29 research outputs found
D-instanton sums for matter hypermultiplets
We calculate some non-perturbative (D-instanton) quantum corrections to the
moduli space metric of several (n>1) identical matter hypermultiplets for the
type-IIA superstrings compactified on a Calabi-Yau threefold, near conifold
singularities. We find a non-trivial deformation of the (real) 4n-dimensional
hypermultiplet moduli space metric due to the infinite number of D-instantons,
under the assumption of n tri-holomorphic commuting isometries of the metric,
in the hyper-K"ahler limit (i.e. in the absence of gravitational corrections).Comment: 11 pages, no figure