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Related papers: Dark energy and cosmic curvature: Monte-Carlo Mark…

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We investigate the dark energy phenomenology in an extended parameter space where we allow the curvature density of our universe as a free-to-vary parameter. The inclusion of the curvature density parameter is motivated from the recently…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-29 Mehdi Rezaei , Supriya Pan , Weiqiang Yang , David F. Mota

We explore the properties of dark energy from recent observational data, including the Gold Sne Ia, the baryonic acoustic oscillation peak from SDSS, the CMB shift parameter from WMAP3, the X-ray gas mass fraction in cluster and the Hubble…

Astrophysics · Physics 2008-11-26 Puxun Wu , Hongwei Yu

We show that the assumption of a flat universe induces critically large errors in reconstructing the dark energy equation of state at z>~0.9 even if the true cosmic curvature is very small, O(1%) or less. The spuriously reconstructed w(z)…

Astrophysics · Physics 2008-11-26 Chris Clarkson , Marina Cortes , Bruce A. Bassett

In this paper, we propose a new parametrization of dark energy based on the $Om(z)$ diagnostic tool behavior. For this purpose, we investigate a functional form of the $Om(z)$ that predicts the popular dark energy dynamical models, namely…

General Relativity and Quantum Cosmology · Physics 2023-07-13 N. Myrzakulov , M. Koussour , Dhruba Jyoti Gogoi

In this paper we review in detail a number of approaches that have been adopted to try and explain the remarkable observation of our accelerating Universe. In particular we discuss the arguments for and recent progress made towards…

High Energy Physics - Theory · Physics 2008-11-26 Edmund J. Copeland , M. Sami , Shinji Tsujikawa

We use the Markov Chain Monte Carlo method to investigate a global constraints on the generalized Chaplygin gas (GCG) model as the unification of dark matter and dark energy from the latest observational data: the Constitution dataset of…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-07 Lixin Xu , Jianbo Lu

The holographic dark energy model is proposed by Li as an attempt for probing the nature of dark energy within the framework of quantum gravity. The main characteristic of holographic dark energy is governed by a numerical parameter $c$ in…

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

We propose to use alternative cosmic tracers to measure the dark energy equation of state and the matter content of the Universe [w(z) & Omega_m]. Our proposed method consists of two components: (a) tracing the Hubble relation using HII…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 M. Plionis , R. Terlevich , S. Basilakos , F. Bresolin , E. Terlevich , J. Melnick , R. Chavez

In this paper, we study the cosmological implications of the 100 square degree Weak Lensing survey (the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys). We combine these weak lensing data with the cosmic microwave background (CMB)…

Astrophysics · Physics 2010-05-07 Hong Li , Jie Liu , Jun-Qing Xia , Lei Sun , Zu-Hui Fan , Charling Tao , Andre Tilquin , Xinmin Zhang

We focus on uncertainties in supernova measurements, in particular of individual magnitudes and redshifts, to review to what extent supernovae measurements of the expansion history of the universe are likely to allow us to constrain a…

Astrophysics · Physics 2011-05-12 Lawrence M. Krauss , Katherine Jones-Smith , Dragan Huterer

Recent cosmological observations suggest that the dark energy equation of state may have changed in the latter stages of cosmic history. We introduce a quintessence scenario, termed bounded dark energy, capable of explaining this feature in…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-18 Giulia Borghetto , Ameek Malhotra , Gianmassimo Tasinato , Ivonne Zavala

In this paper, a holographic dark energy model, dubbed Ricci dark energy, is confronted with cosmological observational data from type Ia supernovae (SN Ia), baryon acoustic oscillations (BAO) and cosmic microwave background (CMB). By using…

Astrophysics · Physics 2014-11-18 Lixin Xu , Wenbo Li , Jianbo Lu , Baorong Chang

Observing dark energy dynamics is the most important aspect of the dark energy research. In this paper we perform an analysis of the constraints on the property of dark energy from the current astronomical observations. We pay particular…

Astrophysics · Physics 2009-11-13 Jun-Qing Xia , Gong-Bo Zhao , Bo Feng , Hong Li , Xinmin Zhang

We present a Bayesian approach to combine $Planck$ data and the X-ray physical properties of the intracluster medium in the virialization region of a sample of 320 galaxy clusters ($0.056<z<1.24$, $kT>3$ keV) observed with $Chandra$. We…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Andrea Morandi , Ming Sun

In this paper, we give a conceptual explanation of dark energy as a small negative residual scalar curvature present even in empty spacetime. This curvature ultimately results from postulating a discrete spacetime geometry, very closely…

Mathematical Physics · Physics 2012-08-16 Aaron Trout

We apply the Union2 compilation of 557 supernova Ia data, the baryon acoustic oscillation measurement of distance, the cosmic microwave background radiation data from the seven year Wilkinson Microwave Anisotropy Probe, and the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-27 Yungui Gong , Xiao-ming Zhu , Zong-Hong Zhu

We investigate deviations from the cosmic distance duality relation adopting model-dependent and -independent approaches using i) a Taylor expansion, ii) a power-law parameterization, iii) a logarithmic correction, iv) a (2;1) Pad\'e…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-05 Anna Chiara Alfano

A new dark energy model called "ghost dark energy" was recently suggested to explain the observed accelerating expansion of the universe. This model originates from the Veneziano ghost of QCD. The dark energy density is proportional to…

High Energy Physics - Theory · Physics 2015-03-19 A. Sheykhi , M. Sadegh Movahed

By using a Markov Chain Monte Carlo simulation, we investigate cosmological constraints on the ghost dark energy (GDE) model in the framework of the Brans-Dicke (BD) theory. A combination of the latest observational data of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-13 Hamzeh Alavirad , Ahmad Sheykhi

Dark energy can be investigated in two complementary ways, by considering either general parameterizations or physically well-defined models. Following the second route, we explore the constraints on quintessence models where the…