Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics.relativity > #617120 > unrolled thread

Relativistic rotating disc

Back to article view | Back to sci.physics.relativity

Contents

  Relativistic rotating disc Richard Hachel <r.hachel@frite.fr> - 2023-08-08 16:24 +0000
    Re: Relativistic rotating disc "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2023-08-08 10:59 -0700
    Re: Relativistic rotating disc JanPB <filmart@gmail.com> - 2023-08-08 13:45 -0700
      Re: Relativistic rotating disc Richard Hachel <r.hachel@frite.fr> - 2023-08-08 21:02 +0000
        Re: Relativistic rotating disc "mitchr...@gmail.com" <mitchrae3323@gmail.com> - 2023-08-08 17:09 -0700
        Re: Relativistic rotating disc Maciej Wozniak <maluwozniak@gmail.com> - 2023-08-08 21:38 -0700
        Re: Relativistic rotating disc JanPB <filmart@gmail.com> - 2023-08-08 22:28 -0700
          Re: Relativistic rotating disc Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-08-08 22:39 -0700
            Re: Relativistic rotating disc Ross Finlayson <ross.a.finlayson@gmail.com> - 2023-08-09 19:13 -0700
    Re: Relativistic rotating disc Sylvia Else <sylvia@email.invalid> - 2023-08-09 19:12 +1000
      Re: Relativistic rotating disc Richard Hachel <r.hachel@frite.fr> - 2023-08-09 12:27 +0000
        Re: Relativistic rotating disc Sylvia Else <sylvia@email.invalid> - 2023-08-09 22:39 +1000
          Re: Relativistic rotating disc Richard Hachel <r.hachel@frite.fr> - 2023-08-09 12:52 +0000
        Re: Relativistic rotating disc Athel Cornish-Bowden <athel.cb@gmail.com> - 2023-08-09 19:14 +0200
          Re: Relativistic rotating disc Richard Hachel <r.hachel@frite.fr> - 2023-08-09 17:35 +0000

#617120 — Relativistic rotating disc

Relativistic rotating disc.

We talk about that very little, and as a specialist in relativistic 
kinematics, I understand very well why.

It's not easy to talk about that.

Some may even have fits of terror, it's so complicated.

The solution requires small baby steps.

Very important the small steps of babies in relativity.

Fundamental, even.

R.H. 

[toc] | [next] | [standalone]

#617130

On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote:
> Relativistic rotating disc. 
> 
> We talk about that very little, and as a specialist in relativistic 
> kinematics, I understand very well why. 
> 
> It's not easy to talk about that. 
> 
> Some may even have fits of terror, it's so complicated. 
> 
> The solution requires small baby steps. 
> 
> Very important the small steps of babies in relativity. 
> 
> Fundamental, even. 
> 
> R.H.

Rotation motion speed only manifests at the very slow turning in space.
There is no example of it getting very high yet alone near light speed.
Because it manifests only slow in the universe. Its time dilation remains
low and its kinetic energy remains low the same.

What could push rotation to near light speed?

[toc] | [prev] | [next] | [standalone]

#617147

On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote:
> Relativistic rotating disc. 
> 
> We talk about that very little, and as a specialist in relativistic 
> kinematics, I understand very well why. 
> 
> It's not easy to talk about that. 
> 
> Some may even have fits of terror, it's so complicated. 
> 
> The solution requires small baby steps. 
> 
> Very important the small steps of babies in relativity. 
> 
> Fundamental, even. 
> 
> R.H.

It's for the same reason Newtonian mechanics using accelerated observers
is not as commonly discussed, it requires a decent command of at least
vector calculus and some linear algebra. The added complication in
the case of special relativity is that the time variable is related to proper
time by a function (not the identity function). Other than that there is nothing
terribly exotic in it, theoretically speaing.

--
Jan

[toc] | [prev] | [next] | [standalone]

#617148

Le 08/08/2023 à 22:45, JanPB a écrit :
> On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote:
>> Relativistic rotating disc. 
>> 
>> We talk about that very little, and as a specialist in relativistic 
>> kinematics, I understand very well why. 
>> 
>> It's not easy to talk about that. 
>> 
>> Some may even have fits of terror, it's so complicated. 
>> 
>> The solution requires small baby steps. 
>> 
>> Very important the small steps of babies in relativity. 
>> 
>> Fundamental, even. 
>> 
>> R.H.
> 
> It's for the same reason Newtonian mechanics using accelerated observers
> is not as commonly discussed, it requires a decent command of at least
> vector calculus and some linear algebra. The added complication in
> the case of special relativity is that the time variable is related to proper
> time by a function (not the identity function). Other than that there is nothing
> terribly exotic in it, theoretically speaing.
> 
> --
> Jan

The relativistic spinning disc poses an obvious problem, just as 
Langevin's traveler poses an obvious problem.

The obvious problem, in Langevin's traveler, is not the fact that there is 
a paradox in the reciprocal positive chronotropy of the two protagonists 
(that is to say that the INTERNAL mechanism of their watch beats 
constantly faster that the other shows, which may seem absurd in the end), 
is that there is a total blindness of physicists on the clear description 
of the phenomenon, and a total ignorance of the covariance of the apparent 
reciprocal relativistic effects.

But I talked about that, and if it can make the idiots laugh who don't 
understand what I'm saying, let them laugh!

The other problem, that of the spinning disc, is that physicists agree 
that the time at the periphery expands, that the circumference contracts, 
but that they do not understand anything at all of what is happening. for 
the radius, considered invariant.
We then enter a kind of madness, with a space in the shape of a horse 
saddle and other fun things.

However, if we apply the invariance of the speed of light, as we do for 
the Poincaré-Lorentz transformations, we realize that there will also be, 
progressively, as the disk rotates, a similar contraction of the radius, 
so that if the circumference becomes C'=C.sqrt(1-v²/c²) where c is the 
tangential velocity,
the radius undergoes the same thing, and "pi" remains constant.

I talked about this on a post of the day on fr.sci.physics

Those who speak French can go and read.

The calculations are simple and the concept obvious, starting from the 
invariant speed of light.

Doctor Richard Hachel 

[toc] | [prev] | [next] | [standalone]

#617150

On Tuesday, August 8, 2023 at 2:02:07 PM UTC-7, Richard Hachel wrote:
> Le 08/08/2023 à 22:45, JanPB a écrit : 
> > On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote: 
> >> Relativistic rotating disc. 
> >> 
> >> We talk about that very little, and as a specialist in relativistic 
> >> kinematics, I understand very well why. 
> >> 
> >> It's not easy to talk about that. 
> >> 
> >> Some may even have fits of terror, it's so complicated. 
> >> 
> >> The solution requires small baby steps. 
> >> 
> >> Very important the small steps of babies in relativity. 
> >> 
> >> Fundamental, even. 
> >> 
> >> R.H. 
> > 
> > It's for the same reason Newtonian mechanics using accelerated observers 
> > is not as commonly discussed, it requires a decent command of at least 
> > vector calculus and some linear algebra. The added complication in 
> > the case of special relativity is that the time variable is related to proper 
> > time by a function (not the identity function). Other than that there is nothing 
> > terribly exotic in it, theoretically speaing. 
> > 
> > -- 
> > Jan
> The relativistic spinning disc poses an obvious problem, just as 
> Langevin's traveler poses an obvious problem. 
> 
> The obvious problem, in Langevin's traveler, is not the fact that there is 
> a paradox in the reciprocal positive chronotropy of the two protagonists 
> (that is to say that the INTERNAL mechanism of their watch beats 
> constantly faster that the other shows, which may seem absurd in the end), 
> is that there is a total blindness of physicists on the clear description 
> of the phenomenon, and a total ignorance of the covariance of the apparent 
> reciprocal relativistic effects. 
> 
> But I talked about that, and if it can make the idiots laugh who don't 
> understand what I'm saying, let them laugh! 
> 
> The other problem, that of the spinning disc, is that physicists agree 
> that the time at the periphery expands, that the circumference contracts, 
> but that they do not understand anything at all of what is happening. for 
> the radius, considered invariant. 
> We then enter a kind of madness, with a space in the shape of a horse 
> saddle and other fun things. 
> 
> However, if we apply the invariance of the speed of light, as we do for 
> the Poincaré-Lorentz transformations, we realize that there will also be, 
> progressively, as the disk rotates, a similar contraction of the radius, 
> so that if the circumference becomes C'=C.sqrt(1-v²/c²) where c is the 
> tangential velocity, 
> the radius undergoes the same thing, and "pi" remains constant. 
> 
> I talked about this on a post of the day on fr.sci.physics 
> 
> Those who speak French can go and read. 
> 
> The calculations are simple and the concept obvious, starting from the 
> invariant speed of light. 
> 
> Doctor Richard Hachel


Curvilinear speed or propulsion can approach near light speed in some manifestations.
Such as a space ship.

but the round motion of rotation does not. It stays manifesting only at its low side.
What are the fastest rotating objects? They would be the practical limit in the universe
forever. Fast spin is still from a low rotation moving through a tight spiral space
that is always a smaller radius.


Mitchell Raemsch

[toc] | [prev] | [next] | [standalone]

#617154

On Tuesday, 8 August 2023 at 23:02:07 UTC+2, Richard Hachel wrote:
> Le 08/08/2023 à 22:45, JanPB a écrit : 
> > On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote: 
> >> Relativistic rotating disc. 
> >> 
> >> We talk about that very little, and as a specialist in relativistic 
> >> kinematics, I understand very well why. 
> >> 
> >> It's not easy to talk about that. 
> >> 
> >> Some may even have fits of terror, it's so complicated. 
> >> 
> >> The solution requires small baby steps. 
> >> 
> >> Very important the small steps of babies in relativity. 
> >> 
> >> Fundamental, even. 
> >> 
> >> R.H. 
> > 
> > It's for the same reason Newtonian mechanics using accelerated observers 
> > is not as commonly discussed, it requires a decent command of at least 
> > vector calculus and some linear algebra. The added complication in 
> > the case of special relativity is that the time variable is related to proper 
> > time by a function (not the identity function). Other than that there is nothing 
> > terribly exotic in it, theoretically speaing. 
> > 
> > -- 
> > Jan
> The relativistic spinning disc poses an obvious problem, just as 
> Langevin's traveler poses an obvious problem. 
> 
> The obvious problem, in Langevin's traveler, is not the fact that there is 
> a paradox in the reciprocal positive chronotropy of the two protagonists 
> (that is to say that the INTERNAL mechanism of their watch beats 
> constantly faster that the other shows, which may seem absurd in the end), 
> is that there is a total blindness of physicists on the clear description 
> of the phenomenon, and a total ignorance of the covariance of the apparent 
> reciprocal relativistic effects. 

And in the meantime in the real world, forbidden by worshippers
of Giant Guru improper clocks keep measuring t'=t, just like all serious
clocks always did.

[toc] | [prev] | [next] | [standalone]

#617158

On Tuesday, August 8, 2023 at 2:02:07 PM UTC-7, Richard Hachel wrote:
> Le 08/08/2023 à 22:45, JanPB a écrit : 
> > On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote: 
> >> Relativistic rotating disc. 
> >> 
> >> We talk about that very little, and as a specialist in relativistic 
> >> kinematics, I understand very well why. 
> >> 
> >> It's not easy to talk about that. 
> >> 
> >> Some may even have fits of terror, it's so complicated. 
> >> 
> >> The solution requires small baby steps. 
> >> 
> >> Very important the small steps of babies in relativity. 
> >> 
> >> Fundamental, even. 
> >> 
> >> R.H. 
> > 
> > It's for the same reason Newtonian mechanics using accelerated observers 
> > is not as commonly discussed, it requires a decent command of at least 
> > vector calculus and some linear algebra. The added complication in 
> > the case of special relativity is that the time variable is related to proper 
> > time by a function (not the identity function). Other than that there is nothing 
> > terribly exotic in it, theoretically speaing. 
> > 
> > -- 
> > Jan
> The relativistic spinning disc poses an obvious problem, just as 
> Langevin's traveler poses an obvious problem. 
> 
> The obvious problem, in Langevin's traveler, is not the fact that there is 
> a paradox in the reciprocal positive chronotropy 

Stop using private secret terminology.

> of the two protagonists 
> (that is to say that the INTERNAL mechanism of their watch beats 
> constantly faster that the other shows, 

This is just poetry.

> which may seem absurd in the end), 

It seems neither. You stated something with no meaning in physics.

> is that there is a total blindness of physicists on the clear description 
> of the phenomenon, and a total ignorance of the covariance of the apparent 
> reciprocal relativistic effects. 

No, you just don't understand this. You need to understand first what it
is that you are trying to analyse.

--
Jan

[toc] | [prev] | [next] | [standalone]

#617159

On Tuesday, August 8, 2023 at 10:28:31 PM UTC-7, JanPB wrote:
> On Tuesday, August 8, 2023 at 2:02:07 PM UTC-7, Richard Hachel wrote:
> > Le 08/08/2023 à 22:45, JanPB a écrit : 
> > > On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote: 
> > >> Relativistic rotating disc. 
> > >> 
> > >> We talk about that very little, and as a specialist in relativistic 
> > >> kinematics, I understand very well why. 
> > >> 
> > >> It's not easy to talk about that. 
> > >> 
> > >> Some may even have fits of terror, it's so complicated. 
> > >> 
> > >> The solution requires small baby steps. 
> > >> 
> > >> Very important the small steps of babies in relativity. 
> > >> 
> > >> Fundamental, even. 
> > >> 
> > >> R.H. 
> > > 
> > > It's for the same reason Newtonian mechanics using accelerated observers 
> > > is not as commonly discussed, it requires a decent command of at least 
> > > vector calculus and some linear algebra. The added complication in 
> > > the case of special relativity is that the time variable is related to proper 
> > > time by a function (not the identity function). Other than that there is nothing 
> > > terribly exotic in it, theoretically speaing. 
> > > 
> > > -- 
> > > Jan 
> > The relativistic spinning disc poses an obvious problem, just as 
> > Langevin's traveler poses an obvious problem. 
> > 
> > The obvious problem, in Langevin's traveler, is not the fact that there is 
> > a paradox in the reciprocal positive chronotropy
> Stop using private secret terminology.
> > of the two protagonists 
> > (that is to say that the INTERNAL mechanism of their watch beats 
> > constantly faster that the other shows,
> This is just poetry.
> > which may seem absurd in the end),
> It seems neither. You stated something with no meaning in physics.
> > is that there is a total blindness of physicists on the clear description 
> > of the phenomenon, and a total ignorance of the covariance of the apparent 
> > reciprocal relativistic effects.
> No, you just don't understand this. You need to understand first what it 
> is that you are trying to analyse. 
> 
> -- 
> Jan

How about [0,1]?

Poesis and Mathesis are two different things, but they might be the same.

Sagnac and Ehrenfest and the rotating disc, make for that the ring laser gyro 
is a functional apparatus, while the three-phase motor is an astable configuration, 
then about for example Jefimenko and "whither effect".

(I'd rather not guilt-by-associate with trolls but neither is it their medium.)

[toc] | [prev] | [next] | [standalone]

#617238

On Tuesday, August 8, 2023 at 10:39:43 PM UTC-7, Ross Finlayson wrote:
> On Tuesday, August 8, 2023 at 10:28:31 PM UTC-7, JanPB wrote: 
> > On Tuesday, August 8, 2023 at 2:02:07 PM UTC-7, Richard Hachel wrote: 
> > > Le 08/08/2023 à 22:45, JanPB a écrit : 
> > > > On Tuesday, August 8, 2023 at 9:24:47 AM UTC-7, Richard Hachel wrote: 
> > > >> Relativistic rotating disc. 
> > > >> 
> > > >> We talk about that very little, and as a specialist in relativistic 
> > > >> kinematics, I understand very well why. 
> > > >> 
> > > >> It's not easy to talk about that. 
> > > >> 
> > > >> Some may even have fits of terror, it's so complicated. 
> > > >> 
> > > >> The solution requires small baby steps. 
> > > >> 
> > > >> Very important the small steps of babies in relativity. 
> > > >> 
> > > >> Fundamental, even. 
> > > >> 
> > > >> R.H. 
> > > > 
> > > > It's for the same reason Newtonian mechanics using accelerated observers 
> > > > is not as commonly discussed, it requires a decent command of at least 
> > > > vector calculus and some linear algebra. The added complication in 
> > > > the case of special relativity is that the time variable is related to proper 
> > > > time by a function (not the identity function). Other than that there is nothing 
> > > > terribly exotic in it, theoretically speaing. 
> > > > 
> > > > -- 
> > > > Jan 
> > > The relativistic spinning disc poses an obvious problem, just as 
> > > Langevin's traveler poses an obvious problem. 
> > > 
> > > The obvious problem, in Langevin's traveler, is not the fact that there is 
> > > a paradox in the reciprocal positive chronotropy 
> > Stop using private secret terminology. 
> > > of the two protagonists 
> > > (that is to say that the INTERNAL mechanism of their watch beats 
> > > constantly faster that the other shows, 
> > This is just poetry. 
> > > which may seem absurd in the end), 
> > It seems neither. You stated something with no meaning in physics. 
> > > is that there is a total blindness of physicists on the clear description 
> > > of the phenomenon, and a total ignorance of the covariance of the apparent 
> > > reciprocal relativistic effects. 
> > No, you just don't understand this. You need to understand first what it 
> > is that you are trying to analyse. 
> > 
> > -- 
> > Jan
> How about [0,1]? 
> 
> Poesis and Mathesis are two different things, but they might be the same. 
> 
> Sagnac and Ehrenfest and the rotating disc, make for that the ring laser gyro 
> is a functional apparatus, while the three-phase motor is an astable configuration, 
> then about for example Jefimenko and "whither effect". 
> 
> (I'd rather not guilt-by-associate with trolls but neither is it their medium.)

Yeah, when it comes to the relativistic rotating disc, 
there's Sagnac, Ehrenfest, and Jefimenko, and especially 
for Sagnac, that a ring gyro implements an accelerometer.

Similarly, but, you know, different, for the atomic clock lattice, 
therre are lots of solid state components already sort of employing 
these effects.


About [0,1] it was to the question "what is analysis", and about that 
mathematics sort of has a standard defintion of the complete ordered 
field, but, it's arrived at there are other definitions of continuity, the 
completeness of continuity or least-upper-bound property, and also 
for measure and measure theory.  For things like path elements and 
line elements, for example, of the path integral, and Jordan measure, 
which in physics is a thing but in formal mathematics is estranged, 
and also the Dirichlet problem, anything about a metrizing ultrafilter 
according to topology that is either line elements (infinitesimals of 
a line the length of which is one) or "the everywhere discontinuous" 
(which has yet analytical character), it's that mathematics sort of 
owes physics better and more, and consistent, fundamental formalisms 
of continuity.  Then, some modern category theories basically have [0,1] 
as a primary sort of object, which is sensible, which of course you can 
read for yourself from ncatlab and so on, that "Aristotle's Jordan's continuum 
and Eudoxus's Cauchy's Dedekind's continuum and Dirichlet's Nyquist's 
Shannon's continuum, are three things the same thing, Du Bois-Reymond's.

Then, the gyroscope and for example the nanogyroscope, and conversion 
of energy to "rotational momentum" but not "linear momentum", except 
at the ring, but not for the space, it's really a thing that the rotational and 
the linear are sort of different with respect to mass-energy equivalency.

[toc] | [prev] | [next] | [standalone]

#617164

On 09-Aug-23 2:24 am, Richard Hachel wrote:
> Relativistic rotating disc.
> 
> We talk about that very little, and as a specialist in relativistic 
> kinematics, I understand very well why.
> 
> It's not easy to talk about that.
> 
> Some may even have fits of terror, it's so complicated.
> 
> The solution requires small baby steps.
> 
> Very important the small steps of babies in relativity.
> 
> Fundamental, even.
> 
> R.H.

Take a rotating disk whose centre is not moving. Consider a point on the 
disk and express the variation of its coordinates with time in terms of 
the coordinates of the centre of the disk.

Now use the Lorentz transform to transform the coordinates of the point 
on the disk into some desired frame in motion relative to the centre of 
the disk.

Job done.

Sylvia.

[toc] | [prev] | [next] | [standalone]

#617172

Le 09/08/2023 à 11:12, Sylvia Else a écrit :
> Take a rotating disk whose centre is not moving. Consider a point on the 
> disk and express the variation of its coordinates with time in terms of 
> the coordinates of the centre of the disk.
> 
> Now use the Lorentz transform to transform the coordinates of the point 
> on the disk into some desired frame in motion relative to the centre of 
> the disk.
> 
> Job done.
> 
> Sylvia.

My love Sylvia.
I really like the very simple and very pure way in which you say things.
It is true and important to note that the center of the rotating disc does 
not move. This means that if the periphery of the disc is constantly 
changing, and creates its own reference frame (like each point on the 
disc), the center remains in the R reference frame of the lab.

You say that it is then necessary to apply the Lorentz transformations, 
but the Lorentz transformations apply to the Galilean frames of reference 
and not to the rotating frames of reference.

It's not that they are false if we do that, it's that the rotating 
reference frame, as it accelerates, takes on absolute properties, and 
deformations appear there.

But we'll talk about that again, because it's both very simple (once you 
have all the transformation equations) and very complicated as long as you 
don't have them all.

So no, the Lorentz transformations don't work for this specific case, 
there are deformations while the disk starts accelerating, and it's not 
the same disk as at the start in R. first convert the disk from R1 
(resting in R) to R2 (spinning in R) and only later apply the TLs.

R.H.

[toc] | [prev] | [next] | [standalone]

#617174

On 09-Aug-23 10:27 pm, Richard Hachel wrote:
> Le 09/08/2023 à 11:12, Sylvia Else a écrit :
>> Take a rotating disk whose centre is not moving. Consider a point on 
>> the disk and express the variation of its coordinates with time in 
>> terms of the coordinates of the centre of the disk.
>>
>> Now use the Lorentz transform to transform the coordinates of the 
>> point on the disk into some desired frame in motion relative to the 
>> centre of the disk.
>>
>> Job done.
>>
>> Sylvia.
> 
> My love Sylvia.
> I really like the very simple and very pure way in which you say things.
> It is true and important to note that the center of the rotating disc 
> does not move. This means that if the periphery of the disc is 
> constantly changing, and creates its own reference frame (like each 
> point on the disc), the center remains in the R reference frame of the lab.
> 
> You say that it is then necessary to apply the Lorentz transformations, 
> but the Lorentz transformations apply to the Galilean frames of 
> reference and not to the rotating frames of reference.
> 
> It's not that they are false if we do that, it's that the rotating 
> reference frame, as it accelerates, takes on absolute properties, and 
> deformations appear there.
> 
> But we'll talk about that again, because it's both very simple (once you 
> have all the transformation equations) and very complicated as long as 
> you don't have them all.
> 
> So no, the Lorentz transformations don't work for this specific case, 
> there are deformations while the disk starts accelerating, and it's not 
> the same disk as at the start in R. first convert the disk from R1 
> (resting in R) to R2 (spinning in R) and only later apply the TLs.
> 
> R.H.

You're overcomplicating things. A point is just a point. It has a set of 
coordinates, including time. It cannot be said to be moving, much less 
accelerating, because both of those involve more than one time, and a 
point only has one time coordinate.

Sylvia.

[toc] | [prev] | [next] | [standalone]

#617175

Le 09/08/2023 à 14:39, Sylvia Else a écrit :
> On 09-Aug-23 10:27 pm, Richard Hachel wrote:
>> Le 09/08/2023 à 11:12, Sylvia Else a écrit :
>>> Take a rotating disk whose centre is not moving. Consider a point on 
>>> the disk and express the variation of its coordinates with time in 
>>> terms of the coordinates of the centre of the disk.
>>>
>>> Now use the Lorentz transform to transform the coordinates of the 
>>> point on the disk into some desired frame in motion relative to the 
>>> centre of the disk.
>>>
>>> Job done.
>>>
>>> Sylvia.
>> 
>> My love Sylvia.
>> I really like the very simple and very pure way in which you say things.
>> It is true and important to note that the center of the rotating disc 
>> does not move. This means that if the periphery of the disc is 
>> constantly changing, and creates its own reference frame (like each 
>> point on the disc), the center remains in the R reference frame of the lab.
>> 
>> You say that it is then necessary to apply the Lorentz transformations, 
>> but the Lorentz transformations apply to the Galilean frames of 
>> reference and not to the rotating frames of reference.
>> 
>> It's not that they are false if we do that, it's that the rotating 
>> reference frame, as it accelerates, takes on absolute properties, and 
>> deformations appear there.
>> 
>> But we'll talk about that again, because it's both very simple (once you 
>> have all the transformation equations) and very complicated as long as 
>> you don't have them all.
>> 
>> So no, the Lorentz transformations don't work for this specific case, 
>> there are deformations while the disk starts accelerating, and it's not 
>> the same disk as at the start in R. first convert the disk from R1 
>> (resting in R) to R2 (spinning in R) and only later apply the TLs.
>> 
>> R.H.
> 
> You're overcomplicating things. A point is just a point. It has a set of 
> coordinates, including time. It cannot be said to be moving, much less 
> accelerating, because both of those involve more than one time, and a 
> point only has one time coordinate.
> 
> Sylvia.

I like when you defend yourself like that.

R.H. 

[toc] | [prev] | [next] | [standalone]

#617198

On 2023-08-09 12:27:33 +0000, "Dr." Richard Hachel said:

> Le 09/08/2023 à 11:12, Sylvia Else a écrit :
>> Take a rotating disk whose centre is not moving. Consider a point on 
>> the disk and express the variation of its coordinates with time in 
>> terms of the coordinates of the centre of the disk.
>> 
>> Now use the Lorentz transform to transform the coordinates of the point 
>> on the disk into some desired frame in motion relative to the centre of 
>> the disk.
>> 
>> Job done.
>> 
>> Sylvia.
> 
> My love Sylvia.

There are many things that irritate me about you, "Dr." Hachel, and 
this mansplaining you do with Sylvia is one of them.

> I really like the very simple and very pure way in which you say things.
> It is true and important to note that the center of the rotating disc 
> does not move. This means that if the periphery of the disc is 
> constantly changing, and creates its own reference frame (like each 
> point on the disc), the center remains in the R reference frame of the 
> lab.
> 
> You say that it is then necessary to apply the Lorentz transformations, 
> but the Lorentz transformations apply to the Galilean frames of 
> reference and not to the rotating frames of reference.
> 
> It's not that they are false if we do that, it's that the rotating 
> reference frame, as it accelerates, takes on absolute properties, and 
> deformations appear there.
> 
> But we'll talk about that again, because it's both very simple (once 
> you have all the transformation equations) and very complicated as long 
> as you don't have them all.
> 
> So no, the Lorentz transformations don't work for this specific case, 
> there are deformations while the disk starts accelerating, and it's not 
> the same disk as at the start in R. first convert the disk from R1 
> (resting in R) to R2 (spinning in R) and only later apply the TLs.
> 
> R.H.


-- 
athel -- biochemist, not a physicist, but detector of crackpots

[toc] | [prev] | [next] | [standalone]

#617202

Le 09/08/2023 à 19:14, Athel Cornish-Bowden a écrit :

> There are many things that irritate me about you, "Dr." Hachel, and 
> this mansplaining you do with Sylvia is one of them.

 
The term "mansplaining" is not appropriate.
And then you have to leave Sylvia, she's big enough to defend herself.

R.H. 

[toc] | [prev] | [standalone]

Back to top | Article view | sci.physics.relativity

csiph-web