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arXiv · 1506.05789

BMS, String Theory, and Soft Theorems

Steven G. Avery·Burkhard U. W. Schwab
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Abstract

We study the action of the BMS group in critical, bosonic string theory living on a target space of the form $\mathbb{M}^{d}\times C$. Here $M^{d}$ is $d$-dimensional (asymptotically) flat spacetime and $C$ is an arbitrary compactification. We provide a treatment of generalized Ward--Takahashi identities and derive consistent boundary conditions for any $d$ from string theory considerations. Finally, we derive BMS transformations in higher dimensional spacetimes and show that the generalized Ward--Takahashi identity of BMS produces Weinberg's soft theorem in string theory.

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Steven G. Avery, Burkhard U. W. Schwab. 2015-06-18. BMS, String Theory, and Soft Theorems. https://doi.org/10.1103/physrevd.93.026003

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