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arXiv · gr-qc/9704051

Chiral Anomaly in Contorted Spacetimes

E. W. Mielke·D. Kreimer
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Abstract

The Dirac equation in Riemann-Cartan spacetimes with torsion is reconsidered. As is well-known, only the axial covector torsion $A$, a one-form, couples to massive Dirac fields. Using diagrammatic techniques, we show that besides the familiar Riemannian term only the Pontrjagin type four-form $dA\wedge dA$ does arise additionally in the chiral anomaly, but not the Nieh-Yan term $d ^* A$, as has been claimed recently. Implications for cosmic strings in Einstein-Cartan theory as well as for Ashtekar's canonical approach to quantum gravity are discussed.

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E. W. Mielke, D. Kreimer. 1997-04-18. Chiral Anomaly in Contorted Spacetimes. https://doi.org/10.1023/a%3A1026653314045

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