Nahomi Kan

Deconstructing scalar QED at zero and finite temperature

Abstract. We calculate the effective potential for the WLPNGB in a world with a circular latticized extra dimension. The mass of the Wilson line pseudo-Nambu-Goldstone boson (WLPNGB) is calculated from the one-loop quantum effect of scalar fields at zero and finite temperature. We show that a series expansion by the modified Bessel functions is useful to calculate the one-loop effective potentials.

Divergences in quantum electrodynamics on a graph

We consider a model of quantum electrodynamics (QED) on a graph. The one-loop divergences in the model are investigated by use of the background field method.We consider a model of quantum electrodynamics (QED) on a graph as the generalization of dimensional deconstruction with the Abelian symmetry. Arbitrary structures of the theory space correspond to the graphs consisting of vertices and edges. The mass spectrum of the model is expressed in terms of eigenvalues of the Laplacian for the graph. We also find that physical massless scalar modes are associated with the fundamental tie set matrix on the graph. We further investigate the one-loop divergences in the model by use of the background field method.

Induced Gravity from Theory Space

The mass spectrum of a model constructed in a theory space is expressed in terms of eigenvalues of the Laplacian on the graph structure of the theory space. The nature of the one-loop UV divergence in the vacuum energy is then determined by only the degree matrix of the graph. Using these facts, we construct models of induced gravity that do not exhibit quadratic divergences at the one-loop level.

Shape of deconstruction

We construct a six-dimensional Maxwell theory using a latticized extra space, the continuum limit of which is a shifted torus recently discussed by Dienes. This toy model exhibits a correspondence between continuum theory and discrete theory, and gives a geometrical insight into theory-space model building.

Bulk fermion stars with new dimensions

Much effort has been devoted to the study of the phenomenology in particle physics with extra dimensions. We propose degenerate fermion stars with extra dimensions and study the features characterized by the size of the extra dimensions that should appear in their structure. We find that Kaluza-Klein excited modes arise for the larger scale of extra dimensions and examine the conditions under which different layers should be caused in the inside of the stars. We expound on how the extra dimensions affect the physical quantities.

Newtonian analysis of multiscalar boson stars with large self-couplings

We study solutions for boson stars in the multi-scalar field theory with global symmetry

Generic Scalar Potentials in Geometric Scalar Gravity

[U(1)]^N

Analytical study of charged boson stars with large scalar self-couplings

. The properties of the boson stars are investigated by the Newtonian approximation with the large coupling limit. Our purpose is to study the models bringing about exotic mass distributions which explain flat rotation curves of galaxies. We propose plausible models in which coupling matrices are associated with various graphs in graph theory.

Magnetic Monopoles in Multivector Boson Theories

AbstractWe discuss a generic form of the scalar potential appearing in the geometric scalar theory of gravity. We find the conditions on the potential by considering weak and strong gravity. The modified black hole solutions are obtained for generic potentials and the inverse problems on a black hole and on a spherical body (‘pseudo-gravastar’) are investigated.

Hybrid theory of gravity

We give good approximate analytic solutions for spherical charged boson stars in the large scalar-self-coupling limit in general relativity. We show that if the charge e and mass m of the scalar field nearly satisfy the critical relation