Masakatsu Kenmoku

Pseudo Dirac Neutrino

There is a growing interest in the neutrino masses. Theoretically, there is much freedom in neutrino mass patterns in contrast to quarks and charged leptons because neutrinos are in general considered Majorana particles. Experimentally, the v-oscillation!) and the /3/3 decay2),3) give serious constraints to neutrino masses and their mixing scheme. A special case where there are degeneracies of Majorana neutrino masses has recently been interesting. If the degeneracy happens as a consequence of the special symmetry in the mass matrix, a pair of degenerate Majorana neutrinos may form a Dirac neutrino. This Dirac neutrino is called the pseudo Dirac (PD) neutrino,4)-6) if the symmetry of the mass matrix is not the symmetry of the weak interaction. That is, the lepton number assigned to this Dirac neutrino is not conserved in the weak interaction and thus the mass degeneracy is removed by the higher order perturbation of the weak interaction. A PD neutrino has recently drawn special attention due to the tight neutrino mass bound obtained from the analysis of the /3/3 decay,2),3)

Scalar field contribution to rotating black hole entropy

Scalar field contribution to entropy is studied in arbitrary D dimensional one parameter rotating spacetime by semiclassical method. By introducing the zenithal angle dependent cutoff parameter, the generalized area law is derived. The non-rotating limit can be taken smoothly and it yields known results. The derived area law is then applied to the Banados-Teitelboim-Zanelli (BTZ) black hole in (2+1) dimension and the Kerr-Newman black hole in (3+1) dimension. The generalized area law is reconfirmed by the Euclidean path integral method for the quantized scalar field. The scalar field mass contribution is discussed briefly.

Normal modes and the no zero mode theorem of scalar fields in BTZ black hole spacetime

The eigenfunctions for normal modes of scalar fields in BTZ black hole spacetime are studied. The orthonormal relations among them are derived. Quantization for scalar fields is done, and particle number, energy and angular momentum are expressed by the creation and annihilation operators. The allowed physical normal mode region is studied on the basis of the no zero mode theorem. Its implications for statistical mechanics is also studied.

de Broglie-Bohm interpretation for the wave function of quantum black holes

We study the quantum theory of the spherically symmetric black holes. The theory yields the wave function inside the apparent horizon, where the role of time and space coordinates is interchanged. The de Broglie-Bohm interpretation is applied to the wave function and then the trajectory picture on the minisuperspace is introduced in the quantum as well as the semi-classical region. Around the horizon large quantum fluctuations on the trajectories of metrics

Generalized Einstein theory on solar and Galactic scales

U

Eigenvalue Problem of Scalar Fields in BTZ Black Hole Spacetime

and

Classical and quantum solutions and the problem of time in cosmology

V

De Broglie-Bohm Interpretation for Analytic Solutions of the Wheeler-DeWitt Equation in Spherically Symmetric Space-Time

appear in our model, where the metrics are functions of time variable

ROTATION CURVES OF SPIRAL GALAXIES AND LARGE-SCALE STRUCTURE OF THE UNIVERSE UNDER GENERALIZED EINSTEIN ACTION

T

Analytic solutions of the Wheeler-DeWitt equation in spherically symmetric space-time

and are expressed as