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arXiv · 0909.0689

Topics on the geometry of D-brane charges and Ramond-Ramond fields

Fabio Ferrari Ruffino
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Abstract

In this paper we discuss some topics on the geometry of type II superstring backgrounds with D-branes, in particular on the geometrical meaning of the D-brane charge, the Ramond-Ramond fields and the Wess-Zumino action. We see that, depending on the behaviour of the D-brane on the four non-compact space-time directions, we need different notions of homology and cohomology to discuss the associated fields and charge: we give a mathematical definition of such notions and show their physical applications. We then discuss the problem of corretly defining Wess-Zumino action using the theory of p-gerbes. Finally, we recall the so-called *-problem and make some brief remarks about it.

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Fabio Ferrari Ruffino. 2009-10-19. Topics on the geometry of D-brane charges and Ramond-Ramond fields. https://doi.org/10.1088/1126-6708%2F2009%2F11%2F012

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