- #1
zenith8
- 361
- 2
Hi,
I'm trying to understand Lorentzian relativity (Lorentz ether theory, whatever) which is empirically equivalent to the Einsteinian STR. I have, however, a problem in comprehending length contraction.
In the Lorentz theory we have a preferred frame and length contraction is a real physical effect. It has a causal explanation in terms of motion of the body with respect to this absolute space which causes distortions in the electromagnetic field and hence in the intermolecular forces holding rods and clocks together.
Of course no experiment has ever been performed which checks length contraction directly, as there is no known way to accelerate a macroscopic object to relativistic speeds.
However, why doesn't the following imply a difference between Einsteinian STR and Lorentz?
Imagine we can build a spaceship which will travel at 0.995c. In the frame of a stationary observer, everyone agrees that the spaceship looks squished as it flies past (because of a perspective effect in Minkowski spacetime for STR, or because it actually is squished for Lorentz).
However, if I am actually on the ship then other things inside either should look squished (because they are - Lorentz) or they do not look squished (because all inertial frames are equivalent - Einstein). Now whenever I have seen this discussed one just reads that in Lorentz theory measuring rods are distorted too so I can't measure the effect. But surely if I'm going at 0.995c then things will just look distorted (spheres not being spherical etc) and I can tell the damned measuring rod is a lot shorter than it used to be (because it's now square, rather than a long rectangular metre rule).
So maybe it's because my eyes are distorted, or whatever - but isn't this dangerous? Being compressed to the thickness of a piece of cardboard can't be good for the human body surely..
What's the flaw here? All opinions gratefully received.
Cheers,
Zenith
I'm trying to understand Lorentzian relativity (Lorentz ether theory, whatever) which is empirically equivalent to the Einsteinian STR. I have, however, a problem in comprehending length contraction.
In the Lorentz theory we have a preferred frame and length contraction is a real physical effect. It has a causal explanation in terms of motion of the body with respect to this absolute space which causes distortions in the electromagnetic field and hence in the intermolecular forces holding rods and clocks together.
Of course no experiment has ever been performed which checks length contraction directly, as there is no known way to accelerate a macroscopic object to relativistic speeds.
However, why doesn't the following imply a difference between Einsteinian STR and Lorentz?
Imagine we can build a spaceship which will travel at 0.995c. In the frame of a stationary observer, everyone agrees that the spaceship looks squished as it flies past (because of a perspective effect in Minkowski spacetime for STR, or because it actually is squished for Lorentz).
However, if I am actually on the ship then other things inside either should look squished (because they are - Lorentz) or they do not look squished (because all inertial frames are equivalent - Einstein). Now whenever I have seen this discussed one just reads that in Lorentz theory measuring rods are distorted too so I can't measure the effect. But surely if I'm going at 0.995c then things will just look distorted (spheres not being spherical etc) and I can tell the damned measuring rod is a lot shorter than it used to be (because it's now square, rather than a long rectangular metre rule).
So maybe it's because my eyes are distorted, or whatever - but isn't this dangerous? Being compressed to the thickness of a piece of cardboard can't be good for the human body surely..
What's the flaw here? All opinions gratefully received.
Cheers,
Zenith