What if the CERN LHC experiments prove the existence of multiple dimensions?

Question

What effect would that have on the Theory of General Relativity?

Answer 1

That depends on whether they exist!

Sensible answer...probably not. Even if they do exist, and several of the most popular theories consider them likely, they may only be visible at energy scales above what the LHC will see. But they might be bigger than we think, which would be quite exciting.

I don't know a lot about GR but I don't think merely proving more dimensions exist would have a big effect. If the properties were investigated further they may or may not turn out to be compatible with GR. At least one of quantum mechanics or GR has to be wrong or incomplete anyway as they're not compatible.

Answer 2

We already know that multiple dimensions exist, we have three spatial dimensions and a fourth time dimension which we experience on a daily basis.

Answer 3

It wouldn't necessarily change it fundamentally at all.  But it would be a little piece of evidence to support the notion that gravity is just another force that is mediated by another quantum field, the graviton.  Which means that Einstein's model of gravity as curving space/time isn't really fundamental, but just a mathematical trick that happens to work well at low energy scales.

--No, it wouldn't prove that the gravitational field is quantized.  But the principle motivation for posutlating extra dimensions is to explain why gravity couples so weakly.  If you believe that gravity is completely different from the other forces, you wouldn't really see much need for the extra dimensions in the first place.