# Why do we need a theory of quantum gravity

I've been wondering, why does the world need a theory of quantum gravity? What questions would be solved if such a theory was discovered?

What does a theory of quantum gravity mean for blackholes, if anything?

Try to be quite indepth about the questions rather than something like "It will tell us what happened at t = 0" :P

rubi
$$R_{\mu\nu}-\frac{1}{2}g_{\mu\nu} R = 8\pi T_{\mu\nu} \,\text{.}$$