arXiv subjects

Masato Ito

Publications and source records attributed to Masato Ito.

23 records · Page 2Linked to original sources

arXiv2002

Newton's law in braneworlds with an infinite extra dimension

We study the behavior of the four$-$dimensional Newton's law in warped braneworlds. The setup considered here is a $(3+n)$-brane embedded in $(5+n)$ dimensions, where $n$ extra dimensions are compactified and a dimension is infinite. We show that the wave function of gravity is described in terms of the Bessel functions of $(2+n/2)$-order and that estimate the correction to Newton's law. In particular, the Newton's law for $n=1$ can be exactly obtained.

hep-th↗

arXiv2001

Five-Dimensional Warped Geometry with a Bulk Scalar Field

We explore the diversity of warped metric function in five-dimensional gravity including a scalar field and a 3-brane. We point out that the form of the function is determined by a parameter introduced here. For a particular value of the parameter, the warped metric function is smooth without having a singularity, and we show that the bulk cosmological constant have a upper bound and must be positive and that the lower bound of five-dimensional fundamental scale is controlled by both the brane tension and four-dimensional effective Planck scale. The general warp factor obtained here may relate to models inspired by SUGRA or M-theory.

hep-th↗

arXiv2001

Various Types of Five-Dimensional Warp Factor and Effective Planck Scale

Based on the assumption that the warp factor of four-dimensional spacetime and the one of fifth dimension are tied through a parameter $α$, we consider five-dimensional gravity with a 3-brane coupled to a bulk scalar field. For arbitrary value of $α$, the form of the warp factor is implicitly determined by hypergeometric function. Concretely, we show that the warp factor becomes explicit form for appropriate value of $α$, and study the relation between four-dimensional effective Planck scale and the brane tension. This setup allows the possibility of extending the diversity of brane world.

hep-th↗

arXiv2001

Warped Geometry in Higher Dimensions with an Orbifold Extra Dimension

We solve the Einstein equations in higher dimensions with warped geometry where an extra dimension is assumed to have orbifold symmetry $S^{1}/Z_{2}$. The setup considered here is an extension of the five-dimensional Randall-Sundrum model to $5+D$ dimensions, and hidden and observable branes are fixed on the orbifold. It is assumed that the brane tension (self-energy) of each brane with $(4+D)$-dimensional spacetime is anisotropic and that the warped metric function of the four dimensions is generally different from that of the extra $D$ dimensions. We point out that the forms of the warped metric functions and the relations between the tensions of two branes depend on the integration constant appearing in the Einstein equations as well as on the sign of the bulk cosmological constant.

hep-th↗

arXiv2001

The $μ$-Problem and Seesaw-type Mechanism in the Higgs Sector

We explore a new solution to the $μ$-problem. In the scenario of SUSY-breaking mediation through anti-generation fields, we find that the $Bμ$ term has its origin in a seesaw-type mechanism as well as in a loop diagram through gauge interactions. It is shown that the dominant contributions to the $Bμ$ term are controlled by the flavor symmetry in the model.

hep-ph↗