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arXiv · 1902.04108

T-branes and defects

Fernando Marchesano·Raffaele Savelli·Sebastian Schwieger
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Abstract

We study T-branes on compact Kaehler surfaces, in the presence of fields localised at curves. If such fields are treated as defects, their vevs induce delta-function sources for the 7-brane background, possibly leading to profiles with poles. We find that the presence of defect sources relaxes the constraints on globally well-defined T-brane configurations, avoiding the obstruction to building them on surfaces of positive curvature. Profiles with poles can be understood, from a 4d viewpoint, as non-trivial vevs for massive modes induced by the defects, and come with their own set of constraints. In the special case of fields localised on a self-intersection curve, we show how to retrieve the Hitchin system with defects from an ordinary global one with enhanced symmetry.

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Fernando Marchesano, Raffaele Savelli, Sebastian Schwieger. 2019-02-11. T-branes and defects. https://doi.org/10.1007/jhep04(2019)110

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