Some Remarks on Gravity in Noncommutative Spacetime and a New Solution to the Structure Equations
نویسنده
چکیده
In this paper, starting from the common foundation of Connes’ noncommutative geometry ( NCG)[1, 2, 3, 4], various possible alternatives in the formulation of a theory of gravity in noncommutative spacetime are discussed in detail. The diversity in the final physical content of the theory is shown to be the consequence of the arbitrariness in each construction steps. As an alternative in the last step, when the structure equations are to be solved, a minimal set of contraints on the torsion and connection is found to determine all the geometric notions in terms of metric. In the Connes-Lott model of noncommutative spacetime, in order to keep the full spectrum of the discretized Kaluza-Klein theory [5], it is necessary to include the torsion in the generalized Einstein-Hilbert-Cartan action. PACS. 04.20.Jb, 04.40. +c, 11.15. -q, 14.80.Hv ∗E-mail: [email protected]
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