相关论文: Zero-brane approach to quantization of biscalar fi…
We consider, in five dimensions, the effective action from heterotic string which includes quantum gravity corrections up to (a')^2. The expansion, in the string frame, is in terms of |a'R|, where R is the scalar curvature and uses the…
The possibility of neutral, brane-like solutions in a higher dimensional setting is discussed. In particular, we describe a supersymmetric solution in six dimensions which can be interpreted as a "three-brane" with a non-compact transverse…
We address the group classification problem for gravitational field equations within the context of brane-world cosmology, considering the presence of a bulk scalar field. Our investigation revolves around a five-dimensional spacetime, with…
Bouncing non-singular isotropic cosmological solutions are investigated in a simple model of scalar-tensor gravity. New families of such solutions are found and their properties are presented and analyzed using an effective potential as the…
The main purpose of the present paper is analyzing magnetic brane solutions of cubic quasi-topological gravity in the presence of a linear electromagnetic Maxwell field and a nonlinear electromagnetic Born-Infeld field. We show that the…
We study the cosmology for a two branes model in a space-time of five dimensions where the extra coordinate is compactified on an orbifold. The hidden brane is filled with a real scalar field endowed with a quadratic potential that behaves…
In this paper, we present a new class of charged rotating black brane solutions in the higher dimensional Brans-Dicke-Born-Infeld theory and investigate their properties. Solving the field equations directly is a non-trivial task because…
The effects of higher order gravity terms on a dilatonic brane world model are discussed. For a single positive tension flat 3-brane, and one infinite extra dimension, we present a particular class of solutions with finite 4-dimensional…
We derive a new analytic solution of $(n+1)$-dimensional Brans-Dikce-Maxwell theory in the presence of a potential for the scalar field, by applying a conformal transformation to the dilaton gravity theory. These solutions describe…
We show that a four-dimensional equation of state for a cosmological constant term arises from a perfect fluid in the bulk in the context of a gravity model where the scalar curvature is non-minimally coupled to the perfect fluid Lagrangian…
We explore the possibility of a non-singular bounce in our universe from a warped braneworld scenario with dynamical branes and a non-zero brane cosmological constant. Such models naturally incorporate a scalar sector known as the radion…
One of the interesting open problems in the cosmological framework is applying quantum physics to the whole universe, consistently. Although different conceptual aspects of quantum cosmology are still very much alive, till now, all the…
In this paper we consider $(n+1)$-dimensional cosmological model with scalar field and antisymmetric $(p+2)$-form. Using an electric composite $Sp$-brane ansatz the field equations for the original system reduce to the equations for a…
Recently, Pani, Sotiriou, and Vernieri explored a new theory of gravity by adding nondynamical fields, i.e., gravity with auxiliary fields [Phys. Rev. D 88, 121502(R) (2013)]. In this gravity theory, higher-order derivatives of matter…
We study pairs of 4d N=1 supersymmetric gauge theories that share the same vacuum moduli space and the same chiral field content, encoded by a common quiver, but differ in their superpotentials. These theories arise as worldvolume theories…
The character of quantum corrections to the gravitational action of a conformally invariant field theory for a self-interacting scalar field on a manifold with boundary is considered at third loop-order in the perturbative expansion of the…
We study the cosmology of a three-brane in a specific five-dimensional scalar-gravity (i.e. soft-wall) background, known as the linear dilaton background. We discover that the Friedmann equation of the brane-world automatically contains a…
We derive the exact supergravity profile for the twisted scalar field emitted by a system of fractional D3 branes at a Z2 orbifold singularity supporting N=2 quiver gauge theories with unitary groups and bifundamental matter. At the…
We investigate homogeneous and isotropic cosmological models in scalar-tensor theories of gravity where two scalar fields are nonminimally coupled to the geometry. Exact solutions are found, by Noether symmetries, depending on the form of…
In a recent paper we proposed a mechanism for a continuous transition between a contracting Ekpyrotic phase and the Standard Big Bang phase of expansion: the bounce is generated by an S-brane which represents the effects of higher mass…