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arXiv · 0901.1666

Classical solutions for exotic instantons?

Marco Billo'·Marialuisa Frau·Laurent Gallot·Alberto Lerda·Igor Pesando
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Abstract

We consider the D7/D(--1) system in Type I' as a prototypical "exotic" brane instanton. With respect to systems such as the D3/D(-1) ones, which correspond to gauge instantons in four dimensions, exotic systems lack the bosonic mixed moduli w of the ADHM construction, related to the instanton size, and their possible field-theoretical interpretation as classical solutions is an important open question. For the system at hand, we propose that it corresponds to the point-like limit of the eight-dimensional so-called SO(8) instanton solution. This configuration is a solution of the quartic term of the non-abelian D7 action, i.e., the term which stays finite in the limit in which alpha' goes to zero with the string coupling fixed that preserves the D(-1) effects. As a necessary consistency condition, we check that the next order term in the non-abelian effective action vanishes on the SO(8) solution so that the limit we take is well-defined.

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Marco Billo', Marialuisa Frau, Laurent Gallot, Alberto Lerda, Igor Pesando. 2009-03-04. Classical solutions for exotic instantons?. https://doi.org/10.1088/1126-6708%2F2009%2F03%2F056

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