What is the Generalized Approach to Lorentzian Relativity?

[PhizzicsPhan]

Hendrik Lorentz, a Nobel Prize-winning physicist who was a mentor to Einstein, developed his own theory of relativity before Einstein. Einstein's theory uses the "Lorentz transformations" explicitly, but the interpretation of these formalisms is quite different in each theory.

Einstein made the speed of light absolute in his theory, as a postulate, which results necessarily in the malleability of space and time (because the speed of light is measured necessarily by distance/time, so, if the speed of light is kept constant, distance and/or time must be malleable). Ironically, then, in Einstein's theory only the speed of light is absolute and all other relevant variables are relative.

Lorentz, however, viewed the null result of Michelson-Morley, and thus the Lorentz transformations themselves, as resulting from the interaction of matter with an immaterial ether. That is, as matter speeds up it becomes compressed in the direction of motion, similar to how matter will expand as it is heated and contract when cooled. For Lorentz, space and time were absolute and the speed of light was relative, depending on the motion of the observer, as is the case with all other motion in our universe.

Lorentzian and Einsteinian relativity are today viewed as being empirically equivalent because they share the same key formalisms, though of course Lorentz is remembered as a footnote to Einstein's renown.

However, I'm curious what people can suggest about a generalized approach to Lorentzian relativity? Did Lorentz himself generalize his theory of relativity to apply to all frames and not just inertial frames, as Einstein did, or have others successfully generalized Lorentzian relativity?

With increasing interest in the "vacuum" or "Higgs field" as the modern-day equivalents of the ether, it seems that more physicists are taking background dependent theories seriously. This would of course make unification with quantum mechanics that much easier because QM is background dependent (even though QFT is not).

 

[Bill_K]

Ironically, then, in Einstein's theory only the speed of light is absolute and all other relevant variables are relative.

How is this "ironic"?

Lorentz, however, viewed the null result of Michelson-Morley, and thus the Lorentz transformations themselves, as resulting from the interaction of matter with an immaterial ether. That is, as matter speeds up it becomes compressed in the direction of motion, similar to how matter will expand as it is heated and contract when cooled.

Note this was entirely empirical. No explanation was offered as to why matter behaved in this strange way.

For Lorentz, space and time were absolute and the speed of light was relative, depending on the motion of the observer, as is the case with all other motion in our universe.

This is entirely at odds with observation.

Lorentzian and Einsteinian relativity are today viewed as being empirically equivalent because they share the same key formalisms, though of course Lorentz is remembered as a footnote to Einstein's renown.

No one views them as equivalent, because in fact they are not.

With increasing interest in the "vacuum" or "Higgs field" as the modern-day equivalents of the ether, it seems that more physicists are taking background dependent theories seriously. This would of course make unification with quantum mechanics that much easier because QM is background dependent (even though QFT is not).

Special relativity was unified with quantum mechanics back in the 1940s and 1950s. The discovery of the Higgs field would in no way suggest that Einsteinian relativity needed to be replaced with something that was frame dependent.

 

[harrylin]

Hendrik Lorentz, a Nobel Prize-winning physicist who was a mentor to Einstein, developed his own theory of relativity before Einstein. Einstein's theory uses the "Lorentz transformations" explicitly, but the interpretation of these formalisms is quite different in each theory.

Einstein made the speed of light absolute in his theory, as a postulate, which results necessarily in the malleability of space and time (because the speed of light is measured necessarily by distance/time, so, if the speed of light is kept constant, distance and/or time must be malleable). Ironically, then, in Einstein's theory only the speed of light is absolute and all other relevant variables are relative.

Lorentz, however, viewed the null result of Michelson-Morley, and thus the Lorentz transformations themselves, as resulting from the interaction of matter with an immaterial ether. That is, as matter speeds up it becomes compressed in the direction of motion, similar to how matter will expand as it is heated and contract when cooled. For Lorentz, space and time were absolute and the speed of light was relative, depending on the motion of the observer, as is the case with all other motion in our universe.

Lorentzian and Einsteinian relativity are today viewed as being empirically equivalent because they share the same key formalisms, though of course Lorentz is remembered as a footnote to Einstein's renown.

However, I'm curious what people can suggest about a generalized approach to Lorentzian relativity? Did Lorentz himself generalize his theory of relativity to apply to all frames and not just inertial frames, as Einstein did, or have others successfully generalized Lorentzian relativity?

With increasing interest in the "vacuum" or "Higgs field" as the modern-day equivalents of the ether, it seems that more physicists are taking background dependent theories seriously. This would of course make unification with quantum mechanics that much easier because QM is background dependent (even though QFT is not).

Einstein downplayed the differences in his 1907 summary of their papers; not surprisingly SR became then known as the theory of Einstein and Lorentz. See also the first collection of papers on SR [1].

Concerning a generalization to accelerated reference systems, I'm not aware of such an attempt by Lorentz; instead he wrote a book on "The Einstein Theory of Relativity" in order to explain it.

However it should be noted that nowadays GR is regarded as a theory of gravitation, there is little interest for accelerated systems which are already well described with SR. One attempt that I know of with a Lorentzian approach to gravitation is a publication by Schmelzer[2]. But even Einstein suggested in 1920 (as well as in 1924) that SR corresponds to the ether of Lorentz, and that GR's space without an ether is "unthinkable"[3].

Note that definitely length contraction is not a compression in anyone's interpretation. For more on that, see discussions of Bell's spaceship "paradox".

[1]The Principle of Relativity (Lorentz et al)
http://www.betterworldbooks.com/index.aspx/the-principle-of-relativity-id-0486600815.aspx

[2] http://www.ilja-schmelzer.de/papers/glet.pdf
(apparently accepted for publication in Advances in Applied Clifford Algebras)

[3] http://www.tu-harburg.de/rzt/rzt/it/Ether.html (Einstein)Harald

PS. Nowadays the background concept is receiving renewed attention due to realistic interpretations of QM, such as by Bohm - is that what you meant?

 

[TrickyDicky]

But even Einstein suggested in 1920 (as well as in 1924) that SR corresponds to the ether of Lorentz, and that GR's space without an ether is "unthinkable"[3].

And this suggestion of Einstein seems to be ratified by a kind of modern MM experiment, this time well founded, that shows the GR ether Einsteins talks about (not the old "ether fluid"): the detection of the CMB dipole.

 

[harrylin]

And this suggestion of Einstein seems to be ratified by a kind of modern MM experiment, this time well founded, that shows the GR ether Einsteins talks about (not the old "ether fluid"): the detection of the CMB dipole.

Such statements have been made in the literature ... but were there not also objections against that interpretation? Anyway, the phrase "CMB dipole" isn't exactly a theory of gravity.

 

[TrickyDicky]

Such statements have been made in the literature ... but were there not also objections against that interpretation?

Sure.

Anyway, the phrase "CMB dipole" isn't exactly a theory of gravity.

You are right, and admittedly my phrase is a little cryptic due to it, I'll try to be more explicit some other occasion ;)

 

[cosmik debris]

Lorentzian and Einsteinian relativity are today viewed as being empirically equivalent because they share the same key formalisms, though of course Lorentz is remembered as a footnote to Einstein's renown.

Yes, there are a whole class of LET (Lorentz Ether Theories) that are experimentally indistinguishable from SR. Einstein's just seems simpler and there is no bothersome Ether frame that can't be detected.

However, I'm curious what people can suggest about a generalized approach to Lorentzian relativity? Did Lorentz himself generalize his theory of relativity to apply to all frames and not just inertial frames, as Einstein did, or have others successfully generalized Lorentzian relativity?

I'm sure he was working on it but I haven't seen any writings of his to confirm this, It is well known that Hilbert was and was taking a different approach. He was heavily influenced by Einstein though.

With increasing interest in the "vacuum" or "Higgs field" as the modern-day equivalents of the ether, it seems that more physicists are taking background dependent theories seriously. This would of course make unification with quantum mechanics that much easier because QM is background dependent (even though QFT is not).

Hmmm, background dependent means that there is an a priori geometry. QFT is background dependent. It can be solved in curved manifolds but it doesn't generate them. Background independence is just seen as being geometrically nicer. I believe some String theories start off with some dependence but reproduce GR at the classical limit.