Yusuke Kimura

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SATOSHI ISO a)c) 1 , YUSUKE KIMURA a)b) 2 , KANJI TANAKA a)c) 3 and KAZUNORI WAKATSUKI a)d) 4 Abstract We derive a noncommutative U(1) and U(n) gauge theory on the fuzzy sphere from a three dimensional matrix model by expanding the model around a classical solution of the fuzzy sphere. Chern-Simons term is added in the matrix model to make the fuzzy sphere(More)
We consider a reduced model of four-dimensional Yang-Mills theory with a mass term. This matrix model has two classical solutions, two-dimensional fuzzy sphere and two-dimensional fuzzy torus. These classical solutions are constructed by embedding them into three or four dimensional flat space. They exist for finite size matrices, that is, the number of the(More)
Matrix descriptions of higher dimensional spherical branes are investigated. It is known that a fuzzy 2k-sphere is described by the coset space SO(2k + 1)/U (k) and has some extra dimensions. It is shown that a fuzzy 2k-sphere is comprised of n k(k−1) 2 spherical D(2k − 1)-branes and has a fuzzy 2(k − 1)-sphere at each point. We can understand the(More)
D0-branes are unstable in the presence of an R-R field strength background. A fuzzy two-sphere is classically stable under such a background, this phenomenon being called the Myers effect. We analyze this effect from the viewpoint of tachyon condensation. It is explicitly shown that a fuzzy two-sphere is realized by the condensation of tachyons which appear(More)
This paper proposes a framework for analyzing legal sentences including itemized or referential expressions. Thus far, we have developed a system for translating legal documents into logical formu-lae. Although our system basically converts words and phrases in a target sentence into predicates in a logical formula, it generates some useless predicates for(More)
It is known that noncommutative Yang-Mills is equivalent to IIB matrix model with a noncommutative background, which is interpreted as a twisted reduced model. In non-commutative Yang-Mills, long range interactions can be seen in nonplanar diagrams after integrating high momentum modes. These interactions can be understood as block-block interactions in the(More)