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On singularities of spherically symmetric backgrounds in string theory

A. A. Tseytlin
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Abstract

We suggest that for singular rotationally invariant closed string backgrounds which need sources for their support at the origin (in particular, for special plane waves and fundamental strings) certain `trivial' \a'-corrections (which are usually ignored since in the absence of sources they can be eliminated by a field redefinition) may play an important role eliminating the singularities in the exact solutions. These corrections effectively regularize the source delta-function at the \a'-scale. We demonstrate that similar smearing of the singularity of the leading-order point-source solution indeed takes place in the open string theory.

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A. A. Tseytlin. 1995-09-08. On singularities of spherically symmetric backgrounds in string theory. https://doi.org/10.1016/0370-2693(95)01228-7

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