%0 Journal Article
%T D-instantons and twistors
%+ Laboratoire de Physique Théorique et Astroparticules (LPTA)
%+ Laboratoire de Physique Théorique et Hautes Energies (LPTHE)
%+ Institut de Physique Théorique - UMR CNRS 3681 (IPHT)
%+ Institute for Theoretical Physics [Utrecht]
%A Alexandrov, Sergey
%A Pioline, Boris
%A Saueressig, Frank
%A Vandoren, Stefan
%< avec comité de lecture
%Z 08-073
%@ 1126-6708
%J Journal of High Energy Physics
%I Springer
%N 03
%P 044
%8 2009-03-06
%D 2009
%Z 0812.4219
%R 10.1088/1126-6708/2009/03/044
%K D-instantons
%K string theory
%K quaternionic geometry
%Z Physics [physics]/High Energy Physics - Theory [hep-th]
%Z Physics [physics]/Mathematical Physics [math-ph]
%Z Mathematics [math]/Mathematical Physics [math-ph]Journal articles
%X Finding the exact, quantum corrected metric on the hypermultiplet moduli space in Type II string compactifications on Calabi-Yau threefolds still poses an outstanding open problem. We address this issue by relating the quaternionic-Kahler metric on the hypermultiplet moduli space to the complex contact geometry on its twistor space. In this framework, Euclidean D-brane instanton contributions are captured by contact transformations between different locally flat patches. We derive those by recasting the previously known A-type D2-instanton corrections in the language of contact geometry, covariantizing the result under electro-magnetic duality, and using mirror symmetry. As a result, we are able to express the effects of all D-instantons in Type II compactifications concisely as a sum of dilogarithm functions. We conclude with some comments on the relation to microscopic degeneracies of four-dimensional BPS black holes and to the wall-crossing formula of Kontsevich and Soibelman, and on the form of the yet unknown NS5-brane instanton contributions.
%G English
%L hal-00349154
%U https://hal.science/hal-00349154
%~ IN2P3
%~ CEA
%~ UNIV-PARIS7
%~ UPMC
%~ LPTA
%~ CNRS
%~ LPTHE
%~ UNIV-MONTP2
%~ DSM-IPHT
%~ TDS-MACS
%~ UPMC_POLE_2
%~ UNIV-MONTPELLIER
%~ CEA-DRF
%~ SORBONNE-UNIVERSITE
%~ SU-SCIENCES
%~ UNIV-PARIS
%~ SU-TI
%~ GS-MATHEMATIQUES
%~ GS-PHYSIQUE
%~ ALLIANCE-SU
%~ UM1-UM2