The underlying thought here is that at low relativistic speeds all objects are subjected to emf radiation from all directions.

This is basically the sum of all the radiation (light, infra-red, x-rays, gamma rays etc) hitting us from all sides from distant stars/quasars etc. According to Lorentz these passing fields must exert some force effects on the atomic particles (excepting maybe neutrons). The results of these forces are, in steady state, balanced from all sides (much like we don't feel the massive pressure of air at 14psi pressing upon us since it's balanced on all sides).

However, as an object's speed increases in any direction, then there must be a change in this balance. The object's leading edge would be experiencing more directed emf at higher frequencies while the trailing end is experiencing them at lower frequencies (lower energies). This is similar to the Doppler effect or red shift.

The question then becomes, can it be proven, or dis-proven (or has someone already tried to) that this doppler-like effect or compression of emf energy contributes to the relativistic changes to that same mass as it approaches C?

One piece of astronomical evidence for this would be the observation that galaxies at the universe's far edge appear to be leaving us at > C. Could it be that those galaxies are no longer running into to emf repulsion from their leading edge (farthest from us) and thus the speed of light is no longer imposed upon them by emf?

Any references to research on this topic are appreciated.

  • $\begingroup$ I submit that the asymmetry of Lorenz forces would be a product of the fact that an object moving in any direction at a high percentage of the speed of light would be approaching the speed that emf radiation in that same direction is already travelling, while simultaneously colliding with incoming radiation more and more frequently. Is there any reason to believe this differential would not cause an asymmetrical force as well? Are there any experiments which show this is not the case? $\endgroup$ – mcstar Dec 29 '14 at 22:41

The only naturally occurring symmetry breaking radiation of this kind is the CMB. Unless you are talking about charged particles of more than approx. 1e19eV energy (in the CMB rest system), the effects are negligible, as far as I know. For those ultrahigh energy particles, however, this so called Greisen–Zatsepin–Kuzmin limit (GZK limit) forms a cosmic fog that does slow them down, so that the highest energy cosmic rays have to be produced in our cosmic neighborhood (probably within the local supercluster), or they would not reach us. Below that energy limit (charged particle) cosmic rays are mostly effected by galactic magnetic fields.

In addition there is at least one rather old paper about the exposure of interstellar rockets traveling at up to 90% of the speed of light to dust and interstellar gas. The abrasion and heating due to collisions does increase quite a bit as a macroscopic body approaches the speed of light, so this may set a practical limit to travel near the speed of light. The effect of light, x-ray, gamma ray and cosmic ray sources are basically negligible compared to the dust and gas, because those particles are already traveling either at or close to the speed of light, so adding a slightly relativistic boost to that will only increase their energy by a trivial amount. Hitting gas and, much worse, dust particles, on the other hand, poses a non-trivial challenge to the hull integrity of relativistic projectiles.

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  • $\begingroup$ Are you saying that radiation from stars does not exert a Lorentz force on electrons for example? Aren't all radiation/light sources in the galaxy exerting forces on the charged particles as they pass? I would assume that velocity in any direction approaching C changes the symmetry of this radiation. As we near C, the relative speed of energy approaching from the rear decreases, while increasing at the leading edge. It would seem that this could create an asymmetrical force on the matter itself tending to stretch and rip it apart. $\endgroup$ – mcstar Dec 17 '14 at 18:55
  • $\begingroup$ I wouldn't use classical electrodynamics for these calculations but QFT. The cross sections of a visible photon and a relativistic electron (and much more so a proton) are pretty small (and space is pretty dark!), so it just doesn't do much to the radiation that exists in space. Even magnetic fields of a few nT are much more disruptive. One can, of course, scatter relativistic particles on ultra strong laser pulses. The Europeans are planning to build three accelerator facilities to do just that in the next decade. $\endgroup$ – CuriousOne Dec 17 '14 at 19:03
  • $\begingroup$ I think I understand. Basically approximately static magnetic fields (presumably from stars and planets) have a far greater affect on matter at high speed than any radiation or emf. Interesting thought. Does this imply that speed of light/relativistic affects are caused primarily by magnetic fields? $\endgroup$ – mcstar Dec 17 '14 at 19:34
  • $\begingroup$ @mcstar: The speed of light (in our current understanding) is a fundamental natural constant of spacetime. It basically regulates the ratio between distance in space and distance in time (in our choice of units). It's that ratio from which the relativistic properties of matter follow, not the other way around. It isn't the properties of electromagnetic fields that cause the speed of light, but this property of spacetime causes the structure of electromagnetic fields. $\endgroup$ – CuriousOne Dec 18 '14 at 1:55

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