搜索结果: 1-15 共查到“星系与宇宙学 Gravity”相关记录15条 . 查询时间(0.106 秒)
Topics in gravity and supergravity
The singular Black hole formation Magnetic monopoles. Gravity magnetic False vacuum
2014/12/9
In the first part of the thesis we study the formation of non-singular black holes in the collapse of magnetic monopoles. We employ a thin shell approximation model for a gravitating magnetic monople ...
Equation of State for Dark Energy in Modified Gravity Theories
Modified theories of gravity Dark energy Cosmology
2012/2/21
We explore the equation of state (EoS) for dark energy $w_{\mathrm{DE}}$ in modified gravitational theories to explain the current accelerated expansion of the universe. We explicitly demonstrate that...
We model the chameleon effect on cosmological statistics for the modified gravity f(R) model of cosmic acceleration. The chameleon effect, required to make the model compatible with local tests of gra...
Pre-big bang collapsing universe from modern Kaluza-Klein theory of gravity
Pre-big bang collapsing universe modern Kaluza-Klein theory gravity
2011/10/18
We study the collapse of the universe described by a scalar field spherically symmetric collapse of a system described by a massless scalar field from a 5D Riemann-flat canonical metric, on which we m...
Reconstruction of f(R, T) gravity describing matter dominated and accelerated phases
Reconstruction gravity describing dominated accelerated phases
2011/10/12
We investigate the cosmological reconstruction in modified f(R,T) gravity, where R is the Ricci scalar and T the trace of the stress-energy tensor. Special attention is attached to the case in which t...
Domain wall solution in $F(R)$ gravity and variation of the fine structure constant
solution gravity variation fine structure
2011/10/18
We construct a domain wall solution in $F(R)$ gravity. We first compare a scalar field theory having a runaway type potential with a corresponding scalar field theory obtained through a conformal tran...
Beyond Einstein: Cosmological Tests of Model Independent Modified Gravity
Beyond Einstein: Cosmological Model Independent Modified Gravity
2011/10/8
Model-independent parametrisations of modified gravity have attracted a lot of attention over the past few years; numerous combinations of experiments and observables have been suggested to constrain ...
Nonlocal gravity and its cosmological manifestations
Nonlocal gravity cosmological manifestations
2011/10/18
We suggest a class of generally covariant ghost-free nonlocal gravity models generating de Sitter or Anti-de Sitter background with an arbitrary value of the effective cosmological constant and featur...
Towards a fully consistent parameterization of modified gravity
fully consistent parameterization modified gravity
2011/9/27
There is a distinct possibility that current and future cosmological data can be used to constrain Einstein's theory of gravity on the very largest scales. To be able to do this in a model-independent...
Towards a fully consistent parameterization of modified gravity
fully consistent parameterization modified gravity
2011/9/27
There is a distinct possibility that current and future cosmological data can be used to constrain Einstein's theory of gravity on the very largest scales. To be able to do this in a model-independent...
Modified F(R) Horava-Lifshitz gravity: a way to accelerating FRW cosmology
Horava-Lifshitz gravity FRW cosmology
2010/3/19
Masud Chaichian, Shin'ichi Nojiri, Sergei D. Odintsov, Markku Oksanen, Anca Tureanu
(Submitted on 22 Jan 2010 (v1), last revised 14 Mar 2010 (this version, v2))
Abstract: We propose a general approa...
Quantum field theory, gravity and cosmology in a fractal universe
Fractal spacetime Models of Quantum Gravity Cosmology of Theories beyond the SM
2010/3/18
We propose a model for a power-counting renormalizable field theory living in a fractal spacetime. The action is Lorentz covariant and equipped with a Stieltjes measure. The system flows, even in a cl...
A recent study of the satellite galaxies surrounding the Milky Way casts doubt on existing models of dark matter — according to its authors in Germany, Austria and Australia. The locations of the gala...
Modeling Repulsive Gravity with Creation
Cosmology theory observation creation negative energy fields SNe Ia
2009/5/12
There is a growing interest among cosmologists for theories
with negative energy scalar fields and creation, in order to model a repulsive
gravity. The classical steady state cosmology proposed by B...
Modeling Repulsive Gravity with Creation
Cosmology theory observation creation negative energy fields SNe Ia
2010/9/16
There is a growing interest among cosmologists for theories with negative energy scalar fields and creation, in order to model a repulsive gravity. The classical steady state cosmology proposed by Bon...