SL(2,C) Gravity with Complex Vierbein and Its Noncommutative Extension
Abstract
We show that it is possible to formulate gravity with a complex vierbein based on SL(2,C) gauge invariance. The proposed action is a four-form where the metric is not introduced but results as a function of the complex vierbein. This formulation is based on the first order formalism. The novel feature here is that integration of the spin-connection gauge field gives rise to kinetic terms for a massless graviton, a massive graviton with the Fierz-Pauli mass term, and a scalar field. The resulting theory is equivalent to bigravity. We then show that by extending the gauge group to GL(2,C} the formalism can be easily generalized to apply to a noncommutative space with the star product. We give the deformed action and derive the Seiberg-Witten map for the complex vierbein and gauge fields.
Cite
@article{arxiv.hep-th/0309166,
title = {SL(2,C) Gravity with Complex Vierbein and Its Noncommutative Extension},
author = {Ali H. Chamseddine},
journal= {arXiv preprint arXiv:hep-th/0309166},
year = {2009}
}
Comments
Minor corrections. The noncommutative action in section 3 is simplified. Version to appear in Physical Review D