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arXiv · 0909.2173

Notes on unoriented D-brane instantons

Massimo Bianchi·Marine Samsonyan
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Abstract

In the first lecture, we discuss basic aspects of worldsheet and penta-brane instantons as well as (unoriented) D-brane instantons, which is our main focus here, and threshold corrections to BPS-saturated couplings. The second lecture is devoted to non-perturbative superpotentials generated by `gauge' and `exotic' instantons living on D3-branes at orientifold singularities. In the third lecture we discuss the interplay between worldsheet and D-string instantons on $T^4/Z_2$. We focus on a 4-fermi amplitude, give Heterotic and perturbative Type I descriptions, and offer a multi D-string instanton interpretation. We conclude with possible interesting developments.

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Massimo Bianchi, Marine Samsonyan. 2009-09-11. Notes on unoriented D-brane instantons. https://doi.org/10.1142/s0217751x09048022

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