2011/04/01 by David Baumgartner, Baumgartner, David, Urs Wenger +1
Physics and Astronomy · #FOS: Physical sciences #High Energy Physics - Lattice (hep-lat) #hep-lat
paper · pdf · doi:10.48550/arxiv.1104.0213
14 pages, 4 figures, Talks presented at the XXVIII International Symposium on Lattice Field Theory, Lattice2010, Villasimius, Italy, June 14-19, 2010
arxiv created 2011/04/01 · arxiv updated 2011/04/04
Simulations of supersymmetric models on the lattice with (spontaneously) broken supersymmetry suffer from a fermion sign problem related to the vanishing of the Witten index. We propose a novel approach which solves this problem in low dimensions by formulating the path integral on the lattice in terms of fermion loops. The formulation is based on the exact hopping expansion of the fermionic action and allows the explicit decomposition of the partition function into bosonic and fermionic contributions. We devise a simulation algorithm which separately samples the fermionic and bosonic sectors, as well as the relative probabilities between them. The latter then allows a direct calculation of the Witten index and the corresponding Goldstino mode. Finally, we present results from simulations on the lattice for the spectrum and the Witten index for N=2 supersymmetric quantum mechanics.