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We investigate the chiral phase structure of quark matter with spheroidal momentum-space anisotropy specified by one anisotropy parameter $\xi$ in the 2+1 flavor quark-meson model. We find that the chiral phase diagram and the location of…

High Energy Physics - Phenomenology · Physics 2021-10-08 He-Xia Zhang , Ben-Wei Zhang

A quantum expansion parameter, analogous to the Hubble parameter in cosmology, is defined for a free particle quantum wavefunction. By considering the universe as an initial single Gaussian quantum wavepacket whose mass is that of…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-28 A. D. Ernest

Extracting parameter constraints from cosmological observations requires accurate determination of the covariance matrix for use in the likelihood function. We show here that uncertainties in the elements of the covariance matrix propagate…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-30 Scott Dodelson , Michael D. Schneider

As well as the galaxy number density and peculiar velocity, the galaxy intrinsic alignment can be used to test the cosmic isotropy. We study distinctive impacts of the isotropy breaking on the configuration-space two-point correlation…

Cosmology and Nongalactic Astrophysics · Physics 2023-08-11 Maresuke Shiraishi , Teppei Okumura , Kazuyuki Akitsu

We use anisotropic fluid cosmology to describe the present, dark energy-dominated, universe. Similarly to what has been proposed for galactic dynamics, the anisotropic fluid gives an effective description of baryonic matter, dark energy and…

General Relativity and Quantum Cosmology · Physics 2020-07-15 Mariano Cadoni , Andrea P. Sanna , Matteo Tuveri

This paper presents a complete analysis of the effects of second order gravitational perturbations on Cosmic Microwave Background anisotropies, taking explicitly into account scalar, vector and tensor modes. We also consider the second…

Astrophysics · Physics 2009-10-30 Silvia Mollerach , Sabino Matarrese

In this talk I review how a non-zero cosmological constant $\Lambda$ affects the propagation of gravitational waves and their detection in pulsar timing arrays (PTA). If $\Lambda\neq 0$ it turns out that waves are anharmonic in cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Domenec Espriu

We study cosmological perturbations in the context of an interacting dark energy model, in which the cosmological term decays linearly with the Hubble parameter, with concomitant matter production. A previous joint analysis of the…

Astrophysics · Physics 2008-11-26 H. A. Borges , S. Carneiro , J. C. Fabris , C. Pigozzo

We study the sample variance of the matter power spectrum for the standard Lambda Cold Dark Matter universe. We use a total of 5000 cosmological N-body simulations to study in detail the distribution of best-fit cosmological parameters and…

Persistent homology naturally addresses the multi-scale topological characteristics of the large-scale structure as a distribution of clusters, loops, and voids. We apply this tool to the dark matter halo catalogs from the Quijote…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-31 Jacky H. T. Yip , Matteo Biagetti , Alex Cole , Karthik Viswanathan , Gary Shiu

In this paper, we present an accelerating cosmological model by constraining the free parameters using the cosmological datasets in an extended symmetric teleparallel gravity for the flat and anisotropic space-time. We employ a time…

General Relativity and Quantum Cosmology · Physics 2023-06-27 S. A. Narawade , M. Koussour , B. Mishra

Since the discovery of the accelerated expansion of the universe, it was necessary to introduce a new component of matter distribution called dark energy. The standard cosmological model considers isotropy of the pressure and assumes an…

General Relativity and Quantum Cosmology · Physics 2012-10-25 R. Chan , M. F. A. da Silva , J. F. Villas da Rocha

We investigate the parameter estimation problem in a two-qubit system, in which each qubit is independently interacting with its Markovian environment. We study in detail the sensitivity of the estimation on the decoherence rate $\gamma$…

Quantum Physics · Physics 2014-01-14 Zheng Qiang , Yao Yao , Yong Li

We address estimation of the minimum length arising from gravitational theories. In particular, we provide bounds on precision and assess the use of quantum probes to enhance the estimation performances. At first, we review the concept of…

Quantum Physics · Physics 2020-09-16 Alessandro Candeloro , Cristian Degli Esposti Boschi , Matteo G. A. Paris

Interest rises to exploit the full shape information of the galaxy power spectrum, as well as pushing analyses to smaller non-linear scales. Here I use the halo model to quantify the information content in the tomographic angular power…

Cosmology and Nongalactic Astrophysics · Physics 2022-05-04 Fabien Lacasa

Astroparticle physics and cosmology allow us to scan the universe through multiple messengers. It is the combination of these probes that improves our understanding of the universe, both in its composition and its dynamics. Unlike other…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 K. Louedec

The disagreement between low- and high-redshift measurements of the Hubble parameter is emerging as a serious challenge to the standard model of cosmology. We develop a covariant cosmographic analysis of the Hubble parameter in a general…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-13 Roy Maartens , Jessica Santiago , Chris Clarkson , Basheer Kalbouneh , Christian Marinoni

We show that localisation microscopy of multiple weak, incoherent point sources with possibly different intensities in one spatial dimension is equivalent to estimating the amplitudes of a classical mixture of coherent states of a simple…

Quantum Physics · Physics 2020-02-17 Evangelia Bisketzi , Dominic Branford , Animesh Datta

We modified the CLASS code in order to include relativistic galaxy number counts in spatially curved geometries; we present the formalism and study the effect of relativistic corrections on spatial curvature. The new version of the code is…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Enea Di Dio , Francesco Montanari , Alvise Raccanelli , Ruth Durrer , Marc Kamionkowski , Julien Lesgourgues

We consider a cosmological model in which the two major fluid components of the Universe, dark energy and dark matter, flow with distinct four-velocities. This cosmological configuration is equivalent to a single anisotropic fluid,…

General Relativity and Quantum Cosmology · Physics 2013-07-24 Tiberiu Harko , Francisco S. N. Lobo
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