Maldacena proved in 1997, that there is a weak-strong duality between quantum gravity in D+1 dimensions and Yang-Mills theory formulated on and Anti De Sitter space in D dimensions. Seminal articles (must read):

https://arxiv.org/abs/hep-th/9812012

http://lanl.arxiv.org/abs/hep-th/9711200

http://lanl.arxiv.org/abs/hep-th/9804085

I hope this helps!