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arXiv · hep-th/9403191

Plane Gravitational Waves in String Theory

I. Antoniadis·N. A. Obers
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Abstract

We analyze the coset model $(E_2^c \ti E_2^c)/E_2^c$ and construct a class of exact string vacua which describe plane gravitational waves and their duals, generalizing the plane wave background found by Nappi and Witten. In particular, the vector gauging describes a two-parameter family of singular geometries with two isometries, which is dual to plane gravitational waves. In addition, there is a mixed vector-axial gauging which describes a one-parameter family of plane waves with five isometries. These two backgrounds are related by a duality transformation which generalizes the known axial-vector duality for abelian subgroups.

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I. Antoniadis, N. A. Obers. 1994-03-31. Plane Gravitational Waves in String Theory. https://doi.org/10.1016/0550-3213(94)90147-3

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