English

Noncommutative D=4 gravity coupled to fermions

High Energy Physics - Theory 2009-07-22 v1 General Relativity and Quantum Cosmology Mathematical Physics math.MP

Abstract

We present a noncommutative extension of Einstein-Hilbert gravity in the context of twist-deformed space-time, with a \star-product associated to a quite general triangular Drinfeld twist. In particular the \star-product can be chosen to be the usual Groenewald-Moyal product. The action is geometric, invariant under diffeomorphisms and centrally extended Lorentz \star-gauge transformations. In the commutative limit it reduces to ordinary gravity, with local Lorentz invariance and usual real vielbein. This we achieve by imposing a charge conjugation condition on the noncommutative vielbein. The theory is coupled to fermions, by adding the analog of the Dirac action in curved space. A noncommutative Majorana condition can be imposed, consistent with the \star-gauge transformations. Finally, we discuss the noncommutative version of the Mac-Dowell Mansouri action, quadratic in curvatures.

Keywords

Cite

@article{arxiv.0902.3817,
  title  = {Noncommutative D=4 gravity coupled to fermions},
  author = {Paolo Aschieri and Leonardo Castellani},
  journal= {arXiv preprint arXiv:0902.3817},
  year   = {2009}
}

Comments

19 pages, LaTeX

R2 v1 2026-06-21T12:14:17.130Z