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arXiv · 0708.2426

Emergent Gravity from Noncommutative Gauge Theory

Harold Steinacker
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Abstract

We show that the matrix-model action for noncommutative U(n) gauge theory actually describes SU(n) gauge theory coupled to gravity. This is elaborated in the 4-dimensional case. The SU(n) gauge fields as well as additional scalar fields couple to an effective metric G_{ab}, which is determined by a dynamical Poisson structure. The emergent gravity is intimately related to noncommutativity, encoding those degrees of freedom which are usually interpreted as U(1) gauge fields. This leads to a class of metrics which contains the physical degrees of freedom of gravitational waves, and allows to recover e.g. the Newtonian limit with arbitrary mass distribution. It also suggests a consistent picture of UV/IR mixing in terms of an induced gravity action. This should provide a suitable framework for quantizing gravity.

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Harold Steinacker. 2007-12-19. Emergent Gravity from Noncommutative Gauge Theory. https://doi.org/10.1088/1126-6708%2F2007%2F12%2F049

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