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相关论文: Constraints on the Cosmic Equation of State using …

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Recent observational indications of an accelerating universe enhance the interest in studying models with a cosmological constant. We investigate cosmological expansion (FRW metric) with $\Lambda>0$ for a general linear equation of state…

广义相对论与量子宇宙学 · 物理学 2016-08-31 A. S. Silbergleit

We conduct the cosmological analysis by using the lens-redshift distribution test with updated galaxy-scale strong lensing sample, where the considered scenarios involve three typical cosmological models (i.e., $\Lambda$CDM, $\omega$CDM and…

宇宙学与河外天体物理 · 物理学 2023-05-01 Hui Li , Yun Chen

Gravitational lensing can provide pure geometric tests of the structure of space-time, for instance by determining empirically the angular diameter distance-redshift relation. This geometric test has been demonstrated several times using…

Spectroscopic surveys such as the Dark Energy Spectroscopic Instrument (DESI) and Euclid are mapping the spatial distribution of millions of galaxies, with Emission Line Galaxies (ELGs) serving as the dominant tracer in the redshift range…

Most gravitational lens systems consist of two or four observable images. The absence of detectable odd images allows us to place a lower limit on the power-law slope of the inner mass profile of lensing galaxies. Using a sample of six…

天体物理学 · 物理学 2009-10-31 D. Rusin , Chung-Pei Ma

Many ambitious experiments have been proposed to constrain dark energy and detect its evolution. At present, observational constraints are consistent with a cosmological constant and there is no firm evidence for any evolution in the dark…

天体物理学 · 物理学 2009-02-26 Sirichai Chongchitnan , George Efstathiou

We review theoretical approaches to the study of galaxy formation, with emphasis on the role of hydrodynamic simulations in modeling the high redshift galaxy population. We present new predictions for the abundance of star-forming galaxies…

天体物理学 · 物理学 2007-05-23 David H. Weinberg , Romeel Dave' , Jeffrey P. Gardner , Lars Hernquist , Neal Katz

In a flat, k=0 cosmology with galaxies that approximate singular isothermal spheres, gravitational lens image separations should be uncorrelated with source redshift. But in an open k=-1 cosmology such gravitational lens image separations…

天体物理学 · 物理学 2009-10-30 Myeong-Gu Park , J. Richard Gott

In this paper we study the cosmic acceleration for five dynamical dark energy models whose equation of state varies with redshift. The cosmological parameters of these models are constrained by performing a MCMC analysis using mainly gas…

宇宙学与河外天体物理 · 物理学 2017-05-31 Juan Magana , V. Motta , Victor H. Cardenas , G. Foex

We study cosmological evolution in a flat FLRW spacetime in the context of modified STEGR gravity or $f(Q)$, using an exponential two-parameter model which represents a smooth perturbative expansion around the $\Lambda$CDM model. The…

广义相对论与量子宇宙学 · 物理学 2025-04-15 Ivan R. Vasquez , A. Oliveros

We explore the properties of dark energy models for which the equation-of-state, w, defined as the ratio of pressure to energy density, crosses the cosmological-constant boundary w = -1. We adopt an empirical approach, treating the dark…

天体物理学 · 物理学 2010-04-06 Robert R. Caldwell , Michael Doran

We present constraints on the equation of state of dark energy, $w$, and the total matter density, $\Omega_{\mathrm{M}}$, derived from the double-source-plane strong lens SDSSJ0946+1006, the first cosmological measurement with a…

宇宙学与河外天体物理 · 物理学 2014-09-15 Thomas E. Collett , Matthew W. Auger

For known gravitational lens systems the redshift distribution of the lenses is compared with theoretical expectations for $10^{4}$~Friedmann-Lema\^\i tre~cosmological models, which more than cover the range of possible cases. The…

天体物理学 · 物理学 2011-05-23 Phillip Helbig , Rainer Kayser

The standard model of cosmology, {\Lambda}CDM, is the simplest model that matches the current observations, but it relies on two hypothetical components, to wit, dark matter and dark energy. Future galaxy surveys and cosmic microwave…

宇宙学与河外天体物理 · 物理学 2018-08-13 Cyrille Doux , Mariana Penna-Lima , Sandro D. P. Vitenti , Julien Tréguer , Eric Aubourg , Ken Ganga

In this work, by using strong gravitational lensing (SGL) observations along with Type Ia Supernovae (Union2.1) and gamma ray burst data (GRBs), we propose a new method to study a possible redshift evolution of $\gamma(z)$, the mass density…

广义相对论与量子宇宙学 · 物理学 2017-08-16 R. F. L. Holanda , S. H. Pereira , Deepak Jain

We use recent measurements of the expansion history of the universe to place constraints on the parameter space of cubic Galileon models, in particular we concentrate on those models which contain the simplest Galileon term plus a linear…

宇宙学与河外天体物理 · 物理学 2013-11-20 Emilio Bellini , Raul Jimenez

The subject of this paper is to investigate the weak regime covariant scalar-tensor-vector gravity (STVG) theory, known as the MOdified gravity (MOG) theory of gravity. First, we show that the MOG in the absence of scalar fields is…

广义相对论与量子宇宙学 · 物理学 2018-10-09 M. Khurshudyan , N. S. Mazhari , D. Momeni , R. Myrzakulov , M. Raza

Recent observational indications of an accelerating universe enhance the interest in studying models with a cosmological constant. We investigate cosmological expansion (FRW metric) with $\Lambda>0$ for a general linear equation of state…

天体物理学 · 物理学 2009-11-07 A. S. Silbergleit

We consider the extent to which future imaging surveys of galaxies can distinguish between dark energy and modified gravity models for the origin of the cosmic acceleration. Dynamical dark energy models may have similar expansion rates as…

天体物理学 · 物理学 2014-11-18 Kazuhiro Yamamoto , David Parkinson , Takashi Hamana , Robert C. Nichol , Yasushi Suto

Applying the distance sum rule in strong gravitational lensing (SGL) and type Ia supernova (SN Ia) observations, one can provide an interesting cosmological model-independent method to determine the cosmic curvature parameter $\Omega_k$. In…

宇宙学与河外天体物理 · 物理学 2020-07-31 Bo Wang , Jing-Zhao Qi , Jing-Fei Zhang , Xin Zhang
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