility ... A ) B) and C) again hoping their season ...

[Poutnik]

On 12/01/2015 08:31 AM, nero wrote:


> Now , ...From the same dear mountain,we send in the same directions

> signals and the detectors have the same atmospheric , magnetic
> , elec and and ....conditions and also a very higth -devilly
> extraordinary - sensibility ... A ) B)
> and C) again hoping their season ...

Then the result will depend on the observer.
Also, it would need somebode more skilled than me,
as rotating system is involved.

[mlwo...@wp.pl]

W dniu wtorek, 1 grudnia 2015 10:48:43 UTC+1 użytkownik Poutnik napisał:

> Then the result will depend on the observer.

Yeah. A sane observer and an observer brainwashed
by The Shit will notice different things to happen.

[nero]

..i think , you understoo the where better than the Greit Developer ... for the how , this is my opinion ....
the light shows to be an effect : because its speed is not influenced by the speed of the generating body ...and it , the light , goes previously in the vacuum ... and so , it has an inertial motion like a pendulum or bodies ... and , if the generating and receiving bodies are jointed and moving , the light ' travel becomes shorter or longer ...
how is the change of the travel ? of course , the quantity of change is directly proportional to the time of the travel and to the speed of the moving source - receiver ...: that is showed quantitatively and qualitatively in the Allan-around-the -world exp ( see also the topic ''w Allan'')
..to the welth of the beard of all goats without mustache ...
( there the Developer&fiends made and fooded the ambiguity remarked by Dingle ...)

[Poutnik]

On 12/02/2015 09:17 AM, nero wrote:
> Il giorno martedì 1 dicembre 2015 10:48:43 UTC+1, Poutnik ha scritto:
>> On 12/01/2015 08:31 AM, nero wrote:
>>
>>
>>> Now , ...From the same dear mountain,we send in the same directions
>>> signals and the detectors have the same atmospheric , magnetic
>>> , elec and and ....conditions and also a very higth -devilly
>>> extraordinary - sensibility ... A ) B)
>>> and C) again hoping their season ...
>>
>> Then the result will depend on the observer.
>> Also, it would need somebode more skilled than me,
>> as rotating system is involved.
>>
>>
>> --
>> Poutnik ( the Czech word for a wanderer )
>

> ...i think , you understoo the where better than the Greit Developer ... for the how , this is my opinion ....

> the light shows to be an effect : because its speed is not influenced by the speed of the generating body ...and it , the light , goes previously in the vacuum ... and so , it has an inertial motion like a pendulum or bodies ... and , if the generating and receiving bodies are jointed and moving , the light ' travel becomes shorter or longer ...
> how is the change of the travel ? of course , the quantity of change is directly proportional to the time of the travel and to the speed of the moving source - receiver ...: that is showed quantitatively and qualitatively in the Allan-around-the -world exp ( see also the topic ''w Allan'')
> ..to the welth of the beard of all goats without mustache ...
> ( there the Developer&fiends made and fooded the ambiguity remarked by Dingle ...)
>

Are you aware
the analysis of your text is difficult due the form you are using ?

[Tom Roberts]

On 11/29/15 11/29/15 11:25 AM, John Heath wrote:
> Let us divide electrodynamics into electric force and magnetic force. The
> magnetic force may be considered a consequence of SR caused by length
> contraction of a electric force. It is the magnetic force that is tossed into
> the trash bin by SR.

No. It is the concept of "dividing electrodynamics into electric force and
magnetic force" that is "tossed into the trash bin".

In classical electrodynamics, which is the classical (non-quantum) theory of
E&M, the electromagnetic force is a 2-form, not two separate 3-vector fields as
you suppose (or just one 3-vector field after "magnetic force that is tossed
into the trash bin").

> An interesting note is the phrase length contraction can not be found in the
> electrodynamics of moving bodies.

Yes. We have learned A LOT about SR since 1905. And the terminology has morphed
to match.

> Einstein used the simultaneity of time
> for length contraction not the physical contraction of a rigid rod.

Not just Einstein, that _IS_ how the theory describes it. "Length contraction"
is about MEASUREMENTS of moving objects, not about any sort of "physical change"
in them.


> [... nonsense omitted] Best to follow Einstein not
> Minkowski for SR.

No. Best to follow THE THEORY. Einstein's early writings had several mistakes,
corrected in modern textbooks. Even in later writings Einstein used archaic
terminology.


Tom Roberts

[Maciej Woźniak]

Użytkownik "Tom Roberts" napisał w wiadomości grup
dyskusyjnych:esqdnVjVNPpRmsLL...@giganews.com...

|Not just Einstein, that _IS_ how the theory describes it. "Length
contraction"
|is about MEASUREMENTS of moving objects, not about any sort of "physical
change"
|in them.

In other words, relativistic moron refuted the common
sense prejudice, that measurement describes physical
state of object.

[Carl Heinz Krüger]

суббота., Wed, 02 Dec 2015 18:44:57 +0100 пользователь Maciej Woźniak
написал:

>> Not just Einstein, that _IS_ how the theory describes it. "Length
>> contraction" is about MEASUREMENTS of moving objects, not about any
>> sort of "physical change" in them.
>
> In other words, relativistic moron refuted the common sense prejudice,
> that measurement describes physical state of object.

This is how is done in Modern Science. First you say ie that the length of
a wave is changed, then when Pentcho reply that "it cannot be changed",
you insist is changed, whereafter you admit that "no physical change in
them occurs".

[JanPB]

In English you don't put the comma before "that". (Are you going to argue
this to death too?)

--
Jan

[Maciej Woźniak]

Użytkownik "JanPB" napisał w wiadomości grup
dyskusyjnych:1d3ace28-5565-4dd2...@googlegroups.com...

My mistake. So, in other words, relativistic moron refuted
the common sense prejudice that measurement describes
physical state of object.
Better?

[JanPB]

Yes. But your constant use of the phrase "relativistic moron" (and similar
oddly childlike phrases) immediately indicates you feel powerless.

--
Jan

[Maciej Woźniak]

Użytkownik "JanPB" napisał w wiadomości grup

dyskusyjnych:3c216802-0a7e-4a06...@googlegroups.com...

> My mistake. So, in other words, relativistic moron refuted
> the common sense prejudice that measurement describes
> physical state of object.
> Better?

|Yes. But your constant use of the phrase "relativistic moron" (and similar
|oddly childlike phrases) immediately indicates you feel powerless.

Just an imagination of a feeling powerless relativistic moron,
constantly yelling "not even wrong!!!" and similiar oddly
childlike phrases.

[kenseto]

On Wednesday, December 2, 2015 at 10:01:34 AM UTC-5, tjrob137 wrote:
> On 11/29/15 11/29/15 11:25 AM, John Heath wrote:
> > Let us divide electrodynamics into electric force and magnetic force. The
> > magnetic force may be considered a consequence of SR caused by length
> > contraction of a electric force. It is the magnetic force that is tossed into
> > the trash bin by SR.
>
> No. It is the concept of "dividing electrodynamics into electric force and
> magnetic force" that is "tossed into the trash bin".
>
> In classical electrodynamics, which is the classical (non-quantum) theory of
> E&M, the electromagnetic force is a 2-form, not two separate 3-vector fields as
> you suppose (or just one 3-vector field after "magnetic force that is tossed
> into the trash bin").
>
>
> > An interesting note is the phrase length contraction can not be found in the
> > electrodynamics of moving bodies.
>
> Yes. We have learned A LOT about SR since 1905. And the terminology has morphed
> to match.
>
>
> > Einstein used the simultaneity of time
> > for length contraction not the physical contraction of a rigid rod.
>
> Not just Einstein, that _IS_ how the theory describes it. "Length contraction"
> is about MEASUREMENTS of moving objects, not about any sort of "physical change"
> in them.

Why do you keep using the word MEASUREMENTS when no such MEASUREMENTS ever been make? SR uses the LT to predict the projected length of a moving meter stick and the result is 1/gamma.

[JanPB]

No, it's not imagination. You xerox phrases which are designed to be merely
vaguely inflammatory. We both know they are nonsense or else the repetition
would stop. It also means you have no arguments about physics, only magic
incantations.

I also recommend that you use your own words when arguing with people rather
than cutting and pasting their phrases as your "responses". It makes it look
like you have nothing to say.

--
Jan

[nero]

..dear friend Poutnik , may be the guilty is my english or my sintaxy ..but also the real difficulties of the things ... on the contrary , Dr Einstein should had understood easier all without mistakes and paradoxies ..
my opinion ( and the Allan-around-theworld exp) is that : you receive ,on the same distance , signals from Caucaso earlier in Spain than in Svalbard .. how much ? The earth is moving from Spain to Caucaso at speed of more than 0.3 km.sec , so , during the signal'travel ,that path is become shorter more than 4 meters !
The waves go in vacuum , fixed in the gravitational field that is not rotating ..like the inertial pendullum ..so thewaves make a doppler through a moving body , but you cannot realize staying in that body and measuring the frequencies ..you can realize measuringthetimes in different directions ..and paradoxally the topic 'the got of Dingle ' shows well that situation ..

[Maciej Woźniak]

Użytkownik "JanPB" napisał w wiadomości grup

dyskusyjnych:1832ffc2-6b90-4d94...@googlegroups.com...

On Wednesday, December 2, 2015 at 1:38:48 PM UTC-8, Maciej Woźniak wrote:
> Użytkownik "JanPB" napisał w wiadomości grup
> dyskusyjnych:3c216802-0a7e-4a06...@googlegroups.com...
>
>
> > My mistake. So, in other words, relativistic moron refuted
> > the common sense prejudice that measurement describes
> > physical state of object.
> > Better?
>
> |Yes. But your constant use of the phrase "relativistic moron" (and
> similar
> |oddly childlike phrases) immediately indicates you feel powerless.
>
> Just an imagination of a feeling powerless relativistic moron,
> constantly yelling "not even wrong!!!" and similiar oddly
> childlike phrases.

|No, it's not imagination. You xerox phrases which are designed to be merely
|vaguely inflammatory. We both know they are nonsense or else the repetition
|would stop. It also means you have no arguments about physics, only magic
|incantations.

Just an imagination of a feeling powerless relativistic moron,
constantly yelling "not even wrong!!!" and similiar oddly
childlike phrases.


|I also recommend that you use your own words when arguing with people
rather

Buddy, do I really have to constantly repeat, what can you
do with your recommendations?

[Paul B. Andersen]

On 03.12.2015 09:17, nero wrote:
> my opinion ( and the Allan-around-theworld exp) is that : you receive ,on the same distance ,
> signals from Caucaso earlier in Spain than in Svalbard .. how much ? The earth is moving from
> Spain to Caucaso at speed of more than 0.3 km.sec , so , during the signal'travel,
> that path is become shorter more than 4 meters !

Quite right.
The speed of light is isotropic in the Earth centred non-rotating frame.
Look up the Sagnac effect.
https://paulba.no/pdf/sagnac_ring.pdf
https://paulba.no/pdf/four_mirror_sagnac.pdf

--
Paul

https://paulba.no/

[JanPB]

I know this is the only argument you have.

--
Jan

[mlwo...@wp.pl]

200 hundred years ago your belief in eternal,
immutable mathematical truth would be groundless.
Now it's only funny.

[mlwo...@wp.pl]

Should be 2 hundred, of course.

[nero]

Il giorno venerdì 27 novembre 2015 11:50:24 UTC+1, Francis Oldogf ha scritto:
> My english is bad.. My shool is worste..but i have good friends....
> The speed has sense if referred always to the gravitational field.. The speed (of object..light..) must be refer.. Nope.. The speed ..the true speed of..the light is not an object ..is a propagatipn, an effect..who can help ?

quite rigth ...good : earth centrated non-rotating frame ..
..and the devil came out in particulars
: if i measure one-way the speed'light towordSpain ..or i measure the time in the same controlled path , that time come out shorter than in opposite direction ...of course ,it is isotropic !
so the necessity of a redefinition of the word ' speed' depending to the direction ..or the use of different words for
propagation of e m signal
propagation in bodies (isotropic to body)
speed of bodies

[John Heath]

On Wednesday, December 2, 2015 at 10:01:34 AM UTC-5, tjrob137 wrote:

This reminds myself of a funny Einstein story. 1936 Einstein and Rosen submitted a paper on the existence of gravitational waves for publication. It was rejected with a 10 page report explaining why the conclusions of the paper were incorrect. Einstein's response was

Quote

Dear Sir,

We (Mr. Rosen and I) had sent you our manuscript for publication and had not authorized you to show it to specialists before it is printed.

end of quote

Ha

[JanPB]

Makes no difference.

--
Jan

[Maciej Woźniak]

Użytkownik "JanPB" napisał w wiadomości grup

dyskusyjnych:abffffbc-c715-437c...@googlegroups.com...

Yes. Your belief is only funny in both cases.

[nero]

..................................
..if i can measure that the travel for Spain takes less time ...i can make the same exp in a lab of one kmand , if i have the rigth tecnicals , i get the same evidence ..
so i can extablishe that my lab is moving as regards as the waves ...so Dr. E did't told in that way ( first postulate )..
a little step dedicated to the searching of human relationship and knowledge of Ken Fisher

[Francis Oldogf]

..correction :
...if i can make the same exp in a lab long one km , and , if i have the rigth tecnicals...

[Paul B. Andersen]

I am not sure what you are trying to say, but if it is that
you can measure the velocity of your lab relative to something
outside the lab, (say your lab is a closed Faraday cage with
no windows), then you are wrong.
What you can measure, however, given the right instruments,
is that your lab is accelerating at ~9.8 m/s^2 upwards,
and that it is rotating with an angular velocity ~0.0000792 rad/s
around an axis with an angle to the floor equal to your latitude.
(The axis is pointing roughly towards Stella Polaris).

--
Paul

https://paulba.no/

[nero]

..thanks to Anderson ..he comes in field figthing with rigth reasons , so everyone can learn and speak..
i agree with your explanation about gravity and angular reliefments..
but if we come back to the reliefment in Spain ( the apparent speed of light !)...also that measure can be a kind of confirmation of your same relieved situation , coming from gravity and angularity ..
of course now , we have not the instrument for the reliefment in Spain ...and less and less for making the same reliefment in a lab of one km ...but that incapacity , probable, is onlyfor our days ..tomorrow , surely , we could do it ..
And we come back to the capacity of measuring the speed of light only one-way !
my opinion : the first postulate is wrong in many ways ..the second is ambiguous ..

[Gary Harnagel]

On Sunday, December 6, 2015 at 3:02:00 AM UTC-7, nero wrote:
>
> my opinion : the first postulate is wrong in many ways

Opinions are not evidence. Saying that P1 is wrong doesn't make it wrong.
Point out the evidence that P1 is wrong.

"Extraordinary claims require extraordinary evidence." - Marcello Truzzi

> ..the second is ambiguous ..

What can possibly be ambiguous about laying out a distance and timing
how long it takes light (or anything else) to travel said distance?

Gary

[John Heath]

Hi Nero

We do have the technology to make your measurements. It was done in the late 1960s with the Hafele-Keating experiment. That data shows that you are correct as the SR effect was not the same for the east and west bound planes. From this you could conclude that SR is wrong. The Hafele-Keating team felt no need to say SR was wrong as they were armed with the broader and more complete theory of GR. At the north or south pole SR is fine. At the equator we are moving 1000 miles per hour east therefore SR must be adjusted for this. The 2 postulates hold true once the adjustment for the earth moving 1000 MPH east at the equator are made.

[nero]

( in almost all my life i was fisher , now i am almost agricoltur ..so my brain can work with few things at the same moment ..)
: step by step we get that
1) the lightspeed is isotropic and earth centred non-rotaing frame -better if 'fixed stars centred ...'-
2) at the distance of 4000 km from Caucaso , we receive signals first in Spain , then in Svalbard and then in Mongolia ,like apparently the light speed is different..
( however in the three places we receive the same frequency signal, because we are in a doppler .. : i get the qualitative and quantitative goal from Allan exp ..if Truzzi agree.. Hafele was confused ...)
The second postulate is ambiguous because does't say how to take the measure of light speed ; Dingle explained better that ...
The first postulate , for simple minds like i am , means that you cannot from exps understand if a lab is moving ...but you can show a moving lab obseving
1)the falling stones ..
2)the raising ballons ..
3)the boiling steams..
4)the measure of one-way light speed..
5)the bodies 'accelerating strenght in air or vacuum ..
6)the Sagnac exp., jointed to measure of gravity..
7)the pendulum , jointed to measure of gravity.. and..and
The Black postulate ? Each exp shows true speed 'lab, relatively to its universal gravitational field , having the necessary sensibility in instrument or making the necessary number of prooves ..

[Poutnik]

Dne 07/12/2015 v 10:42 nero napsal(a):

> 1) the lightspeed is isotropic and earth centred non-rotaing frame -better if 'fixed stars centred ...'-

LS is isotropic in all (in GR locally ) inertial frames.

Problem is stars are not fixed.

Much more practicle is ECI - Earth Centered inertial frames,
fixes to distant stars to have minimal movement.

Non inertiality caused by Earth orbiting the Sun and the Earth-Moon
barycentre can be neglected for most of measurements.
If not, results can be corrected to them.

> 2) at the distance of 4000 km from Caucaso , we receive signals first in Spain , then in Svalbard and then in Mongolia ,like apparently the light speed is different..

The result depends on if evaluated in ECI frame
or in Earth "natural" non inertial rotating frame.

> ( however in the three places we receive the same frequency signal, because we are in a doppler .. :

There is no Doppler effect, as the do not move each to other.

> The second postulate is ambiguous because does't say how to take the measure of light speed

No, it is not ambigious. How speed is defined is given.
Methodology is not part of physical theories.

> The first postulate , for simple minds like i am , means that you cannot from exps understand if a lab is moving ...but you can show a moving lab obseving

There is strict need to distinguish linear and angular movement.

There is no absolute detectable linear speed, only relative one.

OTOH, absolute* rotation speed is measureable,
e.g. by laser ring interferometers.

*absolute is not fully exact, as this value
is subject of SR time dilation.

--
Poutnik ( the Czech word for a wanderer )

Knowledge makes great men humble, but small men arrogant.

[Paul B. Andersen]

On 06.12.2015 15:23, John Heath wrote:
>
> We do have the technology to make your measurements.
> It was done in the late 1960s with the Hafele-Keating experiment.
> That data shows that you are correct as the SR effect was not
> the same for the east and west bound planes.

This is plain nonsense.
SR doesn't apply in the curved spacetime in the vicinity of
the Earth, but if you by the "SR effect" mean the time dilation
caused by the the speed in _the non rotating ECI frame_
then the difference in the proper times of the East going and
West going planes is because the speed of the planes are very
different in the non rotating frame.
So SR correctly predicts that times should be different.

https://paulba.no/pdf/H&K_like.pdf

> From this you could conclude that SR is wrong.

Quite the contrary.
Look at the idealized H&K like thought experiment above.
The planes are all the time at the same
gravitational potential, so we can use SR.
Since SR only applies in flat space time, and the speed
of light is constant in an inertial frame, we can pretend
that the non rotating Earth-centred frame (ECI-frame) is
such an inertial frame.
Since they start and end their journeys at the same events,
the difference in the proper times of plane B and C is
according to SR:
\tau_B - \tau_C = [sqrt(1 - (v_B/c)^2)-sqrt(1-(v_C/c)^2)] t,
where v_B and v_C are the speeds of plane B and plane C
in the ECI frame.

An approximated equation will be:
\tau_B - \tau_C = [(1-v_B^2/2c^2)-(1-v_C^2/2c^2))] t
= [v_C^2/2c^2-v_B^2/2c^2] t

Note that combining equation (4) and (5) in the reference above yields:
\tau_B -\tau_C = [v_C^2/2c^2-v_B^2/2c^2] \tau_A

Which is in accordance with what was measured in the H&K experiment.
https://paulba.no/paper/Hafele.pdf
see equation (1)

> The Hafele-Keating team felt no need to say SR was wrong as they were armed
> with the broader and more complete theory of GR.

The H&K confirmed SR as shown above.
But to compare the clocks in the planes with the ground clock
GR must obviously be used since the clocks are at different
gravitational potential.

--
Paul

https://paulba.no/

[mlwo...@wp.pl]

W dniu poniedziałek, 7 grudnia 2015 13:35:02 UTC+1 użytkownik Paul B. Andersen napisał:

> This is plain nonsense.
> SR doesn't apply in the curved spacetime in the vicinity of
> the Earth, but if you by the "SR effect" mean the time dilation
> caused by the the speed in _the non rotating ECI frame_
> then the difference in the proper times of the East going and
> West going planes is because the speed of the planes are very
> different in the non rotating frame.
> So SR correctly predicts that times should be different.

You know, I have a theory, that sharks should
eat grass.
My theory is experimentally confirmed. How?
Sharks don't eat grass, but they should.
And proper sharks would.

[nero]

..Poutnik .. we agree that :1) the light speed is isotropic and earth centred inertial frame.. 2) the earth is rotating ...
joint the two things and conclude ! So the quantity of local rotation is a doppler relatively to the light speed ... harder it is to reveil because , having inside the doppler all instruments , you cannot measure frequencies ' differences ...
The ambiguity of P2 is the fact that Dr E don't spoke about ICE , doppler etc..: also today the discussions live loudly for that ambiguity..
The Sagnac exp , of course, can give to us only the angular rotation ..but with gravity direction' instrument , we can calculate the distance of its center ..and with the gravitometer we can have the changement ...: so we have all numbers .. and , if Sagnac tell to you '' you are stopped !'' but the center of gravity is changing and the gravitometer is changing ..you can have the true speed , the inetrial speed without rotation etc ...

[Poutnik]

On 12/08/2015 10:48 AM, nero wrote:
> ...Poutnik .. we agree that :1) the light speed is isotropic and earth centred inertial frame.. 2) the earth is rotating ...

> joint the two things and conclude !

Conclusion is that light speed on accelerating frame is not isotropic.

> So the quantity of local rotation is a doppler relatively to the light
speed ...

Doppler was a person.

> harder it is to reveil because , having inside the doppler all instruments , you cannot measure frequencies ' differences ...

There is no Doppler effect
between 2 object without mutual relative motion.

[nero]

..thanks for the specification about doppler and Doppler ..( i was thinking that doppler could be a choice of humility like i and I , english and English ..)
...:' conclusion is that the ligth speed on accelerated frame is not isotropic '..
but Spain and Mongolia are in the same frame and so its are not accelerated each other ..or not ?

[Poutnik]

On 12/10/2015 09:42 AM, nero wrote:
>>
>> Conclusion is that light speed on accelerating frame is not isotropic.
>>> So the quantity of local rotation is a doppler relatively to the light
>> speed ...
>>
>> Doppler was a person.
>>
>

>> There is no Doppler effect
>> between 2 object without mutual relative motion.
>

> ...thanks for the specification about doppler and Doppler ..( i was thinking that doppler could be a choice of humility like i and I , english and English ..)
> ....:' conclusion is that the ligth speed on accelerated frame is not isotropic '..

> but Spain and Mongolia are in the same frame and so its are not accelerated each other ..or not ?
>

Both the person and the effect have the capital D.
Doppler without the effect is a person name.
But I would put the grammar aside.

Spain and Mongolia are in in all frames together.
But some frames are ( in GR locally ) inertial,
and some are accelerating.

In inertial frame, where Spain, Mongolia and all is moving and
accelerating,
the closing speed of light wrt rotating Earth surface is anisotropic.

In Earth natural frame, where Spain, Mongolia and all is standing,
the light speed wrt the accelerating frame is anisotropic.

--
Poutnik ( the Czech word for a wanderer )

Knowledge makes a great man humble, but a small man arrogant.

Eventual Wikipedia articles are provided with intention
of a convenient reference, not as an evidence, argument,
and usually not as a primary source of my knowledge.

[nero]

..thanks again for your specifications and informations ..i agree not completely , btw thanks ..

[nero]

Il giorno giovedì 10 dicembre 2015 17:23:53 UTC+1, Poutnik ha scritto:

..( it is easy to understand that i am an oldog very slow..)
dear Poutnik , if you are not wandering ..
we can call differently the same goal : anisotrophy or reveiled different time in receiving waves at the same distance ..but this is a way to understand that a lab long 4000 km is moving ...
Galileo was saying : staying in a ship and looking an other moving ship , it is not possible to extablish who is moving with exps in closed room....
Dr. E was saying : staying in a train and looking from window an other moving train ..etc..
but using the anisotrophy it is possible , like alling stones , raising balloons , speed'light one-way etc..

[Poutnik]

Dne 12/12/2015 v 09:44 nero napsal(a):

> dear Poutnik , if you are not wandering ..
> we can call differently the same goal : anisotrophy or reveiled different time in receiving waves at the same distance ..but this is a way to understand that a lab long 4000 km is moving ...
> Galileo was saying : staying in a ship and looking an other moving ship , it is not possible to extablish who is moving with exps in closed room....
> Dr. E was saying : staying in a train and looking from window an other moving train ..etc..
> but using the anisotrophy it is possible , like alling stones , raising balloons , speed'light one-way etc..
>

But the point is the linear speed is always relative,
related to an arbitrary rest.

OTOH, proper acceleration is not relative,
you feel the same press in the seat,
or objects the same stress,
independent on coordinates.

Similarly angular speed is not relative in way
the rotating angular speed can be measured.
Still, measured value of angular speed
is subject of time dilation, diven by relative speed
of observer and rotating object.

--
Poutnik ( the Czech word for a wanderer )

[John Gogo]

Doppler is based on sound not light.

[nero]

..a little , i think to understand your sigth'point ..but , in the delay of the received wave in Mongolia (for example!), the influence of acceleration is very low confronted with the apparent changement of the path ( and calculable)....

[Poutnik]

Dne 13/12/2015 v 09:51 nero napsal(a):

> Il giorno sabato 12 dicembre 2015 09:51:14 UTC+1, Poutnik ha scritto:

>> But the point is the linear speed is always relative,
>> related to an arbitrary rest.
>>
>> OTOH, proper acceleration is not relative,
>> you feel the same press in the seat,
>> or objects the same stress,
>> independent on coordinates.
>>
>> Similarly angular speed is not relative in way
>> the rotating angular speed can be measured.
>> Still, measured value of angular speed
>> is subject of time dilation, diven by relative speed
>> of observer and rotating object.
>>
>> --

> ...a little , i think to understand your sigth'point ..but ,

> in the delay of the received wave in Mongolia (for example!),
> the influence of acceleration is very low confronted with the
> apparent changement of the path ( and calculable)....
>

Can you elaborate that ?

[nero]

..are you asking a numerical elaboration ? not easy for me ..and sincerly i don't see the contribuition of some acceleration , but i can mistake ..
we told that the waves go isotropically as regards as the earth centred etc also if the starting point(Caucaso) is moving
the receiving point (Spain and Mongolia) is moving too and , while the wave is traveling to Spain , this point is coming nearer of around 4 meters and so the travel is shorter like the time ...in Mongolia it happens the contrary ..
i think that Sagnac has nothing to do here , also ...

[mlwo...@wp.pl]

W dniu sobota, 12 grudnia 2015 09:51:14 UTC+1 użytkownik Poutnik napisał:

> But the point is the linear speed is always relative,
> related to an arbitrary rest.

Only in a relativistic moron's dream.
In the world we inhabit, speed is a derivative of the position,
position is a derivative of the coordinates, and sane people
usually use absolute coordinates.

[Poutnik]

On 12/14/2015 10:55 AM, nero wrote:
> Il giorno domenica 13 dicembre 2015 12:28:50 UTC+1, Poutnik ha scritto:
>>
>>> ...a little , i think to understand your sigth'point ..but ,
>>> in the delay of the received wave in Mongolia (for example!),
>>> the influence of acceleration is very low confronted with the
>>> apparent changement of the path ( and calculable)....
>>>
>>
>> Can you elaborate that ?
>

> ...are you asking a numerical elaboration ? not easy for me ..and sincerly i don't see the contribuition of some acceleration , but i can mistake ..

I have rather meant to better explain what you mean,
as I did not get it.

> we told that the waves go isotropically as regards as the earth centred etc also if the starting point(Caucaso) is moving

they go isotropicallly in all inertial frames ( abstracted from air and
ionospheric effects ), but Relativity of simultaneity applies.

The signals received simulataneously in Earth natural frame
were not received simultaneously in ECI frame and vice versa.

> the receiving point (Spain and Mongolia) is moving too and , while the wave is traveling to Spain , this point is coming nearer of around 4 meters and so the travel is shorter like the time ...in Mongolia it happens the contrary ..
> i think that Sagnac has nothing to do here , also ...
>

[Gary Harnagel]

Ahahahaha! The moron speaks, but only idiots believe. Position is a
derivative of coordinates?! "Absolute" coordinates? Check yourself into
the nearest asylum. One the way, stop by the nearest hospital and have
the baloney pumped out of your system.

[Jason Wyome]

( ͡° ͜ʖ ͡°) Gary Harnagel wrote:

> Ahahahaha! The moron speaks, but only idiots believe. Position is a
> derivative of coordinates?! "Absolute" coordinates? Check yourself into

There is no position without coordinates. I can't believe you are so
cretin. Especially in 3d, you need at least 3. (or reduced to 2 depending
on the type of the coordinate system).

> the nearest asylum. One the way, stop by the nearest hospital and have
> the baloney pumped out of your system.

Is this you?

[Maciej Woźniak]

Użytkownik "Gary Harnagel" napisał w wiadomości grup
dyskusyjnych:fbf86fbb-a641-4d02...@googlegroups.com...

On Monday, December 14, 2015 at 6:51:38 AM UTC-7, mlwo...@wp.pl wrote:
>
> W dniu sobota, 12 grudnia 2015 09:51:14 UTC+1 użytkownik Poutnik napisał:
> >
> > But the point is the linear speed is always relative,
> > related to an arbitrary rest.
>
> Only in a relativistic moron's dream.
> In the world we inhabit, speed is a derivative of the position,
> position is a derivative of the coordinates, and sane people
> usually use absolute coordinates.

|Ahahahaha! The moron speaks, but only idiots believe. Position is a
|derivative of coordinates?!

Yes, poor idiot, it is.

| "Absolute" coordinates?

Usually, as stated above.

| Check yourself into
|the nearest asylum. One the way, stop by the nearest hospital and have
|the baloney pumped out of your system.

Usual arguments of a relativistic moron.

[Poutnik]

Dne 14/12/2015 v 17:53 Jason Wyome napsal(a):

> ( ͡° ͜ʖ ͡°) Gary Harnagel wrote:
>
>> Ahahahaha! The moron speaks, but only idiots believe. Position is a
>> derivative of coordinates?! "Absolute" coordinates? Check yourself into
>
> There is no position without coordinates. I can't believe you are so
> cretin. Especially in 3d, you need at least 3. (or reduced to 2 depending
> on the type of the coordinate system).
>

It does not change anything on simple facts
positions is not derivative of coordinates
and coordinates are not absolute.

[mlwo...@wp.pl]

W dniu poniedziałek, 14 grudnia 2015 23:32:24 UTC+1 użytkownik Poutnik napisał:
> Dne 14/12/2015 v 17:53 Jason Wyome napsal(a):
> > ( ͡° ͜ʖ ͡°) Gary Harnagel wrote:
> >
> >> Ahahahaha! The moron speaks, but only idiots believe. Position is a
> >> derivative of coordinates?! "Absolute" coordinates? Check yourself into
> >
> > There is no position without coordinates. I can't believe you are so
> > cretin. Especially in 3d, you need at least 3. (or reduced to 2 depending
> > on the type of the coordinate system).
> >
>
> It does not change anything on simple facts
> positions is not derivative of coordinates

We're speaking English now, not mathematical.

> and coordinates are not absolute.

Coordinates are made for coordination.
They have to be observer independent.
Otherwise, they can't be used for
its MAIN purpose.
Common sense warned your idiot guru,
so he turned it off.

[mlwo...@wp.pl]

W dniu poniedziałek, 14 grudnia 2015 17:53:52 UTC+1 użytkownik Jason Wyome napisał:
> > Ahahahaha! The moron speaks, but only idiots believe. Position is a
> > derivative of coordinates?! "Absolute" coordinates? Check yourself into
>
> There is no position without coordinates. I can't believe you are so
> cretin.

His guru said stupidity has no limits. It's not true
too, but this time error is acceptable.

[nero]

..difficult for me to understand the different positions ..
can we agree about that an e.m. signal arrives earlier in Spain than in Mongolia because the earth is turning from Caucaso to Mongolia ?

[Poutnik]

On 12/15/2015 11:15 AM, nero wrote:
> Il giorno lunedì 14 dicembre 2015 15:17:06 UTC+1, Poutnik ha scritto:
>>> we told that the waves go isotropically as regards as the earth centred etc also if the starting point(Caucaso) is moving
>>
>> they go isotropicallly in all inertial frames ( abstracted from air and
>> ionospheric effects ), but Relativity of simultaneity applies.
>>
>> The signals received simulataneously in Earth natural frame
>> were not received simultaneously in ECI frame and vice versa.
>>
>>> the receiving point (Spain and Mongolia) is moving too and , while the wave is traveling to Spain , this point is coming nearer of around 4 meters and so the travel is shorter like the time ...in Mongolia it happens the contrary ..
>>> i think that Sagnac has nothing to do here , also ...
>>>

> ...difficult for me to understand the different positions ..

> can we agree about that an e.m. signal arrives earlier in Spain than in Mongolia because the earth is turning from Caucaso to Mongolia ?

We should agree that

1/ the signal arrives earlier in Spain than in Mongolia
for a satellite orbitting from east to west
because for it westward light closing speed wrt surface
is faster than eastward one, and vice versa.

2/ We are able to analyse westward and eastward signal wrt Sagnac effect
similarly as it is done in laser ring interferometers
and determine absolute angular ( but not linear ) speed.

--
Poutnik ( the Czech word for a wanderer )

[nero]

...the laser ring interferometer gives the fringes movement ...
then you can translate its directly in angular speed ...
or you can translate its directly in rotational or linear speed (depending to the cases) relationing to the distance of gravitational center ..

[Poutnik]

On 12/16/2015 11:49 AM, nero wrote:
>>
>> We should agree that
>>
>> 1/ the signal arrives earlier in Spain than in Mongolia
>> for a satellite orbitting from east to west
>> because for it westward light closing speed wrt surface
>> is faster than eastward one, and vice versa.
>>
>> 2/ We are able to analyse westward and eastward signal wrt Sagnac effect
>> similarly as it is done in laser ring interferometers
>> and determine absolute angular ( but not linear ) speed.
>>
>>

> ....the laser ring interferometer gives the fringes movement ...

Sure, given by absolute rotation of the device

> then you can translate its directly in angular speed ...

sure

> or you can translate its directly in rotational or linear speed (depending to the cases) relationing to the distance of gravitational center ..

No, you cannot. It relates solely to rotation, not translation.
The linear speed or the rotating point is again
always defined wrt an arbitrary point.

[mlwo...@wp.pl]

W dniu środa, 16 grudnia 2015 12:04:17 UTC+1 użytkownik Poutnik napisał:

> > ....the laser ring interferometer gives the fringes movement ...
>
> Sure, given by absolute rotation of the device

Well, you don't know The Shit well, as expected
from a relativistic moron. There is no "absolute
rotation". It's just a special case of spacetime
curvature.

[nero]

..sure .......'' ..always definited wrt an arbitrary point '' all depending to the evolution of the discussion 'acceleration, a forgotten question ?'

[Poutnik]

Dne 17/12/2015 v 09:52 nero napsal(a):

>
> ...sure .......'' ..always definited wrt an arbitrary point '' all depending to the evolution of the discussion 'acceleration, a forgotten question ?'
>
Or said by a formula

linear velocity of point =

linear velocity of centre of rotation
+ angular velocity x rotation radius // vector product

Speed is then module of linear velocity.

--
Poutnik ( the Czech word for a wanderer )

[Jürgen Großenbach]

Poutnik wrote:

>> ...sure .......'' ..always definited wrt an arbitrary point '' all
>> depending to the evolution of the discussion 'acceleration, a forgotten
>> question ?'
>>
> Or said by a formula linear velocity of point =
> linear velocity of centre of rotation + angular velocity x rotation
> radius // vector product Speed is then module of linear velocity.

( ͡° ͜ʖ ͡°) . You must be meaning *modulus*. But still wrong, you aint
understand any of it. In short what you wrote looks like motion
decomposition in 2d plane. You need to learn material.

[Poutnik]

Dne 17/12/2015 v 21:39 Jürgen Großenbach napsal(a):

Vector product is not defined for 2D space,
what you would know if you understood any of it. :-)

I do not object about modulus,
that is just nitpicking.

[Jürgen Großenbach]

Poutnik wrote:

>>> Or said by a formula linear velocity of point =
>>> linear velocity of centre of rotation + angular velocity x rotation
>>> radius // vector product Speed is then module of linear velocity.
>>
>> ( ͡° ͜ʖ ͡°) . You must be meaning *modulus*. But still wrong, you aint
>> understand any of it. In short what you wrote looks like motion
>> decomposition in 2d plane. You need to learn material.
>
> Vector product is not defined for 2D space, what you would know if you
> understood any of it.

Well not, I must insist. That cross-product (if it was a cross-product)
takes input a two vector in 2d, then outputs an orthogonal to both. Be it
outside the plane, 3d if you wish. But it was not your intention.

[Poutnik]

Dne 17/12/2015 v 21:58 Jürgen Großenbach napsal(a):

What was my intention ? I am curious.

[Jürgen Großenbach]

Poutnik wrote:

>>>>> Or said by a formula linear velocity of point =
>>>>> linear velocity of centre of rotation + angular velocity x rotation
>>>>> radius // vector product Speed is then module of linear velocity.
>>>>
>>>> ( ͡° ͜ʖ ͡°) . You must be meaning *modulus*. But still wrong, you
>>>> aint understand any of it. In short what you wrote looks like motion
>>>> decomposition in 2d plane. You need to learn material.
>>>
>>> Vector product is not defined for 2D space, what you would know if you
>>> understood any of it.
>>
>> Well not, I must insist. That cross-product (if it was a cross-product)
>> takes input a two vector in 2d, then outputs an orthogonal to both. Be
>> it outside the plane, 3d if you wish. But it was not your intention.
>
> What was my intention ? I am curious.

"linear velocity of point". A point cannot rotate. Got it? In fact there
is not much difference between speed and velocity. But rather among
Translation and Rotation. This is what is primordial in Physics.
https://en.wikipedia.org/wiki/File:Cross_product_vector.svg

[Sam Wormley]

On 12/17/15 3:53 PM, Jürgen Großenbach wrote:
> A point cannot rotate.


Since a decreasing circle centered on the south pole rotate .. as it
gets smaller and small continues to rotate until it is a point
rotation.

--

sci.physics is an unmoderated newsgroup dedicated
to the discussion of physics, news from the physics
community, and physics-related social issues.

[Jürgen Großenbach]

Sam Wormley wrote:

> On 12/17/15 3:53 PM, Jürgen Großenbach wrote:
>> A point cannot rotate.
>
> Since a decreasing circle centered on the south pole rotate .. as it
> gets smaller and small continues to rotate until it is a point
> rotation.

Amazing, fabulous. Neither points or circles can possibly rotate. You
think like an amoeba.

[Poutnik]

Dne 17/12/2015 v 22:53 Jürgen Großenbach napsal(a):

Linear and angular velocity of point.

Of course the point can rotate.
I did not say it is around its axis.

Electrons have spin and orbital angular momentum,
represented by their spin and magnetic quantum numbers.

Velocity is vector, speed is scalar.
Both can be linear and angular.

--
Poutnik ( the Czech word for a wanderer )

[Jürgen Großenbach]

Poutnik wrote:

>> "linear velocity of point". A point cannot rotate. Got it? In fact
>> there is not much difference between speed and velocity. But rather
>> among Translation and Rotation. This is what is primordial in Physics.
>> https://en.wikipedia.org/wiki/File:Cross_product_vector.svg
>>
> Linear and angular velocity of point. Of course the point can rotate.

Man, you are intolerable stupid. Talk to your finger from now on.

[Sam Wormley]

<smiling>

[Jürgen Großenbach]

Sam Wormley wrote:

> On 12/17/15 5:06 PM, Jürgen Großenbach wrote:
>> Poutnik wrote:
>>
>>>> "linear velocity of point". A point cannot rotate. Got it? In fact
>>>> there is not much difference between speed and velocity. But rather
>>>> among Translation and Rotation. This is what is primordial in
>>>> Physics.
>>>> https://en.wikipedia.org/wiki/File:Cross_product_vector.svg
>>>>
>>> Linear and angular velocity of point. Of course the point can rotate.
>>
>> Man, you are intolerable stupid. Talk to your finger from now on.
>
> <smiling>

He is talkin about translation along a curved path. What do you think?
Still rotating your circle?