Showing papers by "Yuji Tachikawa published in 2004"
TL;DR: In this paper, the authors extended the graviphoton-corrected prepotential of 5D pure U(N) super Yang-Mills, which was originally proposed by Nekrasov, by incorporating the effect of the 5D Chern-Simons term.
Abstract: We extend the graviphoton-corrected prepotential of 5D pure U(N) super Yang-Mills, which was originally proposed by Nekrasov, by incorporating the effect of the 5D Chern-Simons term. This extension allows us to reproduce by a gauge theory calculation the partition functions of corresponding topological A-model on local toric Calabi-Yau manifolds XmN for all m = 0,1,...,N. The original proposal corresponds to the case m = 0.
97 citations
TL;DR: In this article, the D = 4 N = 1 supergravity model was used for string theory and it was shown that the slow-roll parameter can be sufficiently small despite the non-minimal Kahler potential of the model.
Abstract: The slow-roll inflation is a beautiful paradigm, yet the inflaton potential can hardly be sufficiently flat when unknown gravitational effects are taken into account. However, the hybrid inflation models constructed in D = 4 N = 1 supergravity can be consistent with N = 2 supersymmetry, and can be naturally embedded into string theory. This article discusses the gravitational effects carefully in the string model, using D = 4 supergravity description. We adopt the D3--D7 system of Type IIB string theory compactified on K3 x T^2/Z_2 orientifold for definiteness. It turns out that the slow-roll parameter can be sufficiently small despite the non-minimal Kahler potential of the model. The conditions for this to happen are clarified in terms of string vacua. We also find that the geometry obtained by blowing up singularity, which is necessary for the positive vacuum energy, is stabilized by introducing certain 3-form fluxes.
81 citations
TL;DR: In this paper, the authors extended the graviphoton-corrected prepotential of five-dimensional pure U(N) super Yang-Mills, which was originally proposed by Nekrasov, by incorporating the effect of the fivedimensional Chern-Simons term.
Abstract: We extend the graviphoton-corrected prepotential of five-dimensional pure U(N) super Yang-Mills, which was originally proposed by Nekrasov, by incorporating the effect of the five-dimensional Chern-Simons term. This extension allows us to reproduce by a gauge theory calculation the partition functions of corresponding topological A-model on local toric Calabi-Yau manifolds X^m_N for all m=0,1,...,N. The original proposal corresponds to the case m=0.
59 citations
13 citations