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Closed strings from decaying D-branes

Neil Lambert·Hong Liu·Juan Maldacena
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Abstract

We compute the emission of closed string radiation from homogeneous rolling tachyons. For an unstable decaying D$p$-brane the radiated energy is infinite to leading order for $p\leq 2$ and finite for $p>2$. The closed string state produced by a decaying brane is closely related to the state produced by D-instantons at a critical Euclidean distance from $t=0$. In the case of a D0 brane one can cutoff this divergence so that we get a finite energy final state which would be the state that the brane decays into.

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Neil Lambert, Hong Liu, Juan Maldacena. 2007-02-05. Closed strings from decaying D-branes. https://doi.org/10.1088/1126-6708%2F2007%2F03%2F014

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