English
Related papers

Related papers: Revisiting Cardassian Model and Cosmic Constraint

200 papers

We present constraints on cosmological and star formation parameters based on combining observations of the Wilkinson Microwave Anisotropy Probe (WMAP) and high-redshift quasars from the Sloan Digital Sky Survey (SDSS). We use a…

Astrophysics · Physics 2009-11-07 Weihsueh A. Chiu , Xiaohui Fan , Jeremiah P. Ostriker

We introduce a set of two-parameter models for the dark energy equation of state (EOS) $w(z)$ to investigate time-varying dark energy. The models are classified into two types according to their boundary behaviors at the redshift…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Qing-Jun Zhang , Yue-Liang Wu

Physical limits on the equation-of-state (EoS) parameter of a dark energy component non-minimally coupled with the dark matter field are examined in light of the second law of thermodynamics and the positiveness of entropy. Such constraints…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 J. E. Gonzalez , H. H. B. Silva , R. Silva , J. S. Alcaniz

We combine complementary datasets from Cosmic Microwave Background (CMB) anisotropy measurements, high redshift supernovae (SN-Ia) observations and data from local cluster abundances and galaxy clustering (LSS) to constrain the dark energy…

Astrophysics · Physics 2009-11-07 Rachel Bean , Alessandro Melchiorri

While cold dark matter is widely supported by a range of cosmological observations, it encounters several difficulties at smaller scales. These issues have prompted the investigation of various alternative dark matter candidates, leaving…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Jian-Qi Liu , Yan-Hong Yao , Yan Su , Jia-Wei Wu

We consider the weak lensing effect induced by linear cosmological perturbations on the cosmic microwave background (CMB) polarization anisotropies. We find that the amplitude of the lensing peak in the BB mode power spectrum is a faithful…

Astrophysics · Physics 2009-11-13 Viviana Acquaviva , Carlo Baccigalupi

A generic feature of cosmic quintessence models is the possibility of significant energy density in the scalar field during the radiation dominated epoch. This possibility is even greater if the quintessence field begins in a…

Astrophysics · Physics 2007-05-23 G. J. Mathews , K. Ichiki , T. Kajino , M. Orito , M. Yahiro

A new method to investigate a possible time-dependence of the dark energy equation of state $w$ is proposed. We apply this methodology to two of the most recent data sets of type Ia supernova (Union2 and SDSS) and the baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. M. Barboza , J. S. Alcaniz

We present robust, model-marginalized limits on both the total neutrino mass ($\sum m_\nu$) and abundance ($N_{\rm eff}$) to minimize the role of parameterizations, priors and models when extracting neutrino properties from cosmology. The…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-14 Eleonora di Valentino , Stefano Gariazzo , Olga Mena

The concordance (LambdaCDM) model reproduces the main current cosmological observations assuming the validity of general relativity at all scales and epochs, the presence of cold dark matter, and of a cosmological constant, equivalent to a…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-08 Guido Risaliti , Elisabeta Lusso

We use Monte Carlo techniques to simulate the ability of future large high-redshift galaxy surveys to measure the temporal evolution of the dark energy equation-of-state w(z), using the baryonic acoustic oscillations in the clustering power…

Astrophysics · Physics 2009-11-11 Karl Glazebrook , Chris Blake

Power spectrum estimation and evaluation of associated errors in the presence of incomplete sky coverage; non-homogeneous, correlated instrumental noise; and foreground emission is a problem of central importance for the extraction of…

Astrophysics · Physics 2016-08-30 J. Jewell , S. Levin , C. H. Anderson

The dynamics of expansion and large scale structure formation in the multicomponent Universe with dark energy modeled by the minimally coupled scalar field with generalized linear barotropic equation of state (EoS) are analyzed. It is shown…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-09 B. Novosyadlyj , O. Sergijenko , S. Apunevych , V. Pelykh

A new scheme for testing the nuclear matter (NM) equation of state (EoS) at high densities using constraints from compact star (CS) phenomenology is applied to neutron stars with a core of deconfined quark matter (QM). An acceptable EoS…

Astrophysics · Physics 2007-05-23 H. Grigorian , D. Blaschke , T. Klahn

In this paper, we use the type Ia supernovae data to constrain the holographic dark energy model proposed by Li. We also apply a cosmic age test to this analysis. We consider in this paper a spatially flat Friedmann-Robertson-Walker…

Astrophysics · Physics 2008-11-26 Xin Zhang , Feng-Quan Wu

Determining the mechanism behind the current cosmic acceleration constitutes a major question nowadays in theoretical physics. If the dark energy route is taken, this problem may potentially bring to light new insights not only in Cosmology…

Astrophysics · Physics 2009-07-09 E. M. Barboza , J. S. Alcaniz

We have studied constraints on the equation of state, $w$, and speed of sound, c_s, of the dark energy from a joint analysis of data from the cosmic microwave background, large scale structure and type-Ia supernovae. We find that current…

Astrophysics · Physics 2009-11-10 Steen Hannestad

In recent years, the Lambda Cold Dark Matter (LCDM) model, which has been pivotal in cosmological studies, has faced significant challenges due to emerging observational and theoretical inconsistencies. This paper explores alternative…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-04 Dharmendra Kumar , Ayan Mitra , Shahnawaz A. Adil , Anjan A. Sen

The remarkable progress in cosmic microwave background (CMB) studies over past decade has led to the era of precision cosmology in striking agreement with the $\Lambda$CDM model. However, the lack of power in the CMB temperature…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-09 Asif Iqbal , Jayanti Prasad , Tarun Souradeep , Manzoor A. Malik

We introduce a power-law parameterized quintessence model for the dark energy which accelerate universe at the low redshifts while behaves as an ordinary matter for the early universe. We construct a unique scalar potential for this…

Astrophysics · Physics 2008-11-26 Sohrab Rahvar , M. Sadegh Movahed
‹ Prev 1 8 9 10 Next ›