Smooth quotients of bi-elliptic surfaces

We consider the quotient X of bi-elliptic surface by a finite automorphism group. If X is smooth, then it is a bi-elliptic surface or ruled surface with irregularity one. As a corollary any bi-elliptic surface cannot be Galois covering of projective plane, hence does not have any Galois embedding

Galois embedding of K3 surface --abelian case--

We study Glois embeddings of K3 surfaces in the case where the Galois groups are abelian. We show several properties of K3 surfaces concerning the Galois embeddings. In particular, if the Galois group G is abelian, then G is isomorphic to Z/4Z, Z/6Z or Z/2Z\oplusZ/2Z\oplusZ/2Z and S is a smooth complete intersection of hypersurfaces. Further, we state the detailed structure of such surfaces

Nonequilibrium identities of granular vibrating beds

We derive the integral fluctuation theorem around a nonequilibrium stationary state for frictionless and soft core granular particles under an external vibration achieved by a balance between an external vibration and inelastic collisions. We also discuss the connection between the integral fluctuation theorem and the generalized Green-Kubo formula.Comment: 15 pages, no figures to be published in Comptes rendus - M\'ecanique as Proceedings of EuroMech2012 at Graz, Austri

Generalized Green-Kubo formula for a dissipative quantum system

A generalized Green-Kubo formula is derived for a quantum dissipative system of driven Brownian particle, in which the coupling between the system and the environment is linear. The structure is essentially the same as that for the generalized Green-Kubo formula for driven granular particles. It is demonstrated that the correction to the conventional Green-Kubo formula is zero for a free Brownian particle.Comment: 12 pages, no figures. Prog. Theor. Phys. Suppl. (to be published

Calabi-Yau Compactification of Type-IIB string and a Mass Formula of the Extreme Black Holes

Recently proposed mechanism of the black hole condensation at conifold singularity in type II string is an interesting idea from which we can interpret the phase of the universal moduli space of the string vacua. It might also be expected that the true physics is on the conifold singularity after supersymmetry breaking. We derive a mass formula for the extreme black holes caused by the self-dual 5-form field strength, which is stable and supersymmetric. It is shown that the formula can be written by the moduli parameters of Calabi-Yau manifold and can be calculated explicitly.Comment: 10 gages, late

Sextic variety as Galois closure variety of smooth cubic

Let V be a nonsingular projective algebraic variety of dimension n. Suppose there exists a very ample divisor D such that D^n=6 and dim H^0(V, O(D))=n+3. Then, (V, D) defines a D_6-Galois embedding if and only if it is a Galois closure variety of a smooth cubic in P^{n+1} with respect to a suitable projection center such that the pull back of hyperplane of P^n is linearly equivalent to D