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We present new cosmological constraints in a set of motivated extensions of the $\Lambda$CDM model using the polarization and gravitational lensing measurements from the South Pole Telescope and the Planck CMB temperature observations at…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-14 Anton Chudaykin , Dmitry Gorbunov , Nikita Nedelko

In this work, we investigate Big Bang Nucleosynthesis (BBN) within the framework of $f(T,{L}_m)$ gravity, where the gravitational Lagrangian is generalized as a function of the torsion scalar $T$ and the matter Lagrangian ${L}_m$. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-25 Daniel F. P. Cruz , David S. Pereira , Francisco S. N. Lobo , José P. Mimoso

There are many indications that ordinary matter represents only a tiny fraction of the matter content of the Universe, with the remainder assumed to consist of some different type of matter, which, for various reasons must be nonluminous…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Marcelo Salgado , Daniel Sudarsky , Hernando Quevedo

We examine constraints from Big Bang nucleosynthesis on type II Randall-Sundrum brane cosmologies with both a dark radiation component and a quadratic term that depends on the 5-dimensional Planck mass, M_5. Using limits on the abundances…

Astrophysics · Physics 2009-11-07 Jonathan D. Bratt , A. C. Gault , Robert J. Scherrer , T. P. Walker

Using several cosmological observations, i.e. the cosmic microwave background anisotropies (WMAP), the weak gravitational lensing (CFHTLS), the measurements of baryon acoustic oscillations (SDSS+WiggleZ), the most recent observational…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-07 Xin Wang , Xiao-Lei Meng , Tong-Jie Zhang , HuanYuan Shan , Yan Gong , Charling Tao , Xuelei Chen , Y. F. Huang

This conference proceedings paper provides a short summary of the constraints presented by Menci et al. (2020) and Menci et al. (2022) to dynamical dark energy models. Dynamical dark energy (DDE) models have been proposed to address several…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Paola Santini , Nicola Menci , Marco Castellano

We present observational constraints on large-scale white noise (LSWN) in the cosmic density field, a phenomenon predicted to arise from non-linear mode coupling during cosmological evolution. Building on the theoretical framework of Paper…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-21 Gabriela Barenboim , Aurora Ireland , Albert Stebbins

We have performed a thorough analysis of the constraints which can be put on neutrino parameters from cosmological observations, most notably those from the WMAP satellite and the 2dF galaxy survey. For this data we find an upper limit on…

Astrophysics · Physics 2009-11-07 Steen Hannestad

We investigate the observational constraints on the inhomogeneous big-bang nucleosynthesis that Matsuura et al. suggested the possibility of the heavy element production beyond ${}^7$Li in the early universe. From the observational…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-21 Riou Nakamura , Masa-aki Mashimoto , Shin-ichiro Fujimoto , Katsuhiko Sato

Any theory invoked to explain cosmic acceleration predicts consistency relations between the expansion history, structure growth, and all related observables. Currently there exist high-quality measurements of the expansion history from…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 R. Ali Vanderveld , Michael J. Mortonson , Wayne Hu , Tim Eifler

Using an approximate solution to the $N$-body problem in general relativity, and the \emph{principle of local isotropy at any point}, we construct a cosmological model, with zero curvature, for a universe composed uniquely by collision-less…

General Relativity and Quantum Cosmology · Physics 2014-09-11 Miguel Portilla

Big Bang Nucleosynthesis can provide, via constraints on the expansion rate at that time, limits on possible variations in Newton's Constant, $G$. The original analyses were performed before an independent measurement of the…

Astrophysics · Physics 2009-11-10 Craig J. Copi , Adam N. Davis , Lawrence M. Krauss

We present results from the analysis of cosmic microwave background (CMB), large scale structure (galaxy redshift survey) and X-ray galaxy cluster (baryon fraction and X-ray luminosity function) data, assuming a geometrically flat…

Astrophysics · Physics 2009-11-10 S. W. Allen , R. W. Schmidt , S. L. Bridle

The self-gravitating gas in the Newtonian limit is studied in the presence of dark energy with a linear and constant equation of state. Entropy extremization associates to the isothermal Boltzmann distribution an effective density that…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-15 Zacharias Roupas , Minos Axenides , George Georgiou , Emmanuel N. Saridakis

We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Erminia Calabrese , Eloisa Menegoni , C. J. A. P. Martins , Alessandro Melchiorri , Graca Rocha

The term dark radiation is used both to describe a noninteracting neutrino species and as a correction to the Friedmann Equation in the simplest five-dimensional RS-II brane-world cosmology. In this paper we consider the constraints on both…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-04 Nishanth Sasankan , Mayukh. R. Gangopadhyay , Grant. J. Mathews , Motohiko Kusakabe

In this work we perform some studies related to dark energy. Firstly, we propose a dynamical approach to explain the dark energy content of the universe. We assume that a massless scalar field couples to the Hubble parameter with some…

High Energy Physics - Phenomenology · Physics 2009-01-07 Fei Wang , Jin Min Yang

The inability of primordial baryonic density fluctuations, as observed in the cosmic microwave background (CMB), to grow into the present day astronomical structures is well established, under Newtonian and Einsteinian gravity. It is hence…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-03 X. Hernandez , M. A. Jimenez

Scalar dark matter can interact with Standard Model (SM) particles, altering the fundamental constants of Nature in the process. Changes in the fundamental constants during and prior to Big Bang nucleosynthesis (BBN) produce changes in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-14 Y. V. Stadnik , V. V. Flambaum

We consider cosmic chronometer (CC) data for the Hubble parameter, quasar (QSO) luminosities data of X-rays and ultraviolet rays emission, and the latest measurements of the present value of the Hubble parameter from 2018 Planck mission…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Bikash R. Dinda , Haveesh Singirikonda , Subhabrata Majumdar