Those who teach special relativity consider it a very important exercise to have students decide how to measure the length of a rapidly moving object. That's religious indoctrination and a wrongheaded approach to physics. The theoretical process that physicists talk about to measure the length of a rapidly moving object requires belief in simultaneity. In actual reality, according to the math of relativity theory, simultaneity doesn't exist.

Lorentz contraction is just a peculiarity of a simplistic coordinate system that physicists believe in.

http://www.everythingimportant.org/relativity/special.pdf

The silliness is that either you don't understand the question or are purposely distorting my words. I'm not asserting that a mathematical formulation of motion or its measurement is impossible. [1]. I'm addressing the use of the convention called simultaneity and the use of a pure convention in deciding if something is objectively real. Simultaneity is used in hypothetically measuring the length of rapidly moving objects. [2]. The question is, Is Lorentz contraction objectively real?


Could you rephrase that so your meaning is clear?


I'm not disputing the need for simultaneity in measuring [the length of] a moving object. I affirmed that very clearly. I'm asserting that Lorentz contractions are not objectively real. If Lorentz contractions were objectively real, then it would also be true that nature violates ~S-symmetry. See, Do the Laws of Physics Demand that Clocks be Synchronized? ~S-symmetry means that the laws of physics do not physically compel a special synchronization of clocks. Nature does not impose a preferred clock synchronization scheme.


Right. And the question is, How could there ever be objectively real experimental evidence demonstrating that Lorentz contraction is real without equally compelling experimental evidence that nature favors E-synchronization above ~S-symmetry?


I agree that most human conventions are the simplest that humans can conceive of. However, there's a big difference between human conventionalizations and the laws of the physical universe.

I'm just a precocious inquiring mind with a degree in math imagining that simultaneity and Lorentz contraction doesn't objectively exist. My thesis is that the Lorentz contraction is just as subjective as is simultaneity. I agree that we can pretend that such things exist and that such a pretense is internally self-consistent. Why is that relevant? I am asserting that the imagined everyday shrinking of rulers is not a real objective phenomenon.


When I was a child, I spoke as a child, I understood as a child, I thought as a child; but when I became a man, I put away childish things. -- The Apostle Paul to the Corinthians.


I've written a simple, flawless, easy to understand interpretation of the Lorentz transformation [1] but can't get a single endorsement for it to be included in the physics.ed-ph section of arXiv. I've made the announcement at sci.physics.research and, to this date, no one there can get beyond their irrational, emotional, knee-jerk reactions. [3]. Apparently, tradition and prejudice have greater weight than reason and logic.


I believe that physicists are promoting naive human conventionalizations as physical, natural law. Lorentz contraction, as represented by the high priests of physics and the popularizers of science, is a misleading and unscientific theory that falsely suggests that a subjective convention is a very objective and real fact about the nature of the physical universe. See my reply to Tom Roberts.


Relativity Lite is merely the most obvious interpretation of the Lorentz transformation without the imposed clutter of having to believe in the conventionality of simultaneity as objective reality.

One is, of course, permitted to add whatever clutter to the distilled essence of relativity that they desire. I just don't understand why including the non-essentials is required for publishing at http://xxx.lanl.gov.

In relativity, there are plenty of statements and gedanken measurements that are coordinate independent. Such things are objectively real.

Lorentz contraction is coordinate dependent. It is subjective, misleading and not objectively real.

Away with such nonsense!

Yes.


Apparently, you don't perceive any physical distinction between rotating in space and traveling at relativistic speeds.


I believe in rulers. You believe in shrinking rulers and label my belief in rulers silly.


I wrote: "The Lorentz transformation group may be interpreted physically as a universal, everywhere present multi-clock that defines time at every point."

Is it that you don't understand the phrase, "may be interpreted" or are you insulted that I have discovered a revolutionary new way to think about relativity and that the limited vocabulary of traditional physics isn't rich enough to explain it?


Hypocrite, Physicists are infatuated with shrinking rulers and they use the illustration incessantly, but when I ask my readers to imagine sliding rulers you disapprove as if such an idea is unimaginable.

We don't live in objective reality. Any measurement we make isn't a measurement of reality - reality is an infinite dimenionsal Hilbert space, we live in a projection of that space.

There is no cosmic everywhere present ``now.'' Only absolutes exist. Why then must everyone believe in shrinking rulers?

yes, it is objectively real. You measure the length of something by putting a ruler at one end of the something and read off the number on the ruler where the other end aligns with it. (This is how you do it regardless of how fast it may be moving relative to you.) If you do this for a moving object (along the direction of its motion), you will find this number to be less than you would find if it later slows down and comes to rest. The Lorentz transformation eqns. (which you fervently believe in since you are obsessed with alternative ways of deriving them) show this rather convincingly. Thus a moving object is contracted => Lorentx contraction is objectively real.

Chris,

I seriously doubt that you understand the issues or recognize the presuppositions that you are using. If a 1+1 dimensional spacetime were governed by the group of transformations generated by equations (78) and (79) of my paper, what would be the outcome of your proposed experiment? How would moving objects shrink in a nonzero epsilon universe? Can you derive the amount of shrinkage mathematically in this instance?

Oh. Now he doesn't know how to derive length contraction...

x'_1 = ((1 + eps*v)*x_1 - vt)*gamma
x'_2 = ((1 + eps*v)*x_2 - vt)*gamma

=> x'_1 - x'_2 = gamma*(1 + eps*v)*(x_1 - x_2)

=> (x_1 - x_2) = 1/gamma*(x'_1 - x'_2)/(1 + eps*v)

= sqrt(1 - v^2/c^2)*(x'_1 - x'_2)/(1 + eps*v)

There you go, length contraction!

Of course, even though you keep including it, eps = 0, so this reduces to

(x_1 - x_2) = sqrt(1 - v^2/c^2)*(x'_1 - x'_2)

Chris,

The way you compute the length of a moving object isn't physically relevant. Why should a clock resynchronization scheme alter physical reality?

You seem to have difficulty understanding the 1+1 dimensional nonzero epsilon universe. Try to find an informed physics professor and ask him to explain it to you. A 1+1 dimensional nonzero epsilon universe is isomorphic to 1+1 dimensional Minkowski space. These two spacetimes are mathematically and physically indistinguishable.

I'm not surprised that isomorphic universes with different clock synchronization schemes yield dissimilar coordinate dependent results. Thanks for demonstrating this simple fact. You have confirmed my thesis with a simple computation.

Believing in Lorentz contraction requires accepting a universal everywhere present "now". True laws of physics are independent of how clocks are synchronized.

Of course it is. You have to do it right to get the correct physical length.


It shouldn't, and it doesn't. We've been over this before.


I understand it very well. It's a 2D universe with transformation equations that you made up. Such is not our universe.


I guarantee most physics professors have never heard of such gobbledygook.


Prove your claim. As far as I can tell a non-zero epsilon universe gives different values for length contraction and time dilation. (see above). Thus it is NOT physically indistinguishable from Minkowski space since those are measurable quantities. Our universe has epsilon=0, as has been experimentally verified to incredible accuracy.

Perhaps you can find a source that talks about or has this epsilon that you have mysteriously introduced. In order for it to be isomorphic to our universe the meanings of space and time would have to change. Anyway, I'll leave up to you to figure this out and save your own ass from humiliation on this matter.


Length contraction is a coordinate independent result.


Oh shut up.


No it doesn't. It requires that the concept of "now" is well-defined in any inertial frame.


Even a broken clock is right twice a day. Too bad it's always the same time it gets right.