The Symmetric Twin Paradox [Physics]

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From: Peter Webb on 18 Jun 2010 01:58

"Koobee Wublee" <koobee.wublee(a)gmail.com> wrote in message
news:2803143b-dad0-446a-a8a5-e5e8d4dbc1c5(a)z10g2000yqb.googlegroups.com...
> On Jun 17, 6:21 am, Tom Roberts wrote:
>> colp wrote:
>
>> > The symmetric twin thought experiment (as described in the OP) is such
>> > an experiment.
>>
>> No. It is a GEDANKEN, not an experiment. There are no actual measurements
>> of
>> this situation.
>
> Of course not. I know you would agree that a paradox is not a
> physical reality. So, please clarify with professor Drape aka PD who
> thinks a paradox is still a possibility in real life.
>
>> > In the experiment SR predicts that the twins will both be younger than
>> > each other when they return to Earth, which is of course impossible.
>>
>> This is just plain not true. You and that paper did not actually use SR.
>> The
>> comic book used does not describe the actual theory accurately enough to
>> be useful.
>
> Oh, careful here. You are treading on thin ice while embracing the
> principle of relativity. The time dilation in the Lorentz transform
> must be mutual. <shrug>
>
> As a on-stage magician, I have called your mathemagical tricks. There
> is a slight difference between Larmor's transform and the later
> Lorentz transform, but this slight difference is going to determine
> what is reality and what is fairy tale. Larmor's and the Lorentz
> transforms are different only that Larmor's requires one of the two
> observers to be the stationary background of the Aether while the
> Lorentz does not. The Lorentz transform can only possibly valid if
> and only if these two observers are moving in parallel to each other
> against the stationary background of the Aether.

Excellent. Then it must be possible to design an experiment which determines
if SR is correct. According to you, SR will only make the correct prediction
occur if the two objects are moving in parallel against the stationary
background of the ether.

How about an experiment with two clocks that take different paths - say one
is put on an airplane and flies in a loop, and the other stays at home. Or,
even better, you measure the decay rates of hot atomic nucleuses, which
being hot are in rapid motion and should decay slower according to SR. These
are obviously not in parallel paths to cold nucleuses.

So, all we have to do to determine if you are correct is find an experiment
where clocks are taken in non-parallel paths, and see if SR still predicts
the relative ages correctly. Or measure the decay rates of extremely hot
radioactive materials. Or even just compare the lifetime of stationary K
mesons vs those generated in cyclotrons and which are clearly not on
parallel paths.

I wonder if somebody has ever done these types of experiments?

From: Koobee Wublee on 18 Jun 2010 02:06

On Jun 17, 9:18 pm, stevendaryl3...(a)yahoo.com wrote:

> There is no paradox here! To say that SR leads to a paradox,
> you need to show that there is some experiment that can be
> performed such that SR gives two different ways to calculate
> the results, which gives two different answers.

You are indeed out of this world like my six-year-olds who would
always come up with a good story explaining what they should have ice
cream before any meals.

Since a paradox can never be proven valid in which I would bet my life
savings on, it is absolutely not possible to come up with an
experiment to support any paradox. We have someone who does not
understand the basic logic going absolutely wild and insane here.
<shrug>

> What SR predicts is this: For any trip, the elapsed time on a
> clock will be given by: [snipped the rest of nonsense]

That is a typical Einstein Dingleberry who cannot listen to any logic
but gulping down mystic nonsense at any chance. How many times have
you been wrong?

<shrug>

From: kado on 18 Jun 2010 06:15

On Jun 17, 6:21 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote:
>
snip
>
> No. It is a GEDANKEN, not an experiment. There are no actual measurements of
> this situation.
>
> > In the experiment SR predicts that the twins will both be younger than
> > each other when they return to Earth, which is of course impossible.
>
> This is just plain not true. You and that paper did not actually use SR. The
> comic book used does not describe the actual theory accurately enough to be useful.
>
snip
>
> Those are not the real solution. The REAL solution is to actually use SR in the
> analysis of this gedanken.
>

You are correct in stating twin paradox is a gedanken, and not
an empirical experiment.
Everone understands (or should understand) that a thought
experiment is very susceptible to errors.
However, just because an empirical experiment is conducted,
this does not mean the researchers arrive at the correct
conclusions.

Nevertheless, what you do not seem to realize and be able to
accept is that the whole of Einstein's SR and GR are based
on gedankens, and not a bit of these are based on empirical
experimentation!

The gedankin based idea of relativistic mass was demonstrated
as false by the empirical Eotvos experiment of Dr. Robert Dicke.
This experiment empirically demonstrated that the mass of any
body remains constant to better than 99,999,999,999 parts in
100 billion regardless of speed.

So post Einsteinian Relativity now employs the notion of
invariant mass.

You and most relativists also cannot seem realize that post
Einsteinian Special Relativity and General Relativity are not
Einstein's SR or GR (e.g., relativistic mass is now invariant
mass, time contracrion is now dilated time, etc.,). So many
relativists cannot seem to accept that both are whole new
theories of relativity, wherein any and all the reasoning and
mathematics pertaining to mass and contracted time within
Einstein's SR and GR just do not apply in these 2 new
theories.

So what SR do you propose to analyze this gedanken?

Furthermore, the twin paradox cannot be empirically
modeled or duplicated.
Trying to empirically model/reproduce this paradox would
be just like trying to empirically change a pumpkin into the
coach and physically morphing mice into the coachmen of
the fairytale of Cinderella.

It is not possible to empirically model or replicate fairy tales.

Nevertheless, probably the primary reason there is so much
BS on both sides of this current argument is that this is a
subject concerning time.

Science still does not truly understand time!

Therefore I propose another paradox initiated by the tenets
of Einsteins SR that is independent of time, i.e.,: The
paradox of rapidly spinning (rotating), absolutely rigid,
perfectly round discs moving near the speed of light.

(I conceived this paradox when writing the treatise titled:
The Search for Reality and the Truths. Now I make no
claim that I was the very first to formulate this paradox, but
I found no mention of it in any of my studies of Relativity.
So to keep all the mediocre minds on this newsgroup from
making a big deal about who was first, lets just say
that I independently developed this paradox.)

The concept of tensors (i.e., the contraction of the length
a body in the direction of motion, but not the height or
width) is a fundamental tenet of both Einsteins, and post
Einsteinian SR and GR. Furthermore, this idea was
originated by Lorentz, and is an integral part of the
Lorentz Transformation. So this paradox is applicable to
not only SR and GR, but also the ether theory of Lorentz.

So all are open to the paradox of very rapidly rotating,
perfectly round, RIGID discs (e.g., a Frisbee) moving
near the speed of light wherein length, but not height
and width contracts as tensors (so the physical form
must continually change depending on the speed and
rotation).

Furthermore, all these continual changes of form (that
depends of both the rate of spin and change of position)
must occur without generating any heat and/or sound.
(Sound is the physical aural result of vibration and is a
form of energy). So if the deformations responsible for
sound requires energy, how does this affect the tensor
mechanics without also violating the Laws of
Thermodynamics. Moreover, the need for this
deformation energy would then prevent Einsteins uniform
motion that SR is all about.

In other words; the deformations would also tire inertia,
and the motion would not be uniform, but nonuniform,
i.e., deceleration, so only explainable by GR, because SR
would be invalid if uniform motion is a fallacy. But how
can GR be valid if both SR and the Lorentz Transformation
are both invalid?

So are not the whole ideas that Nature is time symmetrical
and the tensors of Einstein in the same category as the
notion of the relativity of mass?

D.Y. Kadoshima

From: Tom Roberts on 18 Jun 2010 11:45

kado(a)nventure.com wrote:
> On Jun 17, 6:21 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote:
>> No. It is a GEDANKEN, not an experiment. There are no actual measurements of
>> this situation.
>
> You are correct in stating twin paradox is a gedanken, and not
> an empirical experiment.
> Everone understands (or should understand) that a thought
> experiment is very susceptible to errors.
> However, just because an empirical experiment is conducted,
> this does not mean the researchers arrive at the correct
> conclusions.

A correct analysis using the theory arrives at a correct conclusion AS PREDICTED
BY THE THEORY. Whether or not this is what actually occurs in the world we
inhabit is the subject of experiment, and cannot possibly be determined with
gedankens.

In this case, the usual "twin paradox" has been implemented experimentally, and
the result is as predicted by SR. The "symmetric twin paradox" has not been
implemented experimentally AFAIK, but can be considered as a straightforward
extension of the usual one.

> Nevertheless, what you do not seem to realize and be able to
> accept is that the whole of Einstein's SR and GR are based
> on gedankens, and not a bit of these are based on empirical
> experimentation!

This is WILDLY untrue. There are HUNDREDS of experiments that confirm various
predictions of SR, and directly refute Newtonian mechanics.

http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html

In particular, there are several experiments that DIRECTLY implement the "twin
paradox", and which confirm the prediction of SR.

The experiment by Bailey et al is a particularly appropriate one.

> You and most relativists also cannot seem realize that post
> Einsteinian Special Relativity and General Relativity are not
> Einstein's SR or GR (e.g., relativistic mass is now invariant
> mass, time contracrion is now dilated time, etc.,). So many
> relativists cannot seem to accept that both are whole new
> theories of relativity, wherein any and all the reasoning and
> mathematics pertaining to mass and contracted time within
> Einstein's SR and GR just do not apply in these 2 new
> theories.

This is just plain not true. It is true that the meaning of "mass" has evolved
since 1905, and now means an invariant quantity intrinsic to objects [#]. But
the basic theory known as SR is the same as Einstein presented in 1905 -- only
the vocabulary and mode of presentation is different.

[#] This is the most straightforward updating of the meaning of
"mass" from Newtonian mechanics to SR; "relativistic mass" was not.
That's basically why "relativistic mass" is now an anachronism.

> Furthermore, the twin paradox cannot be empirically
> modeled or duplicated.

Not true. See the above link, specifically the section titled "Tests of the Twin
Paradox".

> Therefore I propose another paradox initiated by the tenets
> of Einstein�s SR that is independent of time, i.e.,: The
> paradox of rapidly spinning (rotating), absolutely rigid,
> perfectly round discs moving near the speed of light.
> [... excessively naive discussion]

Look up the "Ehrenfest paradox".

Before attempting to criticize SR, you need to learn what the theory ACTUALLY IS.

Tom Roberts

From: PD on 18 Jun 2010 14:52

On Jun 18, 5:15 am, "k...(a)nventure.com" <k...(a)nventure.com> wrote:

>
> You are correct in stating twin paradox is a gedanken, and not
> an empirical experiment.
> Everone understands (or should understand) that a thought
> experiment is very susceptible to errors.
> However, just because an empirical experiment is conducted,
> this does not mean the researchers arrive at the correct
> conclusions.

The only conclusion arrived from an experiment is whether its results
agree with the predictions of a theory or not. Very often, competing
theories make different predictions about what will be observed, and
in such cases, the conclusion from the experiment is which theory
agrees with the measurement and which theory does not.

As for your claim that experiments are not to be trusted, this is the
reason that experimental results are taken with a grain of salt until
confirmed by an independent investigator, usually with complementary
methods, which tends to isolate sources of error not already accounted
for. If however you are taking the stand that experimental results are
untrustworthy notwithstanding this verification, then my only response
is that you don't like the scientific method.

>
> Nevertheless, what you do not seem to realize and be able to
> accept is that the whole of Einstein's SR and GR are based
> on gedankens, and not a bit of these are based on empirical
> experimentation!

This is a freshman mistake. Einstein used gedankens to explain his
reasoning with SR and GR. They are a pedagogical device only. However,
relativity wasn't taken very seriously until its real experimental
predictions started getting confirmed in real measurements.

>
> You and most relativists also cannot seem realize that post
> Einsteinian Special Relativity and General Relativity are not
> Einstein's SR or GR (e.g., relativistic mass is now invariant
> mass, time contracrion is now dilated time, etc.,). So many
> relativists cannot seem to accept that both are whole new
> theories of relativity, wherein any and all the reasoning and
> mathematics pertaining to mass and contracted time within
> Einstein's SR and GR just do not apply in these 2 new
> theories.

Physicists do not INVENT laws of physics. They *discover* them. They
are not creations like poems or paintings. They exist outside of us,
and our description of them changes a little bit as we get to know
them more. Relativity is an aspect of nature, first described by
Galileo, then the description was expanded quite a bit by Einstein
with SR, and then expanded quite a bit more by Einstein with GR.

Likewise, the original discoverers of dinosaurs mis-strung the found
fossilized leg bones, giving the dinosaurs a stance like a lizard and
therefore led to their characterization as prehistoric reptiles. It
wasn't until much later that it was found that the correct orientation
of the bones made them more closely related to birds, so that a T-Rex
is a closer cousin to a chicken than to crocodile. Nevertheless,
dinosaurs are dinosaurs and nothing about them has changed even though
our understanding of them has slowly modified over time.

>
> Furthermore, the twin paradox cannot be empirically
> modeled or duplicated.

This is simply incorrect. The GPS system includes the results of the
twin paradox in its operation.

>
> So all are open to the paradox of very rapidly rotating,
> perfectly round, RIGID discs (e.g., a Frisbee) moving
> near the speed of light wherein length, but not height
> and width contracts as tensors (so the physical form
> must continually change depending on the speed and
> rotation).

Lorentz contraction is not a mechanical deformation. If you thought it
was, then you need to learn again what relativity in fact says.

>
> Furthermore, all these continual changes of form (that
> depends of both the rate of spin and change of position)
> must occur without generating any heat and/or sound.
> (Sound is the physical aural result of vibration and is a
> form of energy). So if the deformations responsible for
> sound requires energy, how does this affect the tensor
> mechanics without also violating the Laws of
> Thermodynamics. Moreover, the need for this
> deformation energy would then prevent Einsteins uniform
> motion that SR is all about.
>
> In other words; the deformations would also tire inertia,
> and the motion would not be uniform, but nonuniform,
> i.e., deceleration, so only explainable by GR, because SR
> would be invalid if uniform motion is a fallacy. But how
> can GR be valid if both SR and the Lorentz Transformation
> are both invalid?
>
> So are not the whole ideas that Nature is time symmetrical
> and the tensors of Einstein in the same category as the
> notion of the relativity of mass?
>
> D.Y. Kadoshima