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Related papers: Dark energy effects on the Lyman-alpha forest

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We outline a dynamical dark energy scenario whose signatures may be simultaneously tested by astronomical observations and laboratory experiments. The dark energy is a field with slightly sub-gravitational couplings to matter, a logarithmic…

Astrophysics · Physics 2009-06-23 Nemanja Kaloper

In this study, we will look at an interacting dark energy model. In the framework of Friedmann-Robertson-Walker (FRW) space-time, we have made the hypothesis of an interacting scheme between two fields (dark matter (DM) and dark energy…

General Relativity and Quantum Cosmology · Physics 2023-11-27 J. K. Singh , Ritika Nagpal

We explore the bounds that can be placed on interactions between cold dark matter and vacuum energy, with equation of state $w=-1$, using state-of-the-art cosmological observations. We consider linear perturbations about a simple background…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Chakkrit Kaeonikhom , Hooshyar Assadullahi , Jascha Schewtschenko , David Wands

So far large and different data sets revealed the accelerated expansion rate of the Universe, which is usually explained in terms of dark energy. The nature of dark energy is not yet known, and several models have been introduced: a non…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-16 M. Demianski , E. Piedipalumbo , D. Sawant , L. Amati

With recent Lyman-alpha forest data from BOSS and XQ-100, some studies suggested that the lower mass limit on the fuzzy dark matter (FDM) particles is lifted up to $10^{-21}\,\mathrm{eV}$. However, such a limit was obtained by $\Lambda$CDM…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-14 Jiajun Zhang , Jui-Lin Kuo , Hantao Liu , Yue-Lin Sming Tsai , Kingman Cheung , Ming-Chung Chu

The integrated Sachs-Wolfe (ISW) effect is an important implication for dark energy. In this paper, we have calculated the power spectrum of the ISW effect in the time varying vacuum cosmological model, where the model parameter…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-19 Yuting Wang , Yuan-Xing Gui , Lixin Xu , Jianbo Lu

(abridged) We present an effective implementation of analytical calculations of the Lyalpha opacity distribution of the Intergalactic Medium (IGM) along multiple lines of sight (LOS) to distant quasars in a cosmological setting. This method…

Astrophysics · Physics 2009-11-06 M. Viel , S. Matarrese , H. J. Mo , M. G. Haehnelt , Tom Theuns

We show that simple models of scalar-field dark energy leave a generic enhancement in the weak-lensing power spectrum when compared to the LCDM prediction. In particular, we calculate the linear-scale enhancement in the convergence (or…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-11 Sirichai Chongchitnan , Lindsay King

The properties of the Lyman-$\alpha$ absorptions observed in the spectra of QSOs are reviewed: the distribution of column densities and Doppler widths, the redshift evolution, the ``inverse effect'', the clustering. By interpreting the…

Astrophysics · Physics 2007-05-23 S. Cristiani

Whilst the underlying assumption of the Friedman-Lema\^itre-Robertson-Walker (FLRW) cosmological model is that matter is homogeneously distributed throughout the universe, gravitational influences over the life of the universe have resulted…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-15 Sonia Akter Ema , Md Rasel Hossen , Krzysztof Bolejko , Geraint F. Lewis

We outline the physical picture of the high-redshift Ly-alpha forest that has emerged from cosmological simulations, describe statistical characteristics of the forest that can be used to test theories of structure formation, present a…

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…

Astrophysics · Physics 2010-04-06 Robert R. Caldwell , Michael Doran

In this paper, we propose a new pressure parametric model of the total cosmos energy components in a spatially flat Friedmann-Robertson-Walker (FRW) universe and then reconstruct the model into quintessence and phantom scenarios,…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-14 Jun-Chao Wang , Xin-He Meng

Assuming that the Universe at higher redshifts (z \sim 4 and beyond) is consistent with LCDM model as constrained by the Planck measurements, we reanalyze the low redshift cosmological data to reconstruct the Hubble parameter as a function…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-18 Koushik Dutta , Ruchika , Anirban Roy , Anjan A. Sen , M. M. Sheikh-Jabbari

Our universe is observed to be accelerating due to the dominant dark energy with negative pressure. The dark energy equation of state (w) holds a key to understanding the ultimate fate of the universe. The cosmic voids behave like bubbles…

Astrophysics · Physics 2011-02-11 Jounghun Lee , Daeseong Park

Dark Energy is some of the weirdest and most mysterious stuff in the universe that tends to increase the rate of expansion of the universe. Two commonly known forms of dark energy are the cosmological constant, a constant energy density…

General Relativity and Quantum Cosmology · Physics 2010-04-28 Ishwaree P. Neupane , Holly Trowland

Current observational bounds on dark energy depend on assumptions about the curvature of the universe. We present a simple and efficient method for incorporating constraints from CMB anisotropy data, and use it to derive constraints on…

Astrophysics · Physics 2010-04-06 Yun Wang , Pia Mukherjee

We study lens statistics in flat, low-density universes with different equations of state $w=p_Q/\rho_Q$ for the dark energy component. Dark energy modifies the distance-redshift relation and the mass function of dark matter halos leading…

Astrophysics · Physics 2009-11-10 M. Kuhlen , C. R. Keeton , P. Madau

We put forward a pressure-parametric model to study the tiny deviation from cosmological constant(CC) behavior of the dark sector accelerating the expansion of the Universe. Data from cosmic microwave background (CMB) anisotropies, baryonic…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-29 Yan-Hong Yao , Xin-He Meng

To explain the acceleration of the cosmological expansion researchers have considered an unusual form of mass-energy generically called dark energy. Dark energy has a ratio of pressure over mass density which obeys $w=p/\rho <-1/3$. This…

High Energy Physics - Theory · Physics 2008-12-19 Max Chaves , Douglas Singleton
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