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arXiv · 0912.1433

Generalized Chern-Simons Modified Gravity in First-Order Formalism

Ümit Ertem·Özgür Açık
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Abstract

We propose a generalization of Chern-Simons (CS) modified gravity in first-order formalism. CS modified gravity action has a term that comes from the chiral anomaly which is Pontryagin invariant. First-order CS modified gravity is a torsional theory and in a space-time with torsion the chiral anomaly includes a torsional topological term called Nieh-Yan invariant. We generalize the CS modified gravity by adding the Nieh-Yan term to the action and find the effective theory. We compare the generalized theory with the first-order CS modified gravity and comment on the similarities and differences.

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Ümit Ertem, Özgür Açık. 2009-12-08. Generalized Chern-Simons Modified Gravity in First-Order Formalism. https://doi.org/10.1007/s10714-012-1483-8

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