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arXiv · 0712.0977

The Plebanski action extended to a unification of gravity and Yang-Mills theory

Lee Smolin
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Abstract

We study a unification of gravity with Yang-Mills fields based on a simple extension of the Plebanski action to a Lie group G which contains the local lorentz group. The Coleman-Mandula theorem is avoided because the theory has no global spacetime symmetry. This may be applied to Lisi's proposal of an E8 unified theory, giving a fully E8 invariant action. The extended form of the Plebanski action suggests a new class of spin foam models.

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Lee Smolin. 2008-07-25. The Plebanski action extended to a unification of gravity and Yang-Mills theory. https://doi.org/10.1103/physrevd.80.124017

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