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arXiv · hep-th/0412096

Instability of Tachyon Supertube in Type IIA Godel Spacetime

Wung-Hong Huang
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Abstract

We study the tachyon supertube probes in a type IIA supergravity background which is a stringy-like Gödel spacetime and contains closed timelike curve. In the case of small value of $f$, which is a parameter of the background, we use the Minahan-Zwiebach tachyon action to obtain a single regular tube solution and argue that the tube is a BPS D2-brane. However, we find that the fluctuation around the tube configuration has a negative-energy mode. This means that the tachyon supertube, despite being a BPS configuration, develops an instability in the pathological spacetime with closed timelike curve which violates the causality.

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Wung-Hong Huang. 2005-05-25. Instability of Tachyon Supertube in Type IIA Godel Spacetime. https://doi.org/10.1016/j.physletb.2005.04.031

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