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arXiv · hep-th/0207235

Does the Tachyon Matter?

Alex Buchel·Peter Langfelder·Johannes Walcher
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Abstract

We study time-dependent solutions of Einstein-Maxwell gravity in four dimensions coupled to tachyon matter--the Dirac-Born-Infeld Lagrangian that provides an effective description of a decaying tachyon on an unstable D-brane in string theory. Asymptotically, the solutions are similar to the recently studied space-like brane solutions and carry S-brane charge. They do not break the Lorentzian R-symmetry. We study the tachyon matter as a probe in such a background and analyze its backreaction. For early/late times, the tachyon field has a constant energy density and vanishing pressure as in flat space. On the other hand, at intermediate times, the energy density of the tachyon diverges and produces a space-like curvature singularity.

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Alex Buchel, Peter Langfelder, Johannes Walcher. 2002-08-14. Does the Tachyon Matter?. https://doi.org/10.1006/aphy.2002.6306

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