Continuous Model

[Jonnyb42]

Has it been considered to instead of quantizing gravity, and incorporating gravity into the quantum theory, but rather incorporating the other three forces into relativity?

[Kevin_Axion]

All of the other forces namely, The Strong Nuclear force and Electroweak force are quantized into and described by Quantum Field Theories: SU(3)xSU(2)xU(1) (The Standard Model). A Quantum Field Theory is a combination of Quantum Mechanics and Special Relativity. Regardless of that point quantizing gravity is necessary to understand the fundamental ideas of the Universe such as where the Universe came from and Planck Scale Physics in which the Energy Levels require that gravity be incorporated. Your approach doesn't address those ideas which are necessary.

[S.Daedalus]

There's this paper, 'Quantizing Geometry or Geometrizing the Quantum?', which follows an approach somewhat along these lines: http://arxiv.org/abs/1004.2879

[inflector]

Regardless of that point quantizing gravity is necessary to understand the fundamental ideas of the Universe such as where the Universe came from and Planck Scale Physics in which the Energy Levels require that gravity be incorporated. Your approach doesn't address those ideas which are necessary.

Why is quantization of gravity necessary to understand planck-scale physics?

Don't we just need a theory of gravity that doesn't have singularities at that level?

I suppose that implies that there is some sort of short-distance cutoff where the gravity equations stop acting like a 1/r^2 force. But is quantization the only method that will generate this behavior?

[Kevin_Axion]

Why is quantization of gravity necessary to understand planck-scale physics?

Don't we just need a theory of gravity that doesn't have singularities at that level?

I suppose that implies that there is some sort of short-distance cutoff where the gravity equations stop acting like a 1/r^2 force. But is quantization the only method that will generate this behavior?

It is so described in the first paragraph: http://en.wikipedia.org/wiki/Planck_scale

And a theory without singularities at Planck Scale is ultimately a theory of quantum gravity.