相关论文: Five-Dimensional Warped Geometry with a Bulk Scala…

In this work, we investigate the presence of thick branes modeled by a single scalar field with Born-Infeld-like dynamics. We consider the 4-dimensional metric being Minkowski, de Sitter or anti-de Sitter. We obtain the field equations and…

We investigate the localization of metastable four-dimensional gravity around a bent dilatonic brane, embedded into a five-dimensional space, that exists only up to distances sufficiently small compared to a crossover scale. Far from such…

A five dimensional brane cosmology with non-minimally coupled scalar field to gravity has been considered in a Jordan-Brans-Dicke frame. We derive an effective four dimensional field equations on a 3+1 dimensional brane where the fifth…

In this paper we derive the effective theory for a stabilized five-dimensional warped geometry, addressing several outstanding issues in this derivation. These include allowing for a non-zero 4d cosmological constant, accounting for…

We derive two classes of brane-world solutions arising in the presence of a bulk scalar field. For static field configurations, we adopt a time-dependent, factorizable metric ansatz that allows for radion stabilization. The solutions are…

Gravitational properties of a hedge-hog type topological defect in two extra dimensions are considered in General Relativity employing a vector as the order parameter. The developed macroscopic theory of phase transitions with spontaneous…

The method of four-dimensional Causal Dynamical Triangulations provides a background-independent definition of the sum over geometries in quantum gravity, in the presence of a positive cosmological constant. We present the evidence…

We provide an explicit example of a higher-dimensional model describing a non-supersymmetric spectrum of 4D particles of mass M, whose 4D geometry -- {\em including loop effects} -- has a curvature that is of order R ~ m_KK^4/M_p^2, where…

We consider compactifications of six dimensional gravity in four dimensional Minkowski or de Sitter space times a two dimensional sphere, S^2. As has been recently pointed out, it is possible to introduce 3-branes in these backgrounds with…

In brane-world theory in five dimensions, the bulk metric is usually written in gaussian coordinates, where $g_{4\mu} = 0$ and $g_{44} = - 1$. However, the choice $g_{44} = - 1$ is an external condition, not a requirement of the field…

Bimetric theory describes gravitational interactions in the presence of an extra spin-2 field. Previous work has suggested that its cosmological solutions are generically plagued by instabilities. We show that by taking the Planck mass for…

We discuss a new solution, admitting the existence of dS_{4} branes, in five-dimensional Brans-Dicke theory. It is shown that, due to a special form of a bulk scalar field potential, for certain values of the model parameters the effective…

We study brane-world solutions of five-dimensional supergravity in singular spaces. We exhibit a self-tuned four-dimensional cosmological constant when five-dimensional supergravity is broken by an arbitrary tension on the brane-world. The…

We consider a quintessential sector realized on a hidden brane with a tiny warp factor, which implies a small value of the effective four-dimensional cosmological constant through an equation of motion for the quintessential scalar.

Particle physics has evolved in the past decade through evaluating the consequences of experimental measurements as well as exploiting theoretical tools that permit exploration of new model building and cosmological possibilities.…

A bimetric gravity model with a variable speed of light is shown to be in agreement with the results reported from the Planck satellite in 2013. The predicted scalar mode spectral index is $n_s\approx 0.96$ and its running is…

We consider non-linear gravitational models with a multidimensional warped product geometry. Particular attention is payed to models with quadratic scalar curvature terms. It is shown that for certain parameter ranges, the extra dimensions…

We present a toy model of a generic five-dimensional warped geometry in which the 4D graviton is not fully localized on the brane. Studying the tensor sector of metric perturbation around this background, we find that its contribution to…

We investigate braneworld models in the presence of the several scalar fields with generalized dynamics. A new mechanism to control the internal structure of brane in modified gravity is used to induce changes in the models in the presence…

The recent observation by CDF collaboration has disclosed a modification in the mass of the $W$ boson. In this regard we show that this modification in the mass of the $W$ boson can be well explained in the background of a 6-dimensional…