A quick question on the twin paradox (quick I promise)

In summary, the conversation discusses the topic of non-inertial frames in special relativity, particularly in relation to the "clock paradox" and the misconception that non-inertial frames cannot be analyzed using special relativity. The conversation also mentions various textbooks that address this topic, including Modern Physics by Tipler and Llewellyn and Spacetime Physics by Taylor and Wheeler.
  • #1
nrqed
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I am reading ''Modern Physics`by Tipler and Llewellyn, 4th edition, page 52.

They say something which, unless I am completely confused, is completely wrong.

I cite (Ulysses is the twin in the spaceship, they use [itex] \Delta t_{Earth}= \gamma \Delta_{spaceship}[/itex] and then say:

''...we cannot do the same analysis in the frame of the spaceship because it does not remain in an inertial frame during the round trip; hence it falls outside of the special theory and no paradox arises,. The laws of physics can be formulated so as to be invariant for accelerated observers, which is the role of general relativity''

(emphasis mine).

As far as I understand, this entire paragraph is completely wrong. There is no problem treating accelerated observers in SR. I am surprised to see this in a fairly recent textbook (2003).

Am I totally in the left field?
 
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  • #2
You're right - special relativity can be used to compare the wristwatches of accelerated twins in Minkowski spacetime.

The book Spacetime Physics by Taylor amd Wheeler, first published in the 60's, does this in a worked exercise.

This is a myth that refuses to die.

Regards,
George
 
  • #3
George Jones said:
You're right - special relativity can be used to compare the wristwatches of accelerated twins in Minkowski spacetime.

The book Spacetime Physics by Taylor amd Wheeler, first published in the 60's, does this in a worked exercise.

This is a myth that refuses to die.

Regards,
George

Thanks,

Indeed...But it is no tsuprising that it is still such a strong myth when a *textbook* perpetuates this explicitly. I was flabbergasted to see this in a textbook!
 
  • #4
Part of the problem is that, for many, "SR" is only about "inertial frames" and non-inertial frames are only treated in "GR".

Of course, the modern view distinction is that "SR" deals with zero-curvature-R4 spacetimes, "GR" handles generally-curved spacetimes on general manifolds (of which SR is a special case).

In this light, the above is like saying that "Euclidean geometry" is only about Cartesian coordinates and
polar coordinates are only treated in "Riemannian geometry".

Here's one of my favorite papers on the clock paradox:
http://links.jstor.org/sici?sici=0002-9890(195901)66%3A1%3C1%3ATCPIRT%3E2.0.CO%3B2-L
"The Clock Paradox in Relativity Theory"
Alfred Schild
The American Mathematical Monthly, Vol. 66, No. 1. (Jan., 1959), pp.1-18.
 
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  • #5
nrqed said:
But it is not suprising that it is still such a strong myth when a *textbook* perpetuates this explicitly. I was flabbergasted to see this in a textbook!

And I think that there are other books that say the same thing, unfortunately.

I think that part of the problem is that often relativity (both SR and GR) does not really receive enough attention in the undergraduate and graduate curricula, so that people that write general texts sometimes didn't see much relativity when they were students.

I understand the reasoning - there are so many subjects to cover that some topics necessarily receive superficial treatment - but this is a shame, because there are now so many nice relativity books from which to choose.

Regards,
George
 
  • #6
Apart from Wheeler and Taylor, are there any other SR books that discuss the topic of non-inertial frames in SR?
 
  • #7
neutrino said:
Apart from Wheeler and Taylor, are there any other SR books that discuss the topic of non-inertial frames in SR?

A Traveler's Guide to Spacetime by Moore, a very nice introduction to special relativity, mentions acceleration, but doesn't go into a lot of detail. The Geometry of Minkowski Spacetime by Naber treats acceleration, but this book is maybe meant more for math students than physics students.

As pervect has mentioned a number of times, a nice advanced treatment of acceleration in SR is chapter 6 of Gravitation by Misner, Thorne, and Wheeler.

Regards,
George
 
  • #8
George Jones said:
A Traveler's Guide to Spacetime by Moore, a very nice introduction to special relativity, mentions acceleration, but doesn't go into a lot of detail. The Geometry of Minkowski Spacetime by Naber treats acceleration, but this book is maybe meant more for math students than physics students.

As pervect has mentioned a number of times, a nice advanced treatment of acceleration in SR is chapter 6 of Gravitation by Misner, Thorne, and Wheeler.

Regards,
George
Thanks. I would prefer a proper textbook treatment, and hopefully, one fine day I'll get that BIG, black textbook. :biggrin: Thanks also to nrqed for this thread. Prior to this I wasn't aware of the treatment of NI frames in SR.
 

FAQ: A quick question on the twin paradox (quick I promise)

1. What is the twin paradox?

The twin paradox is a thought experiment in physics that involves two identical twins, one of whom travels at high speeds in space while the other remains on Earth. When the traveling twin returns, they will have aged less than the twin who stayed on Earth, leading to the paradox of the twins having different ages despite being born at the same time.

2. How does the twin paradox relate to the theory of relativity?

The twin paradox is a consequence of the theory of relativity, specifically the concepts of time dilation and the relativity of simultaneity. These principles state that time passes differently for objects in motion relative to each other and that there is no universal concept of "simultaneous" events.

3. Can the twin paradox be observed in real life?

While the twin paradox is a thought experiment, it has been observed in real life through experiments with atomic clocks. For example, astronauts on the International Space Station experience time dilation due to their high speeds, causing them to age slightly slower than people on Earth.

4. Is there a resolution to the twin paradox?

Yes, the twin paradox can be resolved by taking into account the entire journey of the traveling twin, including the acceleration and deceleration required to change direction. When these factors are considered, it can be seen that both twins have experienced the same amount of time passing.

5. Can the twin paradox be applied to other scenarios?

While the twin paradox is typically used to explain the effects of relativity on space travel, it can also be applied to other scenarios involving high speeds and acceleration, such as the movement of particles in particle accelerators. However, the paradox may not be as easily understood in these contexts as in the original thought experiment.

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