Optical theory of gravity

UPDATE Sept 14, 2018: the optical theory apparently gives wrong predictions for the phase of the wave function of a particle. See blog post Sept 12, 2018.

...

Isaac Newton had thoughts about unifying optics and gravity:

Eric Baird: Relativity in Curved Spacetime: Life Without Special Relativity

Since gravity bends light and a refractive material also bends light, there is an analogy between them.

Suppose that we have an observer in a gravitational potential well, say, on the surface of Earth. Suppose he is holding two electric charges in his hands and he has to use energy to pull them one meter apart. If another observer far away in space sends him this energy as light, the light will be blueshifted and the observer on Earth thinks he receives more energy than was sent by the space observer.

From the point of view of the space observer, the Coulomb force on Earth appears to be weaker than in space. The same holds for every force, also the Newton force of gravity itself.

The weakening of forces is the reason why clocks tick slower and light travels slower in a gravitational potential well.

Conjecture 1. The real geometry of spacetime is Minkowski everywhere, also in a gravitational potential well. The apparent curving of the spacetime geometry is due to the weakening of effective forces in the gravitational potential well. Weakening of the Coulomb force causes the speed of electromagnetic waves to slow down.

We call the above conjecture the optical theory of gravity.

Conjecture 2. Gravitation is just the Newton force of gravity, which propagates at the global speed of light in the Minkowski space. The global speed of light is not affected by gravitational potential wells but is the same everywhere in the Minkowski space. The Newton force is completely analogous to the Coulomb force.

Conjecture 2 resolves a problem of general relativity: how fast does the information of a changed position of a black hole travel? It takes an infinite time for light to travel from the horizon to the environment. How do the black holes in a binary black hole know the position of each other? Our solution is that the local speed of light does not affect the speed of the information that is carried in the Newton force.

The apparent curvature of spacetime is the result of differences in the optical density, or refractive index, of empty space. The density is not the same to every direction. In the Schwarzschild global coordinates, the speed of light is less in the radial direction than in the tangential direction. In optics, this phenomenon is called birefringenge. Crystals have refractive indexes that depend on the direction of light relative to the crystal lattice.

Conjecture 3. The Newton force causes polarization of virtual particles of positive and negative mass-energy (gravity charge) in empty space, just as the Coulomb force causes polarization of virtual electron-positron pairs in empty space. This polarization makes all forces to be weaker in the radial direction than in the tangential direction in the Schwarzschild geometry. The space around a gravitating mass is like a crystal whose lattice has the radial direction as a special direction.

Polarization causes a round hydrogen atom to squeeze in the radial direction in the Schwarzschild solution. All measuring rods become shorter in the radial direction but not in the tangential direction.

Open problem 4. Is quantum gravity easy to formulate in optical gravity? Is there a renormalization problem? How does the weakening of forces in a gravitational potential well affect quantum field theory?

Open problem 5. How do we model mathematically the polarization of virtual gravity charges in empty space?


Open problem 6. The horizon of a forming black hole would be optically infinitely dense, that is, all forces have zero strength and the speed of light is zero. Particles with non-zero rest mass will reflect from the horizon and repeatedly bounce from it. If the particles are electrically charged, they will radiate their energy away in photons? What is the end result of this process? Can this explain the relativistic jets that shoot from astronomical black holes?


Would the reflection of waves and particles from a forming event horizon break the Strong equivalence principle 4 of our blog post below?

http://meta-phys-thoughts.blogspot.fi/2018/04/does-hawking-radiation-exist.html

A freely falling laboratory would observe mysterious reflection of photons and other particles when it is close to the horizon. Eventually, the particles that form the laboratory would themselves be reflected. The laboratory would be destroyed before it reaches the forming horizon.

UPDATE: this may be the first experimental evidence that supports optical gravity:

http://meta-phys-thoughts.blogspot.fi/2018/04/echoes-of-gravitational-waves-are.html