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arXiv · 1612.03966

On Background Independence and Duality Invariance in String Theory

Olaf Hohm
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Abstract

Closed string theory exhibits an O(D,D) duality symmetry on tori, which in double field theory is manifest before compactification. I prove that to first order in $α'$ there is no manifestly background independent and duality invariant formulation of bosonic string theory in terms of metric, b-field and dilaton. To this end I use O(D,D) invariant second order perturbation theory around flat space to show that the unique background independent candidate expression for the gauge algebra at order $α'$ is inconsistent with the Jacobi identity. A background independent formulation exists instead for frame variables subject to $α'$-deformed frame transformations (generalized Green-Schwarz transformations). Potential applications for curved backgrounds, as in cosmology, are discussed.

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Olaf Hohm. 2017-03-30. On Background Independence and Duality Invariance in String Theory. https://doi.org/10.1103/physrevlett.118.131601

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