Comment Re:Possible exception to the "law"... (Score 2) 194
the assumption that the current physical laws and constants were true then. By definition, they weren't - the four fundamental forces did not assert themselves until a finite period of time
If they didn't "assert themselves," does that imply that they did exist? I think that this way of speaking is a little confusing, because we believe that current "laws" represent special cases of more general laws, rather than different laws entirely.
If nothing had mass at the instant of the Big Bang, how does Einstein's theory of Relativity apply? Objects become infinitely massless as their speed approaches c?
Massless particles inherently move at c. They can't be accelerated or decelerated because they have no inertia, although they do have momentum.
As far as we know, this was just as true right after the big bang. Particles, or field excitations or whatever, had no mass, and moved at c. They did have energy, and an energy density, and therefore were gravitationally attracted. This attraction would be described by quantum gravity, instead of General Relativity.
Once the particles acquired mass via the Higgs mechanism (probably at or about the same time that the modern-day forces became completely separated), the universe was still an ultra-hot quark plasma, so the newly massive particles still moved very rapidly. Just not at c.