Cosmology at high redshift — a probe of fundamental physics

Abstract An observational program focused on the high redshift (2<z<6) Universe has the opportunity to dramatically improve over upcoming LSS and CMB surveys on measurements of both the standard cosmological model and its extensions. Using a Fisher matrix formalism that builds upon recent advances in Lagrangian perturbation theory, we forecast constraints for future spectroscopic and 21-cm surveys on the standard cosmological model, curvature, neutrino mass, relativistic species, primordial features, primordial non-Gaussianity, dynamical dark energy, and gravitational slip. We compare these constraints with those achievable by current or near-future surveys such as DESI and Euclid, all under the same forecasting formalism, and compare our formalism with traditional linear methods. Our Python code FishLSS — used to calculate the Fisher information of the full shape power spectrum, CMB lensing, the cross-correlation of CMB lensing with galaxies, and combinations thereof — is publicly available.

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CMB anisotropy science: a review

Proceedings of the International Astronomical Union ◽

10.1017/s1743921312016663 ◽

2012 ◽

Vol 8 (S288) ◽

pp. 42-52 ◽

Cited By ~ 4

Author(s):

Anthony Challinor

Keyword(s):

Dark Matter ◽

Cosmological Model ◽

Cosmic Microwave Background ◽

Gravitational Waves ◽

Early Universe ◽

Critical Role ◽

Microwave Background ◽

Fundamental Physics ◽

Standard Cosmological Model

AbstractThe cosmic microwave background (CMB) provides us with our most direct observational window to the early universe. Observations of the temperature and polarization anisotropies in the CMB have played a critical role in defining the now-standard cosmological model. In this contribution we review some of the basics of CMB science, highlighting the role of observations made with ground-based and balloon-borne Antarctic telescopes. Most of the ingredients of the standard cosmological model are poorly understood in terms of fundamental physics. We discuss how current and future CMB observations can address some of these issues, focusing on two directly relevant for Antarctic programmes: searching for gravitational waves from inflation via B-mode polarization, and mapping dark matter through CMB lensing.

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DYNAMICS OF PERTURBATIONS IN GURZADYAN–XUE COSMOLOGICAL MODELS

International Journal of Modern Physics D ◽

10.1142/s021827180801195x ◽

2008 ◽

Vol 17 (02) ◽

pp. 203-223 ◽

Cited By ~ 1

Author(s):

G. V. VERESHCHAGIN ◽

G. YEGORIAN

Keyword(s):

Perturbation Theory ◽

Cosmological Model ◽

Analytical Solutions ◽

Cosmological Models ◽

Time Varying ◽

Physical Constants ◽

Newtonian Approximation ◽

Standard Cosmological Model

Perturbation theory within Newtonian approximation is presented for cosmological models with time-varying physical constants. Analytical solutions for perturbations dynamics are obtained for each Gurzadyan–Xue model with pressureless matter and radiation. It is found that perturbations grow during the entire expansion within GX models, including the curvature- and vacuum-dominated stage when they cease to grow in the standard cosmological model.

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Selected Topics in Numerical Methods for Cosmology

Universe ◽

10.3390/universe5090192 ◽

2019 ◽

Vol 5 (9) ◽

pp. 192

Author(s):

Sandro Dias Pinto Vitenti ◽

Mariana Penna-Lima

Keyword(s):

Numerical Methods ◽

Cosmological Model ◽

Cosmological Parameters ◽

Systematic Errors ◽

Percent Error ◽

Software Products ◽

Cosmological Data ◽

Standard Cosmological Model ◽

Near Future

The large amount of cosmological data already available (and in the near future) makes the development of efficient numerical codes necessary. Many software products have been implemented to perform cosmological analyses considering one or few probes. The need of multi-task software is rapidly increasing, in order to combine numerous cosmological probes along with their specificity (e.g., astrophysical descriptions and systematic errors). In this work, we mention some of these libraries, bringing out some challenges they will face in the few-percent error era (on the cosmological parameters). We review some concepts of the standard cosmological model, and examine some specific topics on their implementation, bringing, for example, the discussion on how some quantities are numerically defined in different codes. We also consider implementation differences between public codes, mentioning their advantages/disadvantages.

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FUGACITY AND REHEATING OF PRIMORDIAL NEUTRINOS

Modern Physics Letters A ◽

10.1142/s0217732313501885 ◽

2013 ◽

Vol 28 (40) ◽

pp. 1350188 ◽

Cited By ~ 2

Author(s):

JEREMIAH BIRRELL ◽

CHENG-TAO YANG ◽

PISIN CHEN ◽

JOHANN RAFELSKI

Keyword(s):

Cosmological Model ◽

Background Radiation ◽

Chemical Nonequilibrium ◽

Model Parameter ◽

Standard Cosmological Model ◽

Cmb Fluctuations ◽

The Impact ◽

Freeze Out

We clarify in a quantitative way the impact that distinct chemical Tc and kinetic Tk freeze-out temperatures have on the reduction of the neutrino fugacity ϒν below equilibrium, i.e. ϒν<1, and the increase of the neutrino temperature Tν via partial reheating. We establish the connection between ϒν and Tk via the modified reheating relation Tν(ϒν)/Tγ, where Tγ is the temperature of the background radiation. Our results demonstrate that one must introduce the chemical nonequilibrium parameter, i.e. the fugacity, ϒν, as an additional standard cosmological model parameter in the evaluation of CMB fluctuations as its value allows measurement of Tk.

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A CRITIQUE OF THE STANDARD COSMOLOGICAL MODEL : TUTORIAL

Neural Network World ◽

10.14311/nnw.2014.24.026 ◽

2014 ◽

Vol 24 (5) ◽

pp. 435-461 ◽

Cited By ~ 3

Author(s):

Michal Křížek ◽

Lawrence Somer

Keyword(s):

Cosmological Model ◽

Standard Cosmological Model

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O UNIVERSO VIVO

Revista da Universidade Federal de Minas Gerais ◽

10.35699/2316-770x.2012.2718 ◽

2012 ◽

Vol 19 (1.2) ◽

Cited By ~ 7

Author(s):

Francisco César de Sá Barreto ◽

Luiz Paulo Ribeiro Vaz ◽

Gabriel Armando Pellegatti Franco

Keyword(s):

Cosmological Model ◽

Chemical Elements ◽

Big Bang ◽

Living System ◽

Irreversible Processes ◽

Thermodynamics Of Irreversible Processes ◽

Protons And Neutrons ◽

Standard Cosmological Model ◽

The Big Bang ◽

The Universe

The standard cosmological model suggests that after the “Big Bang”, 14 billion of years ago, the universe entered a period of expansion and cooling. In the first one millionth of a second appear quarks, glúons, electrons and neutrinos, followed by the appearance of protons and neutrons. In this paper, we describe the “cosmic battle” between gravitation and energy, responsible for the lighter chemical elements and the formation of the stars. We describe the thermodynamics of irreversible processes of systems which are far away from equilibrium, a route that is followed by the universe, seen as a living system.

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The Perturbation of Material Density in f(R) Modified Gravity of Polynormal Exponential Form

10.29007/xqpk ◽

2020 ◽

Author(s):

Van On Vo

Keyword(s):

Cosmological Model ◽

Modified Gravity ◽

Linear Perturbation ◽

Exponential Form ◽

Material Density ◽

Gravitational Model ◽

Standard Cosmological Model ◽

The Difference ◽

Evolutionary Aspects ◽

The Universe

In this paper, we investigate the linear perturbation of the material density of the universe in f(R) modified gravity of polynomial exponential form on the scale of distance below the cosmic horizon (sub-horizon). The results show that the model for the evolutionary aspects of the universe is slightly different from that in the standard cosmological model of ΛCDM. They can be used to show the difference between this modified gravitational model with the standard cosmological model of ΛCMD and other cosmological models. We also investigate the ration Ψ/ Φ and Geff / GN in the model and show that they are within allowable limits of experiments.

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