arXiv subjects

Ewald Roessl

Publications and source records attributed to Ewald Roessl.

3 recordsLinked to original sources

arXiv2005

Topological defects and gravity in theories with extra dimensions

Various solutions to higher-dimensional Einstein equations coupled to a series of physically different sources are considered and their properties of localization of gravity discussed. A numerical example of a solution to the Einstein equations coupled to a set of scalar and gauge fields is given: a 3-brane realized as a 't Hooft-Polyakov monopole residing in a 7-dimensional space-time. Finally we describe a model which resembles the Randall-Sundrum II model with respect to its properties of gravity localization but with the advantage that the underlying space-time manifold is geodesically complete.

hep-th↗

arXiv2002

Localizing gravity on a 't Hooft-Polyakov monopole in seven dimensions

We present regular solutions for a brane world scenario in the form of a 't Hooft-Polyakov monopole living in the three-dimensional spherical symmetric transverse space of a seven-dimensional spacetime. In contrast to the cases of a domain-wall in five dimensions and a string in six dimensions, there exist gravity-localizing solutions for both signs of the bulk cosmological constant. A detailed discussion of the parameter space that leads to localization of gravity is given. A point-like monopole limit is discussed.

hep-th↗

arXiv2000

Living Inside a Hedgehog: Higher-dimensional Solutions that Localize Gravity

We consider spherically symmetric higher-dimensional solutions of Einstein's equations with a bulk cosmological constant and n transverse dimensions. In contrast to the case of one or two extra dimensions we find no solutions that localize gravity when $n\geq 3$, for strictly local topological defects. We discuss global topological defects that lead to the localization of gravity and estimate the corrections to Newton's law. We show that the introduction of a bulk ``hedgehog'' magnetic field leads to a regular geometry and localizes gravity on the 3-brane with either a positive, zero or negative bulk cosmological constant. The corrections to Newton's law on the 3-brane are parametrically the same as for the case of one transverse dimension.

hep-th↗