2015/02/28 by Eric A. Bergshoeff, Keshav Dasgupta, Renata Kallosh +2
Physics and Astronomy · #hep-th #hep-ph
paper · pdf · doi:10.1007/jhep05(2015)058
published as JHEP 1505:058, 2015 · 25 pages; v2: added clarifying comments and one reference
arxiv created 2015/05/07 · arxiv updated 2015/05/20
The role of the \rm D3 brane in providing de Sitter vacua with spontaneously broken supersymmetry in the KKLT construction is clarified. The first step in this direction was explained in arXiv:hep-th/0301240, arXiv:hep-th/0308055: it was shown there that in the GKP background the bosonic contributions to the vacuum energy from the DBI and WZ term cancel for a D3 brane, but double for a \rm D3 brane, leading to de Sitter vacua. The next step was taken in arXiv:1411.1121 where the analogous mechanism of the doubling (cancelation) of the \rm D3 (D3) DBI and WZ terms was discovered in the presence of Volkov-Akulov fermions living on the brane, in a flat supergravity background. Here we confirm this mechanism of doubling/cancelation for the \rm D3/D3 brane in the GKP supergravity background preserving N=1, d=4 supersymmetry. We find that imaginary self-dual G(3) flux of type (2,1) nicely removes the SU(3) fermion triplet by giving it a large mass, while leaving the Volkov-Akulov goldstino, which is the SU(3) singlet, massless. This makes the de Sitter landscape in D-brane physics clearly related to de Sitter vacua in effective d=4 supergravity with a nilpotent multiplet and spontaneously broken supersymmetry.