Yasuhiro Abe

Multigluon amplitudes, N = 4 constraints, and the Wess-Zumino-Witten model

Classical N=4 Yang-Mills theory is defined by the superspace constraints. We obtain a solution of a subset of these constraints and show that it leads to the maximally helicity violating amplitudes. The action which leads to the solvable part of the constraints is a Wess-Zumino-Witten action on a suitably extended superspace. The non-maximally helicity violating tree amplitudes can also be expressed in terms of this action.

Noncommutative gravity: Fuzzy sphere and others

Gravity on noncommutative analogues of compact spaces can give a finite mode truncation of ordinary commutative gravity. We obtain the actions for gravity on the noncommutative two-sphere and on the noncommutative

Construction of fuzzy S**4

{\mathbf{CP}}^{2}

An interpretation of multigraviton amplitudes

in terms of finite dimensional

Emergence of longitudinal 7-branes and fuzzy S{sup 4} in compactification scenarios of M(atrix) theory

(N\ifmmode\times\else\texttimes\fi{}N)

Fuzzy S4 and Its Construction

matrices. The commutative large N limit is also discussed.

Construction of fuzzy S{sup 4}

We construct a fuzzy

Construction of fuzzyS4

S^4

Construction of Fuzzy Spaces and Their Applications to Matrix Models

, utilizing the fact that

Construction of fuzzy S4

{\bf CP}^3