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Comment on: Topological Invariants, instantons, and the chiral anomaly on spaces with torsion

Dirk Kreimer·Eckehard W. Mielke
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Abstract

In Riemann-Cartan spacetimes with torsion only its axial covector piece $A$ couples to massive Dirac fields. Using renormalization group arguments, 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 $d^\star A$, as has been claimed in a recent paper [PRD 55, 7580 (1997)].

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Dirk Kreimer, Eckehard W. Mielke. 1999-04-28. Comment on: Topological Invariants, instantons, and the chiral anomaly on spaces with torsion. https://doi.org/10.1103/physrevd.63.048501

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