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We consider a model of boosted dark matter (DM), where a fraction of DM is upscattered to relativistic energies by cosmic ray electrons. Such interactions responsible for boosting the DM also attenuate its flux at the Earth. Considering a…

High Energy Physics - Phenomenology · Physics 2025-01-24 Tim Herbermann , Manfred Lindner , Manibrata Sen

For a broad range of parameter values, braneworld models display a remarkable property which we call cosmic mimicry. Cosmic mimicry is characterized by the fact that, at low redshifts, the Hubble parameter in the braneworld model is…

Astrophysics · Physics 2009-11-11 Varun Sahni , Yuri Shtanov , Alexander Viznyuk

The extended Galileon models possess tracker solutions with de Sitter attractors along which the dark energy equation of state is constant during the matter-dominated epoch, i.e. w_DE = -1-s, where s is a positive constant. Even with this…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-19 Antonio De Felice , Shinji Tsujikawa

The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-22 R. S. Goncalves , J. S. Alcaniz , A. Dev , D. Jain

We present a method to measure the growth of structure and the background geometry of the Universe -- with no a priori assumption about the underlying cosmological model. Using Canada-France-Hawaii Lensing Survey (CFHTLenS) shear data we…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-12 Peter L. Taylor , Thomas D. Kitching , Jason D. McEwen

(abridged) We continue the study of $\Lambda$SFDM cosmologies, which differ from $\Lambda$CDM in that CDM is replaced by scalar field dark matter (SFDM) by calculating the evolution of the background Universe, as well as linear…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-16 Horst Foidl , Tanja Rindler-Daller

No experimental test precludes the possibility that the dark matter experiences forces beyond general relativity -- in fact, a variety of cosmic microwave background observations suggest greater late-time structure than predicted in the…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-02 Marco Costa , Cyril Creque-Sarbinowski , Olivier Simon , Zachary J. Weiner

The cosmic microwave background temperature is a cornerstone astrophysical observable. Its present value is tightly constrained, but its redshift dependence, which can now be determined until redshift $z\sim6.34$, is also an important probe…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-23 L. Gelo , C. J. A. P. Martins , N. Quevedo , A. M. M. Vieira

This is the second paper in the series that confronts predictions of a model of the landscape with cosmological observations. We show here how the modifications of the Friedmann equation due to the decohering effects of long wavelength…

High Energy Physics - Theory · Physics 2008-11-26 R. Holman , Laura Mersini-Houghton , Tomo Takahashi

We study the non-linear spherical "top hat" collapse for Chaplygin and viscous unified cosmologies. The term unified refers to models where dark energy and dark matter are replaced by one single component. For the generalized Chaplygin gas…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Thiago R. P. Caramês , Júlio C. Fabris , Hermano E. S. Velten

It has been recently shown that cosmological models with scale-dependent primordial non-Gaussianities (sPNG) could provide a possible path to solve current cosmic tensions. Moreover, it has been pointed out that some of these models might…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-08 Clément Stahl , Benoit Famaey , Rodrigo Ibata , Katarina Kraljic , Fabien Castillo

The Cosmic microwave background (CMB) anisotropies predicted by two cosmological models are compared, one of them is the standard model of general relativity with cold dark matter and cosmological constant, whereas the second model is based…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-19 Roberto Dale , Diego Sáez

We demonstrate that elastic scattering between dark matter (DM) and baryons can affect the thermal evolution of the intergalactic medium at early epochs and discuss the observational consequences. We show that, due to the interaction…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Hiroyuki Tashiro , Kenji Kadota , Joseph Silk

Inspired by a new compilation of strong lensing systems, which consist of 204 points in the redshift range $0.0625< z_{l} < 0.958$ for the lens and $0.196< z_{s} < 3.595$ for the source, we constrain three models that generate a late cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Mario H. Amante , Juan Magaña , V. Motta , Miguel A. García-Aspeitia , Tomás Verdugo

In the present work we have searched the existence of the late time acceleration of the Universe. The matter source that is responsible for the late time acceleration of the Universe consists of cosmic fluid with the equation of state…

General Physics · Physics 2013-01-29 Anil Kumar Yadav , Farook Rahaman , Saibal Ray , G. K. Goswami

The narrow width approximation is used in high energy physics to reduce the complexity of scattering calculations. It is a fortunate accident that it works so well for the Standard Model, but in general it will fail in the context of new…

High Energy Physics - Phenomenology · Physics 2011-01-28 D. Berdine , N. Kauer , D. Rainwater

We study the effects on cosmic microwave background (CMB) temperature and polarization anisotropies of spatial fluctuations of the fine-structure parameter between causally disconnected regions of the Universe at the time of recombination.…

Astrophysics · Physics 2014-10-13 Kris Sigurdson , Andriy Kurylov , Marc Kamionkowski

A full account of galaxy evolution in the context of LCDM cosmology requires measurements of the average star-formation rate (SFR) and cold gas abundance across cosmic time. Emission from the CO ladder traces cold gas, and [CII] fine…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-05 Eric R. Switzer

Interactions between dark matter and dark energy with a given equation of state are known to modify the cosmic dynamics. On the other hand, the strength of these interactions is subject to strong observational constraints. Here we discuss a…

Astrophysics · Physics 2015-05-13 Winfried Zimdahl

In this paper, we investigate cosmological consequences of a scenario for recently reported accelerated expansion of the Universe, in which the generalized Chaplygin gas (GCG) along with the baryonic matter are responsible for this observed…

General Relativity and Quantum Cosmology · Physics 2017-05-24 Hamid Shabani