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arXiv · 1407.0708

Green-Schwarz mechanism and $\alpha'$-deformed Courant brackets

Olaf Hohm·Barton Zwiebach
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Abstract

We establish that the unusual two-form gauge transformations needed in the Green-Schwarz anomaly cancellation mechanism fit naturally into an $\alpha'$-deformed generalized geometry. The algebra of gauge transformations is a consistent deformation of the Courant bracket and features a nontrivial modification of the diffeomorphism group. This extension of generalized geometry emerged from a `doubled $\alpha'$-geometry', which provides a construction of exactly gauge and T-duality invariant $\alpha'$ corrections to the effective action.

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Olaf Hohm, Barton Zwiebach. 2014-07-02. Green-Schwarz mechanism and $\alpha'$-deformed Courant brackets. https://doi.org/10.1007/jhep01(2015)012

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