1. If two observers, at rest with respect to each other, synchronize
all their clocks and rulers with each other, the two individual sets
of clocks and rulers will remain synchronized among themselves even
after the two observers are in uniform motion with respect to each
other.

2. If two points are at rest with respect to one observer who measures
their distance apart as d, and lie on a line perpendicular to the
direction of motion with a second observer, the latter observer also
observes the points being of distance apart d and perpendicular to the
direction of motion.

I am not 100% sure that the constancy of the speed of light assumption
can be weakened to:
3. If observer 1 measures the speed of light between a source and
target that are both at rest with respect to observer 1, then observer
2 in uniform motion with respect to 1, will also measure the same
speed of light between the same source and target.

On Thursday, September 30, 2021 at 9:39:15 AM UTC-7, Ricardo Jimenez wrote:
> More Unstated Special Relativity Axioms

The word "more" is immediately wrong, because your previous claim about reciprocity was debunked. Reciprocity is implied by the combination of the principle of relativity and isotropy.

> 1. If two observers, at rest with respect to each other, synchronize
> all their clocks and rulers with each other...

Rulers are not synchronized. Synchronization refers to the time coordinate..

> the two individual sets of clocks and rulers will remain synchronized among
> themselves even after the two observers are in uniform motion with respect
> to each other.

That is false.

> 2. If two points are at rest with respect to one observer who measures
> their distance apart as d, and lie on a line perpendicular to the
> direction of motion with a second observer, the latter observer also
> observes the points being of distance apart d and perpendicular to the
> direction of motion.

That is not an unstated axiom, it is specifically addressed in Einstein's 1905 paper (for example) based on isotropy, etc., and even (less satisfactorily) in Lorentz's 1904 paper.

> I am not 100% sure that the constancy of the speed of light assumption
> can be weakened to:
> 3. If observer 1 measures the speed of light between a source and
> target that are both at rest with respect to observer 1, then observer
> 2 in uniform motion with respect to 1, will also measure the same
> speed of light between the same source and target.

That's garbled, since it doesn't define what it means to "measure a speed". A correct statement refers to specified systems of coordinates, as in Einstein's 1905 paper. That paper just asserts invariant light speed in vacuum in terms of one particular system of inertial coordinates, and then combines this with the relativity principle (and tacit assumption of no efficacious ether) to assert that it has the same invariant value in terms of every system of inertial coordinates.

On Thursday, 30 September 2021 at 18:54:53 UTC+2, Townes Olson wrote:

> That's garbled, since it doesn't define what it means to "measure a speed". A correct statement refers to specified systems of coordinates, as in Einstein's 1905 paper.

In the meantime in the real world, however, GPS clocks
keep indicating t'=t, just like all serious clocks always did.

On Thursday, September 30, 2021 at 10:48:03 AM UTC-7, maluw...@gmail.com wrote:
> On Thursday, 30 September 2021 at 18:54:53 UTC+2, Townes Olson wrote:
>
> > That's garbled, since it doesn't define what it means to "measure a speed". A correct statement refers to specified systems of coordinates, as in Einstein's 1905 paper.
> In the meantime in the real world, however, GPS clocks
> keep indicating t'=t, just like all serious clocks always did.

Maciej, not where there are space eddies as about relativistic effects, no.

When we point to the Parameterized Post Newtonian as most accurate,
simply don't be forgetting that it's not just "Newtonian".

On Thu, 30 Sep 2021 09:54:51 -0700 (PDT), Townes Olson
<townesolson7@gmail.com> wrote:

>On Thursday, September 30, 2021 at 9:39:15 AM UTC-7, Ricardo Jimenez wrote:
>> More Unstated Special Relativity Axioms
>
>The word "more" is immediately wrong, because your previous claim about reciprocity was debunked. Reciprocity is implied by the combination of the principle of relativity and isotropy.
>
It most certainly was not.

>> 1. If two observers, at rest with respect to each other, synchronize
>> all their clocks and rulers with each other...
>
>Rulers are not synchronized. Synchronization refers to the time coordinate.
>
I don't know the word to use to say the rulers are matched. So I
abused language a bit. The meaning is clear

>> the two individual sets of clocks and rulers will remain synchronized among
>> themselves even after the two observers are in uniform motion with respect
>> to each other.
>
>That is false.
? Because you say so?
>
>> 2. If two points are at rest with respect to one observer who measures
>> their distance apart as d, and lie on a line perpendicular to the
>> direction of motion with a second observer, the latter observer also
>> observes the points being of distance apart d and perpendicular to the
>> direction of motion.
>
>That is not an unstated axiom, it is specifically addressed in Einstein's 1905 paper (for example) based on isotropy, etc., and even (less satisfactorily) in Lorentz's 1904 paper.
>
You are just doing some unhelpful hand waving.

>> I am not 100% sure that the constancy of the speed of light assumption
>> can be weakened to:
>> 3. If observer 1 measures the speed of light between a source and
>> target that are both at rest with respect to observer 1, then observer
>> 2 in uniform motion with respect to 1, will also measure the same
>> speed of light between the same source and target.
>
>That's garbled, since it doesn't define what it means to "measure a speed". A correct statement refers to specified systems of coordinates, as in Einstein's 1905 paper. That paper just asserts invariant light speed in vacuum in terms of one particular system of inertial coordinates, and then combines this with the relativity principle (and tacit assumption of no efficacious ether) to assert that it has the same invariant value in terms of every system of inertial coordinates.

You measure the distance between the source and receiver of the light
and then measure the time elapsed and then divide the two. Special
relativity is all about making those measurements in reference frames
in relative motion to each other.

On Friday, October 1, 2021 at 10:23:13 AM UTC-7, Ricardo Jimenez wrote:
> >> More Unstated Special Relativity Axioms
> >The word "more" is immediately wrong, because your previous claim about
> > reciprocity was debunked. Reciprocity is implied by the combination of the
> > principle of relativity and isotropy.
> >
> It most certainly was not.

It was. See the other thread, in which your misconception about reciprocity was thoroughly debunked.

> >> 1. If two observers, at rest with respect to each other, synchronize
> >> all their clocks and rulers with each other...
> >
> >Rulers are not synchronized. Synchronization refers to the time coordinate.
> >
> I don't know the word to use to say the rulers are matched. So I
> abused language a bit. The meaning is clear

The meaning is not clear. It is gibberish. Again, rulers are not synchronized. Synchronization refer to the time coordinate. Saying that the rulers are "matched" is also not clear. What does it mean to "match" rulers?

> >> the two individual sets of clocks and rulers will remain synchronized among
> >> themselves even after the two observers are in uniform motion with respect
> >> to each other.
> >
> >That is false.
>
> ? Because you say so?

No, it was already false before I said it, and it would be false even if I never said it. Clocks obviously do not remain synchronized (in terms of any given system of inertial coordinates) if they are placed into different states of motion relative to each other. In fact, they don't even remain synchronized (in terms of their own inertial rest coordinates) if they are put into the same state of motion different from the first. This is Relativity 101.

> >> 2. If two points are at rest with respect to one observer who measures
> >> their distance apart as d, and lie on a line perpendicular to the
> >> direction of motion with a second observer, the latter observer also
> >> observes the points being of distance apart d and perpendicular to the
> >> direction of motion.
> >
> >That is not an unstated axiom, it is specifically addressed in Einstein's 1905 paper (for example) based on isotropy, etc., and even (less satisfactorily) in Lorentz's 1904 paper.
> >
> You are just doing some unhelpful hand waving.

To the contrary, I'm informing you of highly relevant facts that contradict your beliefs.

> >> I am not 100% sure that the constancy of the speed of light assumption
> >> can be weakened to:
> >> 3. If observer 1 measures the speed of light between a source and
> >> target that are both at rest with respect to observer 1, then observer
> >> 2 in uniform motion with respect to 1, will also measure the same
> >> speed of light between the same source and target.
> >
> >That's garbled, since it doesn't define what it means to "measure a speed". A correct statement refers to specified systems of coordinates, as in Einstein's 1905 paper. That paper just asserts invariant light speed in vacuum in terms of one particular system of inertial coordinates, and then combines this with the relativity principle (and tacit assumption of no efficacious ether) to assert that it has the same invariant value in terms of every system of inertial coordinates.
>
> You measure the distance between the source and receiver of the light
> and then measure the time elapsed and then divide the two.

Again, you have not defined what it means to "measure a distance" or "measure a time". A correct statement must refer to specified systems of coordinates, as in Einstein's 1905 paper. That paper just asserts invariant light speed in vacuum in terms of one particular system of inertial coordinates, and then combines this with the relativity principle (and tacit assumption of no efficacious ether) to assert that it has the same invariant value in terms of every system of inertial coordinates.

On Friday, 1 October 2021 at 19:50:54 UTC+2, Townes Olson wrote:

> No, it was already false before I said it, and it would be false even if I never said it. Clocks obviously do not remain synchronized (in terms of any given system of inertial coordinates) if they are placed into different states of motion relative to each other. I

As anyone can check in GPS - yes, they do. I mean, of course,
the clocks made by professionals instead the ones made by
mad followers of an insane crazie.

Ricardo Jimenez wrote:

> 1. If two observers, at rest with respect to each other, synchronize
> all their clocks and rulers with each other, the two individual sets
> of clocks and rulers will remain synchronized among themselves even
> after the two observers are in uniform motion with respect to each
> other.

Yes, although it is weird to speak of a synchronization of rulers.
> 2. If two points are at rest with respect to one observer who measures
> their distance apart as d, and lie on a line perpendicular to the
> direction of motion with a second observer, the latter observer also
> observes the points being of distance apart d and perpendicular to the
> direction of motion.

This is true only to an extent, namely if “observation” does not mean actual
observation, but rather how the coordinates of the points transform.

Because the Lorentz transformation, if the direction of motion is parallel
to the x-axis, is

t' = γ (t − v/c² x)
x' = γ (x − v t)
y' = y
z' = z,

where the primed coordinates are those of a frame S' that is in relative
motion to a frame S, which uses the unprimed coordinates, at speed v.

If the motion is uniform, then for two events

e₁ ≔ (t₁, x₁, y₁, z₁) ↔ (t₁', x₁', y₁', z₁')
e₂ ≔ (t₂, x₂, y₂, z₂) ↔ (t₂', x₂', y₂', z₂')

follows (trivially)

Δy' ≔ y₂' − y₁' = y₂ − y₁ =: Δy
Δz' ≔ z₂' − z₁' = z₂ − z₁ =: Δz,

i.e. both observers will agree about the distances of those points as long
as the line connecting them is perpendicular to the direction of motion.

However, as actual observation is concerned, light-travel delay will cause
the observation of the observer “at rest” to be visibly different than that
of the observer “in motion”, especially at high speeds, a little-known
effect known as Terrell rotation:

<https://en.wikipedia.org/wiki/Terrell_rotation>
> I am not 100% sure that the constancy of the speed of light assumption

It is not an assumption, but an experimental fact.

> can be weakened to:
> 3. If observer 1 measures the speed of light between a source and
> target

Note that the one-way speed of light cannot be measured, only the two-way
speed of light can. One makes the reasonable assumption that the speed of
light is isotropic, i.e. that the one-way speed of light is equal to the
two-way speed of light.

> that are both at rest with respect to observer 1, then observer
> 2 in uniform motion with respect to 1, will also measure the same
> speed of light between the same source and target.

Yes, but that is not a "weakening" of an "assumption", but what has been and
can be observed.

The consequence of that is "time dilation" as it can be obtained from the
“light clock” thought experiment:

mirror
...
^^\
/ : \
/ : \
/ : \ c Δt
/ : \
/ : \
/ :c Δτ \
/ : \
/ v v
^------------------> light clock in relative motion at speed v
: ^ v Δt :
: :
: light clock at relative rest
:
light pulse

(c Δt)² = (c Δτ)² + (v Δt)² [Pythagorean theorem]
⇔ c² Δt² = c² Δτ² + v² Δt²
⇔ (c² − v²) Δt² = c² Δτ²
⇔ Δt² = c²/(c² − v²) Δτ²
⇔ Δt² = 1/(1 − v²/c²) Δτ²
⇔ Δt = 1/√(1 − v²/c²) Δτ = γ Δτ.
⇔ Δτ = Δt/γ.

v > 0 ⇒ γ > 1 ⇒ Δτ < Δt. ∎

See also:

<https://www.youtube.com/watch?v=qXxtqK7G4Uw&list=PLCfRa7MXBEspw_7ZSTVGCXpSswdpegQHX&index=9>

PointedEars
--
“Nature uses only the longest threads to weave her patterns
so that each small piece of her fabric reveals the organization
of the entire tapestry.”
—Richard Feynman, theoretical physicist, “Messenger Lecture” 1 (1964)

On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn wrote:

> Because the Lorentz transformation, if the direction of motion is parallel
> to the x-axis, is

In the meantime in the real world, however, the clocks
of GPS keep indicating t'=t, just like all serious clocks
always did, and your moronic lies won't change it,
trash.

Maciej Wozniak wrote:

> On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn
> wrote:
>> Because the Lorentz transformation, if the direction of motion is
>> parallel to the x-axis, is
>
> In the meantime in the real world, however, the clocks
> of GPS keep indicating t'=t, just like all serious clocks
> always did, and your moronic lies won't change it,
> trash.

“[…] The SV [space vehicle; the ed.] carrier frequency and clock rates –
as they would appear to an observer located in the SV – are offset to
compensate for relativistic effects. […]”

GPS Interface Specifications (2021). “3.3.1.1 Frequency Plan.”
<https://www.gps.gov/technical/icwg/IS-GPS-200M.pdf>

Linked from <https://www.gps.gov/technical/icwg/>.

PointedEars
--
Q: What did the female magnet say to the male magnet?
A: From the back, I found you repulsive, but from the front
I find myself very attracted to you.
(from: WolframAlpha)

Maciej Wozniak wrote:

> On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn
> wrote:
>> Because the Lorentz transformation, if the direction of motion is
>> parallel to the x-axis, is
>
> In the meantime in the real world, however, the clocks
> of GPS keep indicating t'=t, just like all serious clocks
> always did, and your moronic lies won't change it,
> trash.

“[…] The SV [space vehicle; the ed.] carrier frequency and clock rates –
as they would appear to an observer located in the SV – are offset to
compensate for relativistic effects. […]”

GPS Interface Specification (2021). “3.3.1.1 Frequency Plan.”
<https://www.gps.gov/technical/icwg/IS-GPS-200M.pdf>

Linked from <https://www.gps.gov/technical/icwg/>.

PointedEars
--
Q: What did the female magnet say to the male magnet?
A: From the back, I found you repulsive, but from the front
I find myself very attracted to you.
(from: WolframAlpha)

On 9/30/21 11:39 AM, Ricardo Jimenez wrote:
> 1. If two observers, at rest with respect to each other, synchronize
> all their clocks and rulers with each other, the two individual sets
> of clocks and rulers will remain synchronized among themselves even
> after the two observers are in uniform motion with respect to each
> other.

[I ignore the rulers as they are irrelevant.]

This is just plain wrong: Consider many clocks at rest in inertial frame
A, distributed throughout some spatial region, and mutually synchronized
in frame A. If some of the clocks are simultaneously (in A) given
identical proper accelerations until they are at rest in inertial frame
B, then:
a) the accelerated clocks are, in general, not synchronized
with each other in frame B
b) the accelerated clocks are not synchronized with any of
the clocks at rest in frame A
c) the accelerated clocks are all synchronized with each
other IN FRAME A, but that is useless as they are not at
rest in that frame.

> 2. If two points are at rest [...]

Points are not "at rest" in any sense. You need to learn the basic
concepts of relativity (and physics and geometry) before attempting to
write about it.

The aspect you seem to be trying to address is a consequence of the
Lorentz transform, not an assumption in its derivation: if a rod is at
rest in inertial frame A, and is perpendicular to the relative motion
between frame A and inertial frame B, then in both frames it is
perpendicular to the direction of relative motion, and instruments at
rest in both frames measure the same value for its length.

> I am not 100% sure that the constancy of the speed of light
> assumption [...]

Hmmm. Einstein's second postulate is NOT about "the constancy of the
speed of light", it is about the (vacuum) speed of light being
independent of the speed of its source. It can be replaced by any
experiment or statement that distinguishes the Lorentz group from the
Euclid and Galilei groups. Such as:
* pion beams exist
* the vacuum speed of light is measured to have the same value
using instruments at rest in any inertial frame
This last includes your poorly-worded statement as a specific case.

Tom Roberts

On Fri, 01 Oct 2021 21:36:47 +0200, Thomas 'PointedEars' Lahn
<PointedEars@web.de> wrote:

>> 2. If two points are at rest with respect to one observer who measures
>> their distance apart as d, and lie on a line perpendicular to the
>> direction of motion with a second observer, the latter observer also
>> observes the points being of distance apart d and perpendicular to the
>> direction of motion.
>
>This is true only to an extent, namely if “observation” does not mean actual
>observation, but rather how the coordinates of the points transform.
>
>Because the Lorentz transformation, if the direction of motion is parallel
>to the x-axis, is

I stated 2 because it is needed to justify the argument for time
dilation which is needed to justify the argument for the Lorentz
transformation. The observer at rest with respect to the light path's
endpoints comes up with a length ct' for its length and that line
forms the third side of the right triangle with hypotenuse of length
ct and second side of length vt. It has to be a right triangle
according to the unprimed observer's coodinate system.

Tom Roberts wrote:

> On 9/30/21 11:39 AM, Ricardo Jimenez wrote:
>> 1. If two observers, at rest with respect to each other, synchronize
>> all their clocks and rulers with each other, the two individual sets
>> of clocks and rulers will remain synchronized among themselves even
>> after the two observers are in uniform motion with respect to each
>> other.
>
> [I ignore the rulers as they are irrelevant.]
>
> This is just plain wrong: Consider many clocks at rest in inertial frame
> A, distributed throughout some spatial region, and mutually synchronized
> in frame A. If some of the clocks are simultaneously (in A) given
> identical proper accelerations until they are at rest in inertial frame
> B, then:
> a) the accelerated clocks are, in general, not synchronized
> with each other in frame B

Hmmm. I understood “synchronized among themselves” to mean all the clocks
observed in their respective rest frame, not from another frame.

If it is not meant that way, then you are of course correct that the
statement is wrong.

PointedEars
--
Q: How many theoretical physicists specializing in general relativity
does it take to change a light bulb?
A: Two: one to hold the bulb and one to rotate the universe.
(from: WolframAlpha)

On Sat, 02 Oct 2021 04:33:03 +0200, Thomas 'PointedEars' Lahn
<PointedEars@web.de> wrote:

>Tom Roberts wrote:
>
>> On 9/30/21 11:39 AM, Ricardo Jimenez wrote:
>>> 1. If two observers, at rest with respect to each other, synchronize
>>> all their clocks and rulers with each other, the two individual sets
>>> of clocks and rulers will remain synchronized among themselves even
>>> after the two observers are in uniform motion with respect to each
>>> other.
>>
>> [I ignore the rulers as they are irrelevant.]
>>
>> This is just plain wrong: Consider many clocks at rest in inertial frame
>> A, distributed throughout some spatial region, and mutually synchronized
>> in frame A. If some of the clocks are simultaneously (in A) given
>> identical proper accelerations until they are at rest in inertial frame
>> B, then:
>> a) the accelerated clocks are, in general, not synchronized
>> with each other in frame B
>
>Hmmm. I understood “synchronized among themselves” to mean all the clocks
>observed in their respective rest frame, not from another frame.
>
>If it is not meant that way, then you are of course correct that the
>statement is wrong.
>
>
>PointedEars

I will try to restate 1. better.

1. Suppose two observers A and B are at rest with respect to each
other and synchronize the totality of their clocks and make sure that
their rulers are of identical size. Then suppose that A and B start
moving uniformly with respect to each other. Then all of A's clocks
will still be synchronized among themselves and A's rulers will still
be of identical size. The same statement also holds with B
substituted for A.

On Friday, October 1, 2021 at 7:57:49 PM UTC-7, Ricardo Jimenez wrote:
> Suppose two observers A and B are at rest with respect to each
> other and synchronize the totality of their clocks and make sure that
> their rulers are of identical size. Then suppose that A and B start
> moving uniformly with respect to each other. Then all of A's clocks
> will still be synchronized among themselves and A's rulers will still
> be of identical size. The same statement also holds with B
> substituted for A.

That is still false. If A's separate clocks are synchronized in one state of inertial motion, and then those clocks are put into a different state of inertial motion (in the direction of their separation), they will no longer be synchronized among themselves. The same applies to B's clocks.

Also, it isn't unambiguously correct to say that their rulers will be of the same size, since you are subjecting each ruler to active acceleration to change its state of motion in terms of the original inertial coordinate system, and the ruler's spatial length contracts in terms of that original system of inertial coordinates. What you are probably trying to say is that, after the acceleration, the ruler (if it has not exceeded the limits of elastic deformation during the acceleration) will reach equilibrium in a configuration that is spatially congruent (to its original configuration in terms of the original coordinates) in terms of the inertial coordinates in which it is now at rest. Note that the intrinsic temporal phase relations between the parts of the ruler are not the same after the acceleration, so it isn't "the same" configuration, it is a congruent configuration.

In contrast, if you don't subject a ruler to any acceleration but merely describe it in terms of a different system of inertial coordinates, the intrinsic phase relations of the ruler are obviously unaffected as is everything else about the ruler, and the act that this gives the congruent description in terms of the new system is not merely a coincidence, because we choose our coordinate systems (related by Lorentz transformations) to match the dynamical results of active changes in states of motion. You can read about this in any good book on the foundations of special relativity.

On Saturday, 2 October 2021 at 00:12:19 UTC+2, Thomas 'PointedEars' Lahn wrote:
> Maciej Wozniak wrote:
>
> > On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn
> > wrote:
> >> Because the Lorentz transformation, if the direction of motion is
> >> parallel to the x-axis, is
> >
> > In the meantime in the real world, however, the clocks
> > of GPS keep indicating t'=t, just like all serious clocks
> > always did, and your moronic lies won't change it,
> > trash.
> “[…] The SV [space vehicle; the ed.] carrier frequency and clock rates –
> as they would appear to an observer located in the SV – are offset to
> compensate for relativistic effects. […]”
> GPS Interface Specification (2021). “3.3.1.1 Frequency Plan.”
> <https://www.gps.gov/technical/icwg/IS-GPS-200M.pdf>
>
> Linked from <https://www.gps.gov/technical/icwg/>.

How did you imagine it's somehow important whether
they "would appear" or not, poor halfbrain? The clocks
indicate t'=t, time is what clocks indicate and the
result of measurement is t'=t, like it always was.
Your moronic lies won't change it.

On Saturday, 2 October 2021 at 06:20:28 UTC+2, Townes Olson wrote:
> On Friday, October 1, 2021 at 7:57:49 PM UTC-7, Ricardo Jimenez wrote:
> > Suppose two observers A and B are at rest with respect to each
> > other and synchronize the totality of their clocks and make sure that
> > their rulers are of identical size. Then suppose that A and B start
> > moving uniformly with respect to each other. Then all of A's clocks
> > will still be synchronized among themselves and A's rulers will still
> > be of identical size. The same statement also holds with B
> > substituted for A.
> That is still false. If A's separate clocks are synchronized in one state of inertial motion, and then those clocks are put into a different state of inertial motion (in the direction of their separation), they will no longer be synchronized among themselves. The same applies to B's clocks.

Since we have GPS we can be absolutely sure that this moronic
bullshit is just some moronic bullshit. Of course, GPS clocks
are made by professionals, not by brainwashed fanatics of
an insane ideology.

On 10/2/2021 2:16 AM, Maciej Wozniak wrote:
> On Saturday, 2 October 2021 at 00:12:19 UTC+2, Thomas 'PointedEars' Lahn wrote:
>> Maciej Wozniak wrote:
>>
>>> On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn
>>> wrote:
>>>> Because the Lorentz transformation, if the direction of motion is
>>>> parallel to the x-axis, is
>>>
>>> In the meantime in the real world, however, the clocks
>>> of GPS keep indicating t'=t, just like all serious clocks
>>> always did, and your moronic lies won't change it,
>>> trash.
>> “[…] The SV [space vehicle; the ed.] carrier frequency and clock rates –
>> as they would appear to an observer located in the SV – are offset to
>> compensate for relativistic effects. […]”
>> GPS Interface Specification (2021). “3.3.1.1 Frequency Plan.”
>> <https://www.gps.gov/technical/icwg/IS-GPS-200M.pdf>
>>
>> Linked from <https://www.gps.gov/technical/icwg/>.
>
> How did you imagine it's somehow important whether
> they "would appear" or not, poor halfbrain?

Tom didn't imagine it, the GPS designers explicitly stated it.

> The clocks
> indicate t'=t,

Only if you believe 9192631770 = 9192631774.1.

> time is what clocks indicate

and the SV tick rate (the one based on 9192631774.1 as the divisor) is
slow so it's technically not a clock on board the SV. The one based on
9192631770 as the divisor is, of course, a good clock.

> and the
> result of measurement is t'=t, like it always was.

Only if 9192631774.1 = 9192631770. Is that what they taught you in the
communist education system?

> Your moronic lies won't change it.

Your moronic lies won't change it.

On Fri, 1 Oct 2021 21:20:26 -0700 (PDT), Townes Olson
<townesolson7@gmail.com> wrote:

>In contrast, if you don't subject a ruler to any acceleration but merely describe it in terms of a different system of inertial coordinates, the intrinsic phase relations of the ruler are obviously unaffected as is everything else about the ruler, and the act that this gives the congruent description in terms of the new system is not merely a coincidence, because we choose our coordinate systems (related by Lorentz transformations) to match the dynamical results of active changes in states of motion. You can read about this in any good book on the foundations of special

All I am trying to do, for now, is to list the various assumptions
(perhaps mistaken as you point out) about the results of gedanken
experiments that justify the time dilation/length contraction claims
that are used to justify the Lorentz transformation which is supposed
to connect what is observed about the time and space differences
between pairs of events in two 4D coordinate systems in uniform
relative motion with each other. What "good" book on relativity
assumes there is only one set of rulers and clocks shared by two
observers in uniform relative motion? The synchronization axiom
justifies, I think, the claim that the same relationship deduced
between certain special clocks (rulers) of the two coordinate systems
is shared between any other pair from each system. If it is wrong,
than that claim universally made in relativity is wrong.

On Friday, October 1, 2021 at 7:57:49 PM UTC-7, Ricardo Jimenez wrote:
> On Sat, 02 Oct 2021 04:33:03 +0200, Thomas 'PointedEars' Lahn
> <Point...@web.de> wrote:
>
> >Tom Roberts wrote:
> >
> >> On 9/30/21 11:39 AM, Ricardo Jimenez wrote:
> >>> 1. If two observers, at rest with respect to each other, synchronize
> >>> all their clocks and rulers with each other, the two individual sets
> >>> of clocks and rulers will remain synchronized among themselves even
> >>> after the two observers are in uniform motion with respect to each
> >>> other.
> >>
> >> [I ignore the rulers as they are irrelevant.]
> >>
> >> This is just plain wrong: Consider many clocks at rest in inertial frame
> >> A, distributed throughout some spatial region, and mutually synchronized
> >> in frame A. If some of the clocks are simultaneously (in A) given
> >> identical proper accelerations until they are at rest in inertial frame
> >> B, then:
> >> a) the accelerated clocks are, in general, not synchronized
> >> with each other in frame B
> >
> >Hmmm. I understood “synchronized among themselves” to mean all the clocks
> >observed in their respective rest frame, not from another frame.
> >
> >If it is not meant that way, then you are of course correct that the
> >statement is wrong.
> >
> >
> >PointedEars
> I will try to restate 1. better.
>
> 1. Suppose two observers A and B are at rest with respect to each
> other and synchronize the totality of their clocks and make sure that
> their rulers are of identical size. Then suppose that A and B start
> moving uniformly with respect to each other. Then all of A's clocks
> will still be synchronized among themselves and A's rulers will still
> be of identical size. The same statement also holds with B
> substituted for A.

Also, imagine that an infinite grid of infinitesimal clocks,
see that each of the frames containing A's centers that
for the very center of B's, as the two frames move apart
which is uniformly as they are apiece, as they leave each
other's frames, the point is that it's usually considered under
the rigid that a test charge is rigid to all the clocks in the radius
of the center, there's instead that as they move apart they
each reduce to a charge.

Basically for an ant on a surface, though it's in the surface's frame,
as it moves along each the locations is in its surface frame.

The infinite lattice of classically and non-classically infinitesimal clocks,
is a usual approximation for the field number formalism,
continuum mechanics in relativistic space-time and gravity.

Actually putting atomic clocks in a dense configuration of course
many, many times grosser than the space-time's abstract clock(s),
makes for a comprehensively high-precision experiment what as
we know from science "validates general relativity" and so on.

Which any explanation would in a way....

These atomic clock lattices are a usual wave meter in gravity.

On Saturday, October 2, 2021 at 11:52:03 AM UTC-7, Ricardo Jimenez wrote:
> All I am trying to do, for now, is to list the various assumptions
> (perhaps mistaken as you point out) about the results of gedanken
> experiments ...

It's a bit garbled to say that physics is based on "assumptions about thought experiments", unless by this you just mean that we extrapolate from our (necessarily finite) observations by induction to general principles. To be clear, physics is based on discerning patterns from actual observations and experimental results, and then by incomplete induction (since our experience is always finite and therefore incomplete) we adopt these patterns as general principles. For example, in each and every situation that we have ever observed, we have found that momentum is invariably conserved, so in the formulation of our physics we 'assume' that momentum is *always* conserved. In other words, we elevate the conservation of momentum to the status of a general physical principle. If, some fine day, we were to discover that, on Tuesday's during leap years on the winter solstice in a particular suburb of Huntsville Alabama, momentum is not conserved for red billiard balls, then we would have to admit our assumption was wrong, and we would need to update our principle accordingly. So far that has not happened.

Likewise, we have observed that, regardless of our state of motion, there invariably exists a system of space and time coordinates in which we are (at least momentarily) at rest, and in terms of which the very same homogeneous and isotropic equations of physics hold good. We assume this is always true, and elevate it to the status of a principle, which is called the principle of relativity, first discussed explicitly around 1600. We also observe other things, such as the apparent fact that elementary entities don't seem to have any "memory", e.g., a water molecule is a water molecule, and behaves like every other water molecule, regardless of whether this particular water molecule ever flowed over Niagara Falls, or has any other historical background. There are a handful of other tacit assumptions that newbies would never think to question, so we typically don't dwell on them.

Given these basic principles, most notably the principle of relativity, there is, by simple logic, only a single degree of freedom for the possible relationship between the inertia-based coordinate systems referred to in that principle. That degree of freedom can be parameterized by a single constant value. For example, if that constant were equal to 0 (as Galileo and Newton thought), it would follow that inertia-based coordinate systems are related by Galilean transformations, and massless energy would not have any inertia (so E would not equal mc^2, and so on), and there would be no time dilation or length contraction or relativity of inertial simultaneity. On the other hand, if that constant has the slightly non-zero value of 1/c^2, then E=mc^2 and we have all the relativistic effects of time dilation, length contraction, and relativity of inertial simultaneity. Any of infinitely many different measurements reveal the value of that constant, which is actually 1/c^2. Hence special relativity.

> What "good" book on relativity assumes there is only one set of rulers and
> clocks shared by two observers in uniform relative motion?

I don't think any good book assumes anything like that. Your statement seems to be gibberish.

> The synchronization axiom...

What is "the synchronization axiom"? Again, the time coordinates of a given system of inertia-based coordinates are defined by the requirement that the equations of physics take their simple homogeneous and isotropic form in terms of those coordinates. So, for example, if we shoot identical bullets from identical guns resting at the mid-point of a ruler, the bullets reach the end points simultaneously in terms of the inertial coordinates in which the ruler is at rest. This isn't an axiom, it's essentially the definition of inertia-based coordinates, i.e., coordinates in which inertia is isotropic.

> ...justifies, I think, the claim that the same relationship deduced between
> certain special clocks (rulers)...

What is special about them, and what relationships are you referring to, and what do you mean by "deduced" (as distinct from, say, observed)?

> of the two coordinate systems is shared between any other pair from each system.

Pair of what? And what does it mean for a "pair" (whatever that is) to be "from" a system? You aren't expressing any coherent thought. You need to be much more careful and explicit when trying to formulate your thoughts.

> If it is wrong, than that claim universally made in relativity is wrong.

You haven't articulated any clear claim, let alone one that is universally made in relativity. There certainly exist poor expositions of relativity, but I don't think I've ever seen one that makes the statements you are making. I suspect you began with some poor popular exposition aimed at uncritical newbies, and then added your own extrapolations and inferences to arrive at a totally garbled misunderstanding.

On Saturday, 2 October 2021 at 19:14:28 UTC+2, Michael Moroney wrote:
> On 10/2/2021 2:16 AM, Maciej Wozniak wrote:
> > On Saturday, 2 October 2021 at 00:12:19 UTC+2, Thomas 'PointedEars' Lahn wrote:
> >> Maciej Wozniak wrote:
> >>
> >>> On Friday, 1 October 2021 at 21:36:51 UTC+2, Thomas 'PointedEars' Lahn
> >>> wrote:
> >>>> Because the Lorentz transformation, if the direction of motion is
> >>>> parallel to the x-axis, is
> >>>
> >>> In the meantime in the real world, however, the clocks
> >>> of GPS keep indicating t'=t, just like all serious clocks
> >>> always did, and your moronic lies won't change it,
> >>> trash.
> >> “[…] The SV [space vehicle; the ed.] carrier frequency and clock rates –
> >> as they would appear to an observer located in the SV – are offset to
> >> compensate for relativistic effects. […]”
> >> GPS Interface Specification (2021). “3.3.1.1 Frequency Plan.”
> >> <https://www.gps.gov/technical/icwg/IS-GPS-200M.pdf>
> >>
> >> Linked from <https://www.gps.gov/technical/icwg/>.
> >
> > How did you imagine it's somehow important whether
> > they "would appear" or not, poor halfbrain?
> Tom didn't imagine it, the GPS designers explicitly stated it.

So what? What is so important whether something appear
[to a gedanken peersonn] or not? The meeasurement result
is still t'=t.

> > The clocks
> > indicate t'=t,
> Only if you believe 9192631770 = 9192631774.1.

Like always, you're mistaking t with T. Similiar, but different,
stupid Mike.

> and the SV tick rate (the one based on 9192631774.1 as the divisor) is
> slow so it's technically not a clock on board the SV. The one based on
> 9192631770 as the divisor is, of course, a good clock.

Sorry, stupid Mike. GPS staff didn't share your opinion.
Neither any sane person does. Oppositely - technically,
the clocks indicating your idiot guru's nonsenses are
not good clocks, and that's why they aren't applied
in any serious timekeeping system.

> > result of measurement is t'=t, like it always was.
> Only if 9192631774.1 = 9192631770. Is that what they taught you in the
> communist education system?

They taught me to distinguish between t and T, stupid Mike.
Actually, with many disadvantages of communism its
education system was OK.

Ricardo Jimenez wrote:

> On Fri, 1 Oct 2021 21:20:26 -0700 (PDT), Townes Olson
> <townesolson7@gmail.com> wrote:
>>In contrast, if you don't subject a ruler to any acceleration but merely
>>describe it in terms of a different system of inertial coordinates, the
>>intrinsic phase relations of the ruler are obviously unaffected as is
>>everything else about the ruler, and the act that this gives the congruent
>>description in terms of the new system is not merely a coincidence,
>>because we choose our coordinate systems (related by Lorentz
>>transformations) to match the dynamical results of active changes in
>>states of motion. You can read about this in any good book on the
>>foundations of special
>
> All I am trying to do, for now, is to list the various assumptions
> (perhaps mistaken as you point out) about the results of gedanken
> experiments that justify the time dilation/length contraction claims

The "claims" are based on observations. The thought experiments do not
justify, they illustrate.

> that are used to justify the Lorentz transformation

The Lorentz transformation came first (at least conceptually), with Lorentz’
ether theory. Einstein "only" found a simpler (better) way to derive it
(without assuming an ether), and worked out its consequences.

> which is supposed to connect what is observed about the time and space
> differences between pairs of events in two 4D coordinate systems in
> uniform relative motion with each other.

Observed as predicted.

> What "good" book on relativity assumes there is only one set of rulers and
> clocks shared by two observers in uniform relative motion?

The theories of relativity are not defined based on any (one) (text)book,
but by thousands of papers and gazillions of experiments (also counting
those in particle accelerators) in the past 115 years. The problem is
rather that you do not know about them even though you could (the
information is freely available).

> Thsynchronization axiom justifies, I think, the claim that the same
> relationship deduced between certain special clocks (rulers) of the two
> coordinate systems is shared between any other pair from each system.
> If it is wrong, than that claim universally made in relativity is wrong.

Once again, the constancy of the speed of light (in vacuum) is an
experimental fact. From that, everything else *follows*: The relativity of
simultaneity, of lengths and times (i.e. "length contraction" and "time
dilation"), the Lorentz transformation to formalize it; Doppler redshift,
the equivalence of mass and energy, spacetime and the Minkowski metric,
general relativity (with its confirmed effects, e.g.
gravitational/cosmological time dilation/redshift, deflection of light,
faster perihelion precession, black holes, and gravitational waves), the
energy–momentum relation, the mass defect, nuclear energy (nuclear fission
and fusion, including fission in planets and fusion in stars), QED, and so
on.

It is NOT just about clocks and rulers.

And so:

“If the theory of relativity is wrong, then it is damn well wrong.”

–Prof. Dr. Harald Lesch, German theoretical astrophysicist (translated)

PointedEars
--
“Science is empirical: knowing the answer means nothing;
testing your knowledge means everything.”
—Dr. Lawrence M. Krauss, theoretical physicist,
in “A Universe from Nothing” (2009)

Ricardo Jimenez wrote:

> […] What "good" book on relativity
> assumes there is only one set of rulers and clocks shared by two
> observers in uniform relative motion? The synchronization axiom
> justifies, I think, the claim that the same relationship deduced
> between certain special clocks (rulers) of the two coordinate systems
> is shared between any other pair from each system. If it is wrong,
> than that claim universally made in relativity is wrong.

Educate yourself:

<https://www.youtube.com/playlist?list=PLCfRa7MXBEspw_7ZSTVGCXpSswdpegQHX>

PointedEars
--
Q: Where are offenders sentenced for light crimes?
A: To a prism.

(from: WolframAlpha)