The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Mubasher Jamil - One of the best experts on this subject based on the ideXlab platform.
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power law entropy corrected holographic Dark Energy model
General Relativity and Gravitation, 2011Co-Authors: A Sheykhi, Mubasher JamilAbstract:Among various scenarios to explain the acceleration of the universe expansion, the holographic Dark Energy (HDE) model has got a lot of enthusiasm recently. In the derivation of holographic Energy density, the area relation of the black hole entropy plays a crucial role. Indeed, the power-law corrections to entropy appear in dealing with the entanglement of quantum fields in and out the horizon. Inspired by the power-law corrected entropy, we propose the so-called “power-law entropy-corrected holographic Dark Energy” (PLECHDE) in this Letter. We investigate the cosmological implications of this model and calculate some relevant cosmological parameters and their evolution. We also briefly study the so-called “power-law entropy-corrected agegraphic Dark Energy” (PLECADE).
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erratum holographic Dark Energy with varying gravitational constant in hořava lifshitz cosmology
Journal of Cosmology and Astroparticle Physics, 2010Co-Authors: M R Setare, Mubasher JamilAbstract:We investigate the holographic Dark Energy scenario with a varying gravitational constant in a flat background in the context of Hořava-Lifshitz gravity. We extract the exact differential equation determining the evolution of the Dark Energy density parameter, which includes G variation term. Also we discuss a cosmological implication of our work by evaluating the Dark Energy equation of state for low redshifts containing varying G corrections.
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holographic Dark Energy with varying gravitational constant
Physics Letters B, 2009Co-Authors: Mubasher Jamil, Emmanuel N Saridakis, M R SetareAbstract:We investigate the holographic Dark Energy scenario with a varying gravitational constant, in flat and non-flat background geometry. We extract the exact differential equations determining the evolution of the Dark Energy density-parameter, which include G-variation correction terms. Performing a low-redshift expansion of the Dark Energy equation of state, we provide the involved parameters as functions of the current density parameters, of the holographic Dark Energy constant and of the G-variation.
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interacting Dark Energy with inhomogeneous equation of state
European Physical Journal C, 2008Co-Authors: Mubasher Jamil, Muneer Ahmad RashidAbstract:We have investigated the model of Dark Energy interacting with Dark matter by choosing inhomogeneous equations of state for the Dark Energy and a nonlinear interaction term for the underlying interaction. The equations of state have dependencies either on the Energy densities, the redshift, the Hubble parameter or the bulk viscosity. We have considered these possibilities and have derived the effective equations of state for the Dark Energy in each case.
D. Yvon - One of the best experts on this subject based on the ideXlab platform.
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prospects for Dark Energy evolution a frequentist multi probe approach
Astronomy and Astrophysics, 2006Co-Authors: C. Yeche, A. Ealet, A. Refregier, C. Tao, A. Tilquin, J.-m. Virey, D. YvonAbstract:A major quest in cosmology is to understand the nature of Dark Energy. It is now well known that the use of several cosmological probes is required to break the underlying degeneracies on cosmological parameters. In this paper, we present a method based on a frequentist approach that combines probes without any prior constraints. As one application, the current supernovae type Ia and cosmic microwave background data are analyzed with an evolving Dark Energy component, and our results are first compared to other analyses. We emphasize the consequences of implementing the Dark Energy perturbations for an equation of state that varies with time. We then simulate the expectations of different future projects. The constraints from weak lensing surveys on the measurement of Dark Energy evolution are combined with the measurements from the cosmic microwave background and type Ia supernovae. We present the impacts for mid-term and long-term surveys and confirm that the combination with weak lensing is very powerful in breaking parameter degeneracies. A second generation of experiments is, however, required to achieve a 0.1 error on the parameters describing the evolution of Dark Energy.
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Prospects for Dark Energy Evolution: a Frequentist Multi-Probe Approach
The Astrophysical Journal, 2005Co-Authors: C. Yeche, A. Ealet, A. Refregier, C. Tao, A. Tilquin, J.-m. Virey, D. YvonAbstract:A major quest in cosmology is the understanding of the nature of Dark Energy. It is now well known that a combination of cosmological probes is required to break the underlying degeneracies on cosmological parameters. In this paper, we present a method, based on a frequentist approach, to combine probes without any prior constraints, taking full account of the correlations in the parameters. As an application, a combination of current SNIa and CMB data with an evolving Dark Energy component is first compared to other analyses. We emphasise the consequences of the implementation of the Dark Energy perturbations on the result for a time varying equation of state. The impact of future weak lensing surveys on the measurement of Dark Energy evolution is then studied in combination with future measurements of the cosmic microwave background and type Ia supernovae. We present the combined results for future mid-term and long-term surveys and confirm that the combination with weak lensing is very powerful in breaking parameter degeneracies. A second generation of experiment is however required to achieve a 0.1 error on the parameters describing the evolution of Dark Energy.
M R Setare - One of the best experts on this subject based on the ideXlab platform.
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erratum holographic Dark Energy with varying gravitational constant in hořava lifshitz cosmology
Journal of Cosmology and Astroparticle Physics, 2010Co-Authors: M R Setare, Mubasher JamilAbstract:We investigate the holographic Dark Energy scenario with a varying gravitational constant in a flat background in the context of Hořava-Lifshitz gravity. We extract the exact differential equation determining the evolution of the Dark Energy density parameter, which includes G variation term. Also we discuss a cosmological implication of our work by evaluating the Dark Energy equation of state for low redshifts containing varying G corrections.
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holographic Dark Energy with varying gravitational constant
Physics Letters B, 2009Co-Authors: Mubasher Jamil, Emmanuel N Saridakis, M R SetareAbstract:We investigate the holographic Dark Energy scenario with a varying gravitational constant, in flat and non-flat background geometry. We extract the exact differential equations determining the evolution of the Dark Energy density-parameter, which include G-variation correction terms. Performing a low-redshift expansion of the Dark Energy equation of state, we provide the involved parameters as functions of the current density parameters, of the holographic Dark Energy constant and of the G-variation.
Debasish Majumdar - One of the best experts on this subject based on the ideXlab platform.
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addressing the high f problem in pseudo nambu goldstone boson Dark Energy models with Dark matter Dark Energy interaction
European Physical Journal C, 2020Co-Authors: Upala Mukhopadhyay, Avik Paul, Debasish MajumdarAbstract:We consider a Dark Energy scenario driven by a scalar field with a pseudo-Nambu–Goldstone boson (pNGB) type potential . The pNGB originates out of breaking of spontaneous symmetry at a scale f close to Planck mass . We consider two cases namely the quintessence Dark Energy model with pNGB potential and the other, where the standard pNGB action is modified by the terms related to Slotheon cosmology. We demonstrate that for this pNGB potential, high-f problem is better addressed when the interaction between Dark matter and Dark Energy is taken into account and that Slotheon Dark Energy scenario works even better over quintessence in this respect. To this end, a mass limit for Dark matter is also estimated.
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probing pseudo nambu goldstone boson Dark Energy models with Dark matter Dark Energy interaction
arXiv: Cosmology and Nongalactic Astrophysics, 2019Co-Authors: Upala Mukhopadhyay, Avik Paul, Debasish MajumdarAbstract:We consider a Dark Energy scenario driven by a scalar field $\Phi$ with a pseudo Nambu Goldstone boson (pNGB) type potential $V(\phi)=\mu^4 \left( 1+ {\rm cos}(\phi/f) \right)$. The pNGB originates out of breaking of spontaneous symmetry at a scale $f$ close to Planck mass $M_{\rm{pl}}$. We consider two cases namely the quintessence Dark Energy and the other, where the standard pNGB action is modified by the terms related to Slotheon cosmology. We demonstrate that for this pNGB potential, high-$f$ problem is better addressed when interaction between Dark matter and Dark Energy is taken into account and that Slotheon Dark Energy scenario works even better over quintessence in this respect. To this end, a mass limit for Dark matter is also estimated.
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addressing the high f problem in pseudo nambu goldstone boson Dark Energy models with Dark matter Dark Energy interaction
arXiv: Cosmology and Nongalactic Astrophysics, 2019Co-Authors: Upala Mukhopadhyay, Avik Paul, Debasish MajumdarAbstract:We consider a Dark Energy scenario driven by a scalar field $\phi$ with a pseudo Nambu Goldstone boson (pNGB) type potential $V(\phi)=\mu^4 \left( 1+ {\rm cos}(\phi/f) \right)$. The pNGB originates out of breaking of spontaneous symmetry at a scale $f$ close to Planck mass $M_{\rm{pl}}$. We consider two cases namely the quintessence Dark Energy and the other, where the standard pNGB action is modified by the terms related to Slotheon cosmology. We demonstrate that for this pNGB potential, high-$f$ problem is better addressed when interaction between Dark matter and Dark Energy is taken into account and that Slotheon Dark Energy scenario works even better over quintessence in this respect. To this end, a mass limit for Dark matter is also estimated.
C. Yeche - One of the best experts on this subject based on the ideXlab platform.
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prospects for Dark Energy evolution a frequentist multi probe approach
Astronomy and Astrophysics, 2006Co-Authors: C. Yeche, A. Ealet, A. Refregier, C. Tao, A. Tilquin, J.-m. Virey, D. YvonAbstract:A major quest in cosmology is to understand the nature of Dark Energy. It is now well known that the use of several cosmological probes is required to break the underlying degeneracies on cosmological parameters. In this paper, we present a method based on a frequentist approach that combines probes without any prior constraints. As one application, the current supernovae type Ia and cosmic microwave background data are analyzed with an evolving Dark Energy component, and our results are first compared to other analyses. We emphasize the consequences of implementing the Dark Energy perturbations for an equation of state that varies with time. We then simulate the expectations of different future projects. The constraints from weak lensing surveys on the measurement of Dark Energy evolution are combined with the measurements from the cosmic microwave background and type Ia supernovae. We present the impacts for mid-term and long-term surveys and confirm that the combination with weak lensing is very powerful in breaking parameter degeneracies. A second generation of experiments is, however, required to achieve a 0.1 error on the parameters describing the evolution of Dark Energy.
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Prospects for Dark Energy Evolution: a Frequentist Multi-Probe Approach
The Astrophysical Journal, 2005Co-Authors: C. Yeche, A. Ealet, A. Refregier, C. Tao, A. Tilquin, J.-m. Virey, D. YvonAbstract:A major quest in cosmology is the understanding of the nature of Dark Energy. It is now well known that a combination of cosmological probes is required to break the underlying degeneracies on cosmological parameters. In this paper, we present a method, based on a frequentist approach, to combine probes without any prior constraints, taking full account of the correlations in the parameters. As an application, a combination of current SNIa and CMB data with an evolving Dark Energy component is first compared to other analyses. We emphasise the consequences of the implementation of the Dark Energy perturbations on the result for a time varying equation of state. The impact of future weak lensing surveys on the measurement of Dark Energy evolution is then studied in combination with future measurements of the cosmic microwave background and type Ia supernovae. We present the combined results for future mid-term and long-term surveys and confirm that the combination with weak lensing is very powerful in breaking parameter degeneracies. A second generation of experiment is however required to achieve a 0.1 error on the parameters describing the evolution of Dark Energy.
