Petr Horava attempts to start at this paper a small quantum gravity theory, like Loop Quantum Gravity, except that he, according to his words: http://arxiv.org/abs/0901.3775v1 "In analogy with Yang-Mills, we are motivated to look for a “small” theory of quantum gravity in 3+1 dimensions, decoupled from strings. One attempt to construct such a “small” theory is offered by loop quantum gravity. In this paper, we present a new strategy for addressing this problem. Compared to the previous approaches to quantum gravity, the novelty of our approach is that it takes advantage of theoretical concepts developed in recent decades in condensed matter physics, in particular in the theory of quantum critical phenomena." I haven't yet read the paper, but I am really surprised he didn't use any string theory for that! Perhaps that can be embended in string theory, but nonetheless, he didn't even adressed that in the conclusion. For those who don't know Petr Horava, he is one of the greatest string theorists.