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Related papers: Probing the Inflaton Potential with SKA

200 papers

We obtain the effective inflaton potential during slow roll inflation by including the one loop quantum corrections to the energy momentum tensor from scalar curvature and tensor perturbations as well as quantum fluctuations from light…

Astrophysics · Physics 2009-11-13 D. Boyanovsky , H. J. de Vega , N. G. Sanchez

The substantial decrease in star formation density from z=1 to the present day is curious given the relatively constant neutral gas density over the same epoch. Future radio astronomy facilities, including the SKA and pathfinder telescopes,…

Astrophysics of Galaxies · Physics 2016-07-27 Natasha Maddox , Matt J. Jarvis , Tom Oosterloo

Non-analyticity in co-moving momenta within the non-Gaussian bispectrum is a distinctive sign of on-shell particle production during inflation, presenting a unique opportunity for the "direct detection" of particles with masses as large as…

High Energy Physics - Phenomenology · Physics 2021-02-23 Arushi Bodas , Soubhik Kumar , Raman Sundrum

We present a method for calculating large numbers of power spectra C_l and P(k) that accelerates CMBfast by a factor around 10^3 without appreciable loss of accuracy, then apply it to constrain 11 cosmological parameters from current Cosmic…

Astrophysics · Physics 2009-10-07 Max Tegmark , Matias Zaldarriaga , Andrew J. S. Hamilton

We consider the renormalization group improvement in the theory of the Standard Model (SM) Higgs boson playing the role of an inflaton with a strong non-minimal coupling to gravity. At the one-loop level with the running of constants taken…

High Energy Physics - Phenomenology · Physics 2012-11-30 A. O. Barvinsky , A. Yu. Kamenshchik , C. Kiefer , A. A. Starobinsky , C. F. Steinwachs

One of the five key science projects for the Square Kilometre Array (SKA) is "The Origin and Evolution of Cosmic Magnetism", in which radio polarimetry will be used to reveal what cosmic magnets look like and what role they have played in…

Instrumentation and Methods for Astrophysics · Physics 2009-11-13 Bryan M. Gaensler

We calculate temperature anisotropies of the cosmic microwave background (CMB) for several initial power spectra of density perturbations with a built-in scale suggested by recent optical data on the spatial distribution of rich clusters of…

Astrophysics · Physics 2009-10-30 F. Atrio-Barandela , J. Einasto , S. Gottlöber , V. Müller , A. A. Starobinsky

High-number-density tracers of large-scale structure, such as the HI-rich galaxies measured by 21 cm intensity mapping, have low sampling noise, making them particularly promising as cosmological probes. At large scales, this sampling noise…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-28 Simon Foreman , Andrej Obuljen , Marko Simonović

We are in the era of precision cosmology which offers us a unique opportunity to investigate beyond standard model physics. Toward this endeavor, inflaton is assumed to be a perfect new physics candidate. In this submission, we explore the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-20 Ayan Chakraborty , Md Riajul Haque , Debaprasad Maity , Rajesh Mondal

This document was submitted as supporting material to an Engineering Change Proposal (ECP) for the Square Kilometre Array (SKA). This ECP requests gridded visibilities as an extra imaging data product from the SKA, in order to enable…

Instrumentation and Methods for Astrophysics · Physics 2015-07-24 Ian Harrison , Michael L. Brown

The cosmological case for a next generation radio observatory, the Square Kilometer Array, is discussed and reviewed. An instrument like the SKA would be able to measure galaxy redshifts of normal late-type galaxies, via the 21 cm line of…

Astrophysics · Physics 2007-05-23 Rien van de Weygaert , Tjeerd S. van Albada

Upcoming large redshift surveys potentially allow precision measurements of the galaxy power spectrum. To accurately measure P(k) on the largest scales, comparable to the depth of the survey, it is crucial that finite volume effects are…

Astrophysics · Physics 2016-01-27 Max Tegmark

The SKA telescopes will bring unparalleled sensitivity across a broad radio band, a wide field of view across the Southern sky, and the capacity for sub-arraying, all of which make them the ideal instruments for studying the pulsar…

The Square Kilometre Array (SKA) will conduct the biggest spectroscopic galaxy survey ever, by detecting the 21cm emission line of neutral hydrogen (HI) from around a billion galaxies over 3/4 of the sky, out to a redshift of z~2. This will…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-08 S. Yahya , P. Bull , M. G. Santos , M. Silva , R. Maartens , P. Okouma , B. Bassett

An algorithm is used to generate new solutions of the scalar field equations in homogeneous and isotropic universes. Solutions can be found for pure scalar fields with various potentials in the absence and presence of spatial curvature and…

General Relativity and Quantum Cosmology · Physics 2016-11-23 John D. Barrow , Andronikos Paliathanasis

Both Phase 1 of the Square Kilometre Array (SKA1) and the full SKA have the potential to dramatically increase the science return from future astrophysics, heliophysics, and especially planetary missions, primarily due to the greater…

Instrumentation and Methods for Astrophysics · Physics 2014-12-19 Dayton L. Jones , Joseph Lazio

We investigate inflation in modified gravity framework by introducing a direct coupling term between a scalar field $\phi$ and the trace of the energy momentum tensor $T$ as $f(\phi,T) = 2 \phi( \kappa^{1/2} \alpha T + \kappa^{5/2} \beta…

General Relativity and Quantum Cosmology · Physics 2022-10-17 Ashmita , Payel Sarkar , Prasanta Kumar Das

We perform null tests of the concordance model, using $H(z)$ measurements that mimic next-generation surveys such as Euclid and the SKA. To this end, we deploy a non-parametric method, so that we make minimal assumptions about the fiducial…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-10 Carlos A. P. Bengaly , Chris Clarkson , Martin Kunz , Roy Maartens

A new method for predicting inflationary cosmological perturbations, based on the Wentzel-Kramers-Brillouin (WKB) approximation, is presented. A general expression for the WKB scalar and tensor power spectra is derived. The main advantage…

Astrophysics · Physics 2009-11-07 Jerome Martin , Dominik J. Schwarz

We forecast the constraints on both Hu-Sawicki model and Bertschinger-Zukin model of modified gravity within the Parameterized Post-Friedmann (PPF) formalism for the Planck satellite experiment by performing the joint analysis of…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-09 Bin Hu , Michele Liguori , Nicola Bartolo , Sabino Matarrese