|MadSci Network: Physics|
I do not think that relativity (special or general theory of relativity) is the Holy Grail of physics. One reason for that is that it is not compatible with quantum mechanics. That means that gravity is a classical theory. It takes no quantum corrections into account. Furthermore, up to now no attempt to quantise gravity has been successful.
In the mentioned article, the author merely rewrites some formulae and inserts them into each other. Nothing is gained. What is claimed to be the "supersymmetry of light" to me just seems to be the fact that you can associate a wavelength to a massive particle. Due to quantum mechanics particles (or even molecules) in some situations behave like waves. This has been measured even. Double slit experiments with particles have really shown an interference pattern, as light or waterwaves do. But this fact is completely unrelated to the theory of relativity. The mixing up a few things does not mean that a connection on a deeper level is established.
We can ask: What could be the Holy Grail of physics? Probably a good answer
is the theory of everything, i.e. a theory that is capable of describing
all known interactions at once (gravity, strong and weak nuclear force,
electromagnetic force). Relativity is only kinematics, it does not describe
forces but only free motion of bodies. In case of general relativity,
gravity is not described as a force but as curvature of space-time. General
relativity then describes free motion in curved space-time.
So the goal would be to find or to create a in some sense consistent quantum theory, which has general relativity as a limit, and also contains the other forces.
I hope this helps,
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