相关论文: Origin of Small Cosmological Constant in Brane-Wor…
Although the cosmological constant has primarily cosmological consequences, its smallness poses one of the basic problems in particle physics. Various attempts have been made to explain this mystery, but no satisfactory solution has been…
There appears to be no natural explanation for the cosmological constant's small size within the framework of local relativistic field theories. We argue that the recently-discussed framework for which the observable universe is identified…
We consider the cosmological evolution of a bulk scalar field and ordinary matter living on the brane world in the light of the constraints imposed by the matter dominated cosmological evolution and a small cosmological constant now. We…
We discuss the cosmological constant problem in the context of higher codimension brane world scenarios with infinite-volume extra dimensions. In particular, by adding higher curvature terms in the bulk action we are able to find smooth…
We investigate the physically accepted solutions of general Braneworld scenarios, scanning uniformly the associated parameter space. Without making any further assumptions we find that solutions which give "small" Hubble parameters on the…
The cosmology of branes undergoing the self-tuning mechanism of the cosmological constant is considered. The equations and matching conditions are derived in several coordinate systems, and an exploration of possible solution strategies is…
This work investigates the cosmology of a thick brane within the context of $f(\mathbb{Q})$ gravity, an extension of symmetric teleparallelism. Using a five-dimensional Friedmann-Lema\^itre-Robertson-Walker metric, we solve the field…
A simple model of the brane-world cosmology has been proposed, which is characterized by four parameters, the bulk cosmological constant, the spatial curvature of the universe, the radiation strength arising from bulk space-time and the…
We discuss how the fine-tuning of the cosmological constant enters brane world setups. After presenting the Randall Sundrum model as a prototype case, we focus on single brane models with curvature singularities which are separated from the…
We study a mechanism, inspired from the mechanism for generating the gauge hierarchy in Randall-Sundrum model, to investigate the cosmological constant problem. First we analyze the bulk cosmological constant and brane vacuum energies in RS…
We study a class of braneworlds where the cosmological evolution arises as the result of the movement of a three-brane in a five-dimensional static dilatonic bulk, with and without reflection symmetry. The resulting four-dimensional…
The cosmological constant problem and brane universes are reviewed briefly. We discuss how the cosmological constant problem manifests itself in various scenarios for brane universes. We review attempts - and their difficulties - that aim…
We point out several subtleties arising in brane-world scenarios of cosmological constant cancellation. We show that solutions with curvature singularities are inconsistent, unless the contribution to the effective four-dimentional…
We consider ``brane universe'' with nonzero tension in the models with large extra dimensions. We find exact solutions of higher-dimensional Einstein equations with single flat Minkowsky brane of arbitrary large tension (or brane…
There are many interesting issues in the brane world with a large/warped extra dimension. We focus on the cosmological aspects. We review the cosmological solutions of the brane world and how the conventional four-dimensional cosmology is…
In this manuscript we study the cosmological constant of a $(p+1)$-dimensional world, which lives in the higher dimensional bulk space. We assume the extra dimensions are compact on tori. We consider two cases: positive and negative bulk…
We discuss the possibility of a dynamical solution to the cosmological constant problem in the contaxt of six-dimensional Einstein-Maxwell theory. A definite answer requires an understanding of the full bulk cosmology in the early universe,…
Accelerating universe or the existence of a small and positive cosmological constant is probably the most pressing obstacle as well as opportunity to significantly improving the models of four-dimensional cosmology from fundamental theories…
The estimation of the cosmological constant in inflationary Brane New World models is done. It is shown that basically it is quite large, of the same order as in anomaly-driven inflation. However, for some fine-tuning of bulk gravitational…
We study the value of cosmological constant in de Sitter brane embedded in five dimensions with positive, vanishing and negative bulk cosmological constant. In the case of negative bulk cosmological constant, we show that not zero but tiny…