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arXiv · 0807.4703

Topologically Massive Gravity at the Chiral Point is Not Unitary

Gaston Giribet·Matthew Kleban·Massimo Porrati
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Abstract

A recent paper [arXiv:0801.4566] claims that topologically massive gravity contains only chiral boundary excitations at a particular value of the Chern-Simons coupling. On the other hand, propagating bulk degrees of freedom were found even at the chiral point in [arXiv:0803.3998]. The two references use very different methods, making comparison of their respective claims difficult. In this letter, we use the method of [arXiv:0801.4566] to construct a tower of propagating bulk states satisfying standard AdS boundary conditions. Our states have finite norm, with sign opposite to that of right-moving boundary excitations. Our results thus agree with [arXiv:0803.3998] and disagree with [arXiv:0801.4566].

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Gaston Giribet, Matthew Kleban, Massimo Porrati. 2008-08-15. Topologically Massive Gravity at the Chiral Point is Not Unitary. https://doi.org/10.1088/1126-6708%2F2008%2F10%2F045

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