Any scientist who can't explain to an eight-year old what he is doing is a charlatan.
—Kurt Vonnegut, Cat's Cradle
Because the hyperbolic metric Einstein created allows us to define how much space-time can change the amount of mass(and vice versa!). And this only works if the speed of light is constant—that's actually the God-like conceptual leap Einstein took when realizing the Michelson-Morley experiment implied much bigger things about space, time, mass and gravity, and not just mere light speed.
Also, it keeps several other super-important constraints in place too. That's the problem with gravity—it's more like an infinite Jenga puzzle and anything you add to the explanation must not contradict dozens of other old physics experiments about things having nothing to do with gravity. We can't throw out all the other stuff we do know after all. Like the constancy of the speed of light in any reference frame. And the conservation of energy.
And Maxwell's electrodynamic equations. And a bunch of other specific experiments I don't even know much about.
I don't know how much of thermodynamics has been "relativized", but gravity can't contradict the laws of thermodynamics either. It's actually comforting that the world of thermodynamics is so tiny, cold, deals with such a large number of "particles"(ensembles), and is built from insanely complex mathematical machinery that we probably have no hope of ever devising an experiment that could say anything meaningful about gravity in terms of thermodynamics. (I so hope that I'm very wrong here.)
However, Gravity is famously in contradiction with Quantum Mechanics, though I haven't yet progressed far enough in either to be able to say specifically what the contradiction is. I suspect it's just the lack of a math "bridge" between Relativity, which is built up from calculus, differential forms, tensors, Rienmannian geometry, the calculus of variations and weird ways QM uses linear algebra, eigenvalues, infinite bounded operators and insane algebraic concepts like von Neumann algebras to setup infinite matrices of probabilities that map back to the periodic, bounded solutions of the Schrödinger wave equation that tell us what the energy levels of some physics experiment must be.
Oh and the model of gravity has to be able to fit in well with any new stuff we discover too. Being able to pull off all of that is why I place Einstein in the pantheon of geniuses! He's kind of like a one-armed man who holds off an entire army of swordsmen using only a pocket knife.
Any scientist who can't explain to an eight-year old what he is doing is a charlatan.
Because the hyperbolic metric Einstein created allows us to define how much space-time can change the amount of mass(and vice versa!). And this only works if the speed of light is constant—that's actually the God-like conceptual leap Einstein took when realizing the Michelson-Morley experiment implied much bigger things about space, time, mass and gravity, and not just mere light speed.Also, it keeps several other super-important constraints in place too. That's the problem with gravity—it's more like an infinite Jenga puzzle and anything you add to the explanation must not contradict dozens of other old physics experiments about things having nothing to do with gravity. We can't throw out all the other stuff we do know after all. Like the constancy of the speed of light in any reference frame. And the conservation of energy. And Maxwell's electrodynamic equations. And a bunch of other specific experiments I don't even know much about.
I don't know how much of thermodynamics has been "relativized", but gravity can't contradict the laws of thermodynamics either. It's actually comforting that the world of thermodynamics is so tiny, cold, deals with such a large number of "particles"(ensembles), and is built from insanely complex mathematical machinery that we probably have no hope of ever devising an experiment that could say anything meaningful about gravity in terms of thermodynamics. (I so hope that I'm very wrong here.)
However, Gravity is famously in contradiction with Quantum Mechanics, though I haven't yet progressed far enough in either to be able to say specifically what the contradiction is. I suspect it's just the lack of a math "bridge" between Relativity, which is built up from calculus, differential forms, tensors, Rienmannian geometry, the calculus of variations and weird ways QM uses linear algebra, eigenvalues, infinite bounded operators and insane algebraic concepts like von Neumann algebras to setup infinite matrices of probabilities that map back to the periodic, bounded solutions of the Schrödinger wave equation that tell us what the energy levels of some physics experiment must be.
Oh and the model of gravity has to be able to fit in well with any new stuff we discover too. Being able to pull off all of that is why I place Einstein in the pantheon of geniuses! He's kind of like a one-armed man who holds off an entire army of swordsmen using only a pocket knife.