Akio Hattori

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Christopher ALLDAY (University of Hawaii) Cohomological Aspects of Symplectic Lie Group Actions Abstract. Let G be a compact connected Lie group acting symplecticly on a closed symplectic manifold (M,ω). Many interesting results concerning such actions can be proved quite easily using the cohomological methods pioneered by P. A. Smith, A. Borel and many(More)
Multi-fan is an analogous notion of fan in toric theory. Fan is a combinatorial object associated to a toric variety. Multi-fan is associated to an orbifold with an action of half the dimension of the orbifold. In this paper the equivariant elliptic genus and the equivariant orbifold elliptic genus of multi-fans are defined and their character formulas are(More)
We introduce the notion of a multi-fan. It is a generalization of that of a fan in the theory of toric varieties in algebraic geometry. Roughly speaking a toric variety is an algebraic variety with an action of an algebraic torus of the same dimension as that of the variety, and a fan is a combinatorial object associated with the toric variety.(More)
The recent financial crisis has prompted academia, country authorities, and international bodies to study quantitative tools to monitor the financial system, especially systemic risk measures. This paper aims to outline these measures and apply them to Japan’s financial system. The paper demonstrates that they are effective tools for monitoring the(More)
Let M be a closed almost complex manifold on which a compact connected Lie group G acts non-trivially. If the first Chern class of M is divisible by an integer N greater than 1, then its equivariant elliptic genus φ(M) of level N is rigid, i.e., it is constant as a virtual character of G. This result was predicted by Witten [W] and proved by Taubes [T],(More)
This article is a continuation of [HM2]. Elliptic genera for manifolds introduced by Ochanine and other people has a remarkable feature called rigidity. If the circle group acts non-trivially on a closed almost complex (or more generally stably almost complex) manifold whose first Chern class is divisible by a positive integer N greater than 1, then its(More)
We fabricated silver iodide (AgI)-coated silver hollow waveguides to transmit a wide range of infrared (IR) light. Silver-clad stainless steel pipes were used as a supporting pipe. Since this type of metallic hollow waveguide has high mechanical strength and heat resistance, it is suitable as a rigid lightwave probe for various applications such as dental(More)