Gedanken Experiment (Thought Experiment) about Gravo-Electric and Gravo-Magnetic Fields, and the Link to Gravitons and Gravitational Waves in the Early Universe

AbstractBlazar observations point toward the possible presence of magnetic fields over intergalactic scales of the order of up to ∼1 Mpc, with strengths of at least ∼10−16 G. Understanding the origin of these large-scale magnetic fields is a challenge for modern astrophysics. Here we discuss the cosmological scenario, focussing on the following questions: (i) How and when was this magnetic field generated? (ii) How does it evolve during the expansion of the universe? (iii) Are the amplitude and statistical properties of this field such that they can explain the strengths and correlation lengths of observed magnetic fields? We also discuss the possibility of observing primordial turbulence through direct detection of stochastic gravitational waves in the mHz range accessible to LISA.

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Numerical Relativity as a Tool for Studying the Early Universe

Journal of Gravity ◽

10.1155/2014/407197 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 2

Author(s):

David Garrison

Keyword(s):

Dark Matter ◽

Magnetic Fields ◽

Numerical Simulations ◽

Gravitational Waves ◽

Early Universe ◽

Large Scale ◽

Numerical Relativity ◽

Turbulent Plasma ◽

The University ◽

Scalar Perturbations

Numerical simulations are becoming a more effective tool for conducting detailed investigations into the evolution of our universe. In this paper, we show how the framework of numerical relativity can be used for studying cosmological models. The author is working to develop a large-scale simulation of the dynamical processes in the early universe. These take into account interactions of dark matter, scalar perturbations, gravitational waves, magnetic fields, and turbulent plasma. The code described in this report is a GRMHD code based on the Cactus framework and is structured to utilize one of several different differencing methods chosen at run-time. It is being developed and tested on the University of Houston’s Maxwell cluster.

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Gravitational waves: A probe to the physics in the early universe

International Journal of Modern Physics A ◽

10.1142/s0217751x15450050 ◽

2015 ◽

Vol 30 (28n29) ◽

pp. 1545005

Author(s):

Qing-Guo Huang

Keyword(s):

Quantum Theory ◽

Gravitational Waves ◽

Early Universe ◽

Upper Bound ◽

Planck Scale ◽

Big Bang ◽

Planck Data ◽

Inflationary Scenario ◽

Fundamental Scale ◽

The Big Bang

Gravitational waves can escape from the big bang and can be taken as a probe to the physics, in particular the inflation, in the early universe. Planck scale is a fundamental scale for quantum theory of gravity. Requiring the excursion distance of inflaton in the field space during inflation yields an upper bound on the tensor-to-scalar ratio. For example, [Formula: see text] for [Formula: see text]. In the typical inflationary scenario, we predict [Formula: see text] and [Formula: see text] which are consistent with Planck data released in 2015 quite well. Subtracting the contribution of thermal dust measured by Planck, BICEP2 data implies [Formula: see text] which is the tightest bound on the tensor-to-scalar ratio from current experiments.

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DECAY OF MAGNETIC FIELDS IN THE EARLY UNIVERSE

Strong and Electroweak Matter 2002 ◽

10.1142/9789812704498_0066 ◽

2003 ◽

Author(s):

MARK HINDMARSH ◽

M. CHRISTENSSON ◽

A. BRANDENBURG

Keyword(s):

Magnetic Fields ◽

Early Universe

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Generation and Amplification of Magnetic Fields in the Early Universe

Highlights of Astronomy ◽

10.1017/s1539299600014738 ◽

2002 ◽

Vol 12 ◽

pp. 709-711 ◽

Cited By ~ 1

Author(s):

James M. Stone

Keyword(s):

Magnetic Fields ◽

Early Universe ◽

Initial Seed

AbstractA very brief review is given of processes that may be responsible for the generation of initial seed magnetic fields in the early Universe, and that can amplify those fields to the levels observed in galaxies in the current epoch.

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Plasma Damping of Gravitational Waves

Symposium - International Astronomical Union ◽

10.1017/s007418090008774x ◽

1990 ◽

Vol 142 ◽

pp. 62-62

Author(s):

C. Sivaram

Keyword(s):

Neutron Star ◽

Magnetic Fields ◽

Gravitational Waves ◽

Plasma Frequency ◽

Landau Damping ◽

Plasma Medium ◽

Plane Gravitational Waves

The possibility of the damping of plane gravitational waves while propagating in a plasma medium is considered. The gravitational plasma frequency, is for a neutron star medium ~ 103Hz, which is the same as the frequency of the gravitational waves emitted by a collapsing star. So resonant damping of such waves within a collapsing star is probable. Estimates are made for the damping length for dense and dilute plasmas (also in the presence of magnetic fields). Analogies with Landau damping are made. Applications to other astrophysical situations are outlined.

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