Generalized Mom-structures and ideal triangulations of 3-manifolds with non-spherical boundary

The so-called Mom-structures on hyperbolic cusped 3-manifolds without boundary were introduced by Gabai, Meyerhoff, and Milley, and used by them to identify the smallest closed hyperbolic manifold. In this work we extend the notion of a Mom-structure to include the case of 3-manifolds with non-empty boundary that does not have spherical components. We then describe a certain relation between such generalized Mom-structures, called protoMom-structures, internal on a fixed 3-manifold N, and ideal triangulations of N; in addition, in the case of non-closed hyperbolic manifolds without annular cusps, we describe how an internal geometric protoMom-structure can be constructed starting from Epstein-Penner or Kojima decomposition. Finally, we exhibit a set of combinatorial moves that relate any two internal protoMom-structures on a fixed N to each other.Comment: 38 pages, 19 figues; exposition style changed, particularly in Section 2.2; minor content changes in Section 2.

Gravitational Correction in Neutrino Oscillations

We investigate the quantum mechanical oscillations of neutrinos propagating in weak gravitational field. The correction to the result in the flat space-time is derived.Comment: 5 pages, Latex file without figures , accepted for publication in Modern Physics Letters

Financial contracts and strategic customer exclusion

The paper studies an incentive contract in a monopolistic and duopolistic credit market where borrowers are different in risk. One lender is in an advantaged position with respect to the other due to past relations with the borrowers. The features of the equilibrium contract are investigated. It is shown that the equilibrium contract drastically changes between the monopolistic and the duopolistic situations and are sensitive to other parameters. In some cases, the superior lender strategically yields borrowers, especially the better ones to the opponent lender

Quasi-toroidal oscillations in rotating relativistic stars

Quasi-toroidal oscillations in slowly rotating stars are examined in the framework of general relativity. The oscillation frequency to first order of the rotation rate is not a single value even for uniform rotation unlike the Newtonian case. All the oscillation frequencies of the r-modes are purely neutral and form a continuous spectrum limited to a certain range. The allowed frequencies are determined by the resonance condition between the perturbation and background mean flow. The resonant frequency varies with the radius according to general relativistic dragging effect.Comment: 4 pages, Latex file without figure, submitted to Mon. Not. R. Astron. So