In quantum field theory, gauge gravitation theory is the effort to extend Yang–Mills theory, which provides a universal description of the fundamental interactions, to describe gravity. It should not be confused with the related but distinct gauge theory gravity.
The first gauge model of gravity was suggested by R. Utiyama in 1956 just two years after birth of the gauge theory itself, However, the initial attempts to construct the gauge theory of gravity by analogy with the gauge models of internal symmetries encountered a problem of treating general covariant transformations and establishing the gauge status of a pseudo-Riemannian metric (a tetrad field).
The Quark-Gluon Plasma [QGP] is described in terms of gauge-gravity duality by charged, locally asymptotically AdS black holes. This duality cannot however be expected to account for an arbitrarily large domain in the quark-matter phase diagram: one does not for example expect that it will provide a good description at extremely high temperatures [where a fully "stringy" account of the bulk will be necessary]. We argue that, likewise, the gauge-gravity duality itself points to a bound on its applicability in the direction of large chemical potentials, though in most cases at values far beyond experimental access. However, the upper bound can, in some circumstances, depend strongly on the amount of angular momentum present, and it is conceivable that this bound could be probed by experiments designed to produce rapidly rotating quark-gluon plasmas with large chemical potentials.
Read more : http://en.wikipedia.org/wiki/Gauge_gravitation_theory ||http://arxiv.org/pdf/1403.3258
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