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Related papers: The Optimal Cosmic Epoch for Precision Cosmology

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One of the toughest challenges in modern cosmology is to probe the small scales $k \sim 0.5\,$Mpc$^{-1}$ in the matter power spectrum and clustering. We show that such small scales will be accessible via upcoming line-intensity mapping…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-21 Sarah Libanore , Caner Unal , Debanjan Sarkar , Ely D. Kovetz

A higher value of Hubble constant has been obtained from measurements with nearby Type Ia supernovae, than that obtained at much higher redshift. With the peculiar motions of their hosts, we find that the matter content at such low redshift…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-25 Shuang-Nan Zhang , Yin-Zhe Ma

Six challenges for the standard cosmological model $\Lambda$CDM are listed, which arise when comparing theoretical predictions with observational data on scales of ~1 Mpc. Different parameters of luminous and dwarf galaxies in the local…

General Relativity and Quantum Cosmology · Physics 2026-05-29 I. D. Karachentsev

The simplest cosmological model ($\Lambda$CDM) is well-known to suffer from the Hubble tension, namely an almost $5 \sigma$ discrepancy between the (model-based) early-time determination of the Hubble constant $H_0$ and its late-time (and…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-06 Darshan Kumar , Debajyoti Choudhury , Debottam Nandi

The Cosmological Principle states that the universe is both homogeneous and isotropic. This, alone, is not enough to specify the global geometry of the spacetime. If we were able to measure both the Hubble constant and the energy density we…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Edward Malec , Niall Ó Murchadha

Variations in $\Omega$, the total density of the Universe, leave a clear and distinctive imprint on the power spectrum of temperature fluctuations in the cosmic microwave background (CMB). This signature is virtually independent of other…

Astrophysics · Physics 2009-10-28 Gerard Jungman , Marc Kamionkowski , Arthur Kosowsky , David N. Spergel

The cosmic microwave background anisotropy is sensitive to the slope and amplitude of primordial energy density and gravitational wave fluctuations, the baryon density, the Hubble constant, the cosmological constant, the ionization history,…

An anthropic understanding of the cosmological constant requires that the vacuum energy at late time scans from one patch of the universe to another. If the vacuum energy during inflation also scans, the various patches of the universe…

High Energy Physics - Theory · Physics 2014-11-18 Brian Feldstein , Lawrence J. Hall , Taizan Watari

It is possible that there may be differences in the fundamental physical parameters from one side of the observed universe to the other. I show that the cosmological constant is likely to be the most sensitive of the physical parameters to…

High Energy Physics - Phenomenology · Physics 2009-11-07 John F. Donoghue

We observationally examine cosmological models based on primordial power spectra with quantized wavevectors. Introducing a linearly quantized power spectrum with $k_0=3.225\times10^{-4}\mathrm{Mpc}^{-1}$ and spacing $\Delta k = 2.257 \times…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-18 D. J. Bartlett , W. J. Handley , A. N. Lasenby

The multipole moments of the power spectrum of large scale structure, observed in redshift space, are calculated for a finite sample volume including the effects of both the linear velocity field and geometry. A variance calculation is also…

Astrophysics · Physics 2009-10-30 Andrew A. de Laix , Glenn Starkman

A unique feature of gravity is its ability to control the information accessible to any specific observer. We quantify the notion of cosmic information ('CosmIn') for an eternal observer in the universe. Demanding the finiteness of CosmIn…

General Relativity and Quantum Cosmology · Physics 2017-08-28 T. Padmanabhan , Hamsa Padmanabhan

The SKA will build upon early detections of the EoR by precursor instruments, such as MWA, PAPER, and LOFAR, and planned instruments, such as HERA, to make the first high signal-to-noise measurements of fluctuations in the 21 cm brightness…

We forecast the ability of future CMB and galaxy lensing surveys to constrain variations of the fine structure constant. We found that lensing data, as those expected from satellite experiments as Euclid could improve the constraint from…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Matteo Martinelli , Eloisa Menegoni , Alessandro Melchiorri

A significant tension has become manifest between the current expansion rate of our Universe measured from the cosmic microwave background by the Planck satellite and from local distance probes, which has prompted for interpretations of…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-27 Lucas Lombriser

The cosmological principle states that the Universe is statistically homogeneous and isotropic at large distance scales. There currently exist many observations which indicate a departure from this principle. It has been shown that many of…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-31 Shamik Ghosh , Pankaj Jain , Rahul Kothari , Mohit Panwar , Gurmeet Singh , Prabhakar Tiwari

Cosmology has entered an era of unprecedented precision, yet increasing accuracy has revealed cracks in the standard $\Lambda$CDM paradigm. Although the model remains highly successful when confronted with individual datasets, joint…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-06 Eleonora Di Valentino

We constrain cosmological parameters using only Hubble parameter data and quantify the impact of future Hubble parameter measurements on parameter estimation for the most typical dark energy models. We first constrain cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-27 Jia-Jia Geng , Rui-Yun Guo , Anzhong Wang , Jing-Fei Zhang , Xin Zhang

Many extensions of the Standard Model predict large numbers of additional unstable particles whose decays in the early universe are tightly constrained by observational data. For example, the decays of such particles can alter the ratios of…

High Energy Physics - Phenomenology · Physics 2019-02-20 Keith R. Dienes , Jason Kumar , Patrick Stengel , Brooks Thomas

The onset of stochasticity is measured in $\Lambda$CDM cosmological simulations using a set of classical observables. It is quantified as the local derivative of the logarithm of the dispersion of a given observable (within a set of…

Astrophysics · Physics 2009-11-13 Jerome Thiebaut , Christophe Pichon , Thierry Sousbie , Simon Prunet , D. Pogosyan