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4.0

Jun 30, 2018
06/18

by
Ronaldo S. S. Vieira; Włodek Kluźniak; Marek Abramowicz

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The sum of squared epicyclic frequencies of nearly circular motion ($\omega_r^2+\omega_\theta^2$) in axially symmetric configurations of Newtonian gravity is known to depend both on the matter density and on the angular velocity profile of circular orbits. It was recently found that this sum goes to zero at the photon orbits of Schwarzschild and Kerr spacetimes. However, these are the only relativistic configurations for which such result exists in the literature. Here, we extend the above...

Topics: General Relativity and Quantum Cosmology, High Energy Astrophysical Phenomena, Cosmology and...

Source: http://arxiv.org/abs/1701.08873

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2.0

Jun 29, 2018
06/18

by
James Bonifacio; Kurt Hinterbichler; Rachel A. Rosen

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We derive analyticity constraints on a nonlinear ghost-free effective theory of a massive spin-2 particle known as pseudo-linear massive gravity, and on a generalized theory of a massive spin-1 particle, both of which provide simple IR completions of Galileon theories. For pseudo-linear massive gravity we find that, unlike dRGT massive gravity, there is no window of parameter space which satisfies the analyticity constraints. For massive vectors which reduce to Galileons in the decoupling...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1607.06084

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3.0

Jun 29, 2018
06/18

by
Seema Satin; H. T. Cho; Bei Lok Hu

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For a conformally-coupled scalar field we obtain the conformally-related Einstein-Langevin equations, using appropriate transformations for all the quantities in the equations between two conformally-related spacetimes. In particular, we analyze the transformations of the influence action, the stress energy tensor, the noise kernel and the dissipation kernel. In due course the fluctuation-dissipation relation is also discussed. The analysis in this paper thereby facilitates a general solution...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1603.06206

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2.0

Jun 30, 2018
06/18

by
Sushant G. Ghosh; Uma Papnoi; Sunil D. Maharaj

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Lovelock theory is a natural extension of the Einstein theory of general relativity to higher dimensions in which the first and second orders correspond, respectively, to general relativity and Einstein-Gauss-Bonnet gravity. We present exact black hole solutions of $D\geq 4$-dimensional spacetime for first-, second-, and third-order Lovelock gravities in a string cloud background. Further, we compute the mass, temperature, and entropy of black hole solutions for the higher-dimensional general...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1408.4611

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4.0

Jun 30, 2018
06/18

by
Slobodan Prvanovic

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Within the framework of self-adjoint operator of time in non-relativistic quantum mechanics the equation describing change of the state of quantum system with respect to energy is introduced. The operator of time appears to be the generator of the change of energy while the operator of energy, that is conjugate to the operator of time, generates time evolution in this proposal. Two examples, one with discrete time and the other with continuous one, are given and the generalization of...

Topics: General Relativity and Quantum Cosmology, Quantum Physics

Source: http://arxiv.org/abs/1701.05244

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Jun 30, 2018
06/18

by
Yi-Fu Cai; Jerome Quintin; Emmanuel N. Saridakis; Edward Wilson-Ewing

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We confront various nonsingular bouncing cosmologies with the recently released BICEP2 data and investigate the observational constraints on their parameter space. In particular, within the context of the effective field approach, we analyze the constraints on the matter bounce curvaton scenario with a light scalar field, and the new matter bounce cosmology model in which the universe successively experiences a period of matter contraction and an ekpyrotic phase. Additionally, we consider three...

Topics: High Energy Physics - Theory, Astrophysics, General Relativity and Quantum Cosmology, Cosmology and...

Source: http://arxiv.org/abs/1404.4364

Topics: Radio Program, Physical cosmology, Oral hygiene, Energy, Speculative fiction, American politicians,...

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Topics: Radio Program, General relativity, Dark matter, Galaxies, Political science, Parliament of the...

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2.0

Jun 30, 2018
06/18

by
Nobuyuki Motoyui

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The cosmological observation indicates that the effective equation of state parameter $w_{eff}$ varies with $z$: It changes from $w_{eff}>-1$ to $w_{eff}

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1411.3845

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4.0

Jun 30, 2018
06/18

by
Yi-Fu Cai; Yi Wang

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Inspired by quantum gravitational physics, the approach of non-commutative (NC) phase space leads to a modified dispersion relation of gravitational waves. This feature, if applied to the very early universe, gives rise to a modified power spectrum of primordial tensor perturbations with a suppression of power on large scales. We confront this phenomenon with the BICEP2 and Planck experiments, and show that inflation with the modified dispersion relation can simultaneously fit the observations...

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, Astrophysics, General Relativity...

Source: http://arxiv.org/abs/1404.6672

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Jun 29, 2018
06/18

by
Ramon Herrera; W. S. Hipolito-Ricaldi; Nelson Videla

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In this paper we investigate the consequences of phantom crossing considering the perturbative dynamics in models with interaction in their dark sector. By mean of a general study of gauge-invariant variables in comoving gauge, we relate the sources of instabilities in the structure formation process with the phantom crossing. In order to illustrate these relations and its consequences in more detail, we consider a specific case of an holographic dark energy interacting with dark matter. We...

Topics: Astrophysics, Cosmology and Nongalactic Astrophysics, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1607.01806

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5.0

Jun 29, 2018
06/18

by
Athanasios Bakopoulos; Panagiota Kanti

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In this work, we focus on the theory of Gravito-Electromagnetism (GEM) -- the theory that describes the dynamics of the gravitational field in terms of quantities met in Electromagnetism -- and we propose two novel forms of metric perturbations. The first one is a generalisation of the traditional GEM ansatz, and succeeds in reproducing the whole set of Maxwell's equations even for a dynamical vector potential A. The second form, the so-called alternative ansatz, goes beyond that leading to an...

Topics: High Energy Physics - Theory, Astrophysics, Cosmology and Nongalactic Astrophysics, General...

Source: http://arxiv.org/abs/1610.09819

Topics: Radio Program, Galaxies, American Roman Catholics, Real estate, American politicians, Policy, Human...

2
2.0

Jun 30, 2018
06/18

by
Sayantan Choudhury

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In this paper I provide a general framework based on $\delta N$ formalism to study the features of unavoidable higher dimensional non-renormalizable K\"ahler operators for ${\cal N}=1$ supergravity (SUGRA) during primordial inflation from the combined constraint on non-Gaussianity, sound speed and CMB dipolar asymmetry as obtained from the recent Planck data. In particular I study the nonlinear evolution of cosmological perturbations on large scales which enables us to compute the...

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, Astrophysics, General Relativity...

Source: http://arxiv.org/abs/1402.1251

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Jun 29, 2018
06/18

by
Vladimir A. Belinski

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In the present letter we indicate an extension of the pure gravity inverse scattering integration technique to the case when fermions (introduced on the base of supersymmetry) are present. In this way the integrability technique for simple ($N=1$) supergravity in two space-time dimensions coupled to the matter fields taking values in the Lie algebra of $E_{8\left( +8\right) }$ group is developed. This theory contains matter living only in one Weyl representation of $SO\left( 16\right) $ and...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1611.02924

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Topics: Radio Program, Physical cosmology, American murderers of children, American serial killers, General...

3
3.0

Jun 30, 2018
06/18

by
Naritaka Oshita; Kazuhiro Yamamoto; Sen Zhang

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We investigate Brownian motions of a particle coupled to vacuum fluctuations of a quantum field. The Unruh effect predicts that an observer in an accelerated motion sees the Minkowski vacuum as thermally excited. This addresses the problem of whether a thermal property appears in a perturbative random motion of a particle in an accelerated motion due to the coupling or not. We revisit this problem by solving the equation of motion of a particle coupled to vacuum fluctuations including the...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1403.5028

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Jun 29, 2018
06/18

by
A. Bendjoudi; N. Mebarki

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The convex hull on three points in two dimensional euclidean space of three flat edges (trihedron) was studied. The Bohr-Sommerfeld quantization of the area of space is performed. It is shown that it reproduces exactly the equidistant spacing spectrum found elsewhere.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1611.00619

Topics: Radio Program, Physical cosmology, Divided regions, East Asian countries, Theoretical physicists,...

3
3.0

Jun 30, 2018
06/18

by
Tim Taves

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We first derive the Hamiltonian for Lovelock gravity and find that it takes the same form as in general relativity when written in terms of the Misner-Sharp mass function. We then minimally couple the action to matter fields to find Hamilton's equations of motion. These are gauge fixed to be in the Painlev\'e-Gullstrand co-ordinates and are well suited to numerical studies of black hole formation. We then use these equations of motion for the massless scalar field to study the formation of...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1408.2241

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3.0

Jun 29, 2018
06/18

by
Andrea Passamonti; José A. Pons

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We study the torsional magneto-elastic oscillations of relativistic superfluid magnetars and explore the effects of a phase transition in the crust-core interface (nuclear pasta) which results in a weaker elastic response. Exploring various models with different extension of nuclear pasta phases, we find that the differences in the oscillation spectrum present in purely elastic modes (weak magnetic field), are smeared out with increasing strength of the magnetic field. For magnetar conditions,...

Topics: Astrophysics, High Energy Astrophysical Phenomena, Solar and Stellar Astrophysics, General...

Source: http://arxiv.org/abs/1606.02132

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5.0

Jun 30, 2018
06/18

by
Guillermo Ballesteros; J. Alberto Casas

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If a sizeable tensor-to-scalar ratio ~0.1 turns out to be detected and a negative running of the scalar spectral index ~0.01 is significantly required by the data, the vast majority of single field models of inflation will be ruled out. We show that a flat tree-level effective potential, lifted by radiative corrections and by the imprints of a high energy scale (in the form of non-renormalizable operators) can explain those features and produce enough inflation in the slow-roll regime.

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, Astrophysics, General Relativity...

Source: http://arxiv.org/abs/1406.3342

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2.0

Jun 30, 2018
06/18

by
David Maxwell

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The conformal method developed in the 1970s and the more recent Lagrangian and Hamiltonian conformal thin-sandwich methods are techniques for finding solutions of the Einstein constraint equations. We show that they are manifestations of a single conformal method: there is a straightforward way to convert back and forth between the parameters for these methods so that the corresponding solutions of the Einstein constraint equations agree. The unifying idea is the need to clearly distinguish...

Topics: Mathematics, Mathematical Physics, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1402.5585

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10.0

Jun 28, 2018
06/18

by
Carlos Argüelles; Nicolás Grandi; Mu-In Park

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Ho\v{r}ava gravity has been proposed as a renormalizable, higher-derivative gravity without ghost problems, by considering different scaling dimensions for space and time. In the non-relativistic higher-derivative generalization of Einstein gravity, the meaning and physical properties of black hole and membrane space-times are quite different from the conventional ones. Here, we study the singularity and horizon structures of such geometries in IR-modified Ho\v{r}ava gravity, where the...

Topics: General Relativity and Quantum Cosmology, High Energy Physics - Theory

Source: http://arxiv.org/abs/1508.04380

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2.0

Jun 30, 2018
06/18

by
Saoussen Mbarek; M. B. Paranjape

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We study the possibility of the existence of negative mass bubbles within a de Sitter space-time background with matter content corresponding to a perfect fluid. It is shown that there exist configurations of the perfect fluid, that everywhere satisfy the dominant energy condition, the Einstein equations and the equations of hydrostatic equilibrium, however asymptotically approach the exact solution of Schwarzschid-de Sitter space-time with a negative mass.

Topics: High Energy Physics - Theory, Mathematics, Mathematical Physics, General Relativity and Quantum...

Source: http://arxiv.org/abs/1407.1457

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2.0

Jun 28, 2018
06/18

by
O. Bertolami; V. Bessa; J. Páramos

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We study the possibility that inflation is driven by a massive vector field with SO(3) global symmetry nonminimally coupled to gravity. From an E^3-invariant Robertson-Walker metric we propose an Ansatz for the vector field, allowing us to study the evolution of the system. We study the behaviour of the equations of motion using the methods of the theory of dynamical systems and find exponential inflationary regimes.

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1511.03520

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2.0

Jun 28, 2018
06/18

by
John Joseph M. Carrasco; Renata Kallosh; Andrei Linde

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We construct inflationary models in the context of supergravity with orthogonal nilpotent superfields [1]. When local supersymmetry is gauge-fixed in the unitary gauge, these models describe theories with only a single real scalar (the inflaton), a graviton and a gravitino. Critically, there is no inflatino, no sgoldstino, and no sinflaton in these models. This dramatically simplifies cosmological models which can simultaneously describe inflation, dark energy and SUSY breaking.

Topics: High Energy Physics - Phenomenology, Cosmology and Nongalactic Astrophysics, Astrophysics, General...

Source: http://arxiv.org/abs/1512.00546

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2.0

Jun 30, 2018
06/18

by
Taishi Katsuragawa; Shin'ichi Nojiri

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We study the stability under the perturbation and the related anti-evaporation of the Nariai space-time in bigravity. If we impose specific condition for the solutions and parameters, we obtain asymptotically de Sitter space-time, and show the existence of the Nariai space-time as a background solution. Considering the perturbation around the Nariai space-time up to first order, we investigate the behavior of black hole horizon. We show that the anti-evaporation does not occur on the classical...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1411.1610

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3.0

Jun 29, 2018
06/18

by
Zhe Chang; Chao-Guang Huang; Zhi-Chao Zhao

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Recently, the LIGO Scientific Collaboration and Virgo Collaboration published the second observation on gravitational wave GW151226 [Phys. Rev. Lett. 116, 241103 (2016)] from the binary black hole coalescence with initial masses about 14 M$_\odot$ and 8 M$_\odot$. They claimed that the peak gravitational strain was reached at about 450 Hz, the inverse of which has been longer than the average time a photon staying in the Fabry-Perot cavities in two arms. In this case, the phase-difference of a...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1612.01615

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3.0

Jun 30, 2018
06/18

by
S. Jalalzadeh; T. Rostami; P. V. Moniz

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A framework associating quantum cosmological boundary conditions to minisuperspace hidden symmetries has been introduced in \cite{7}. The scope of the application was, notwithstanding the novelty, restrictive because it lacked a discussion involving realistic matter fields. Therefore, in the herein letter, we extend the framework scope to encompass elements from a scalar-tensor theory in the presence of a cosmological constant. More precisely, it is shown that hidden minisuperspace symmetries...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1412.6439

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2.0

Jun 30, 2018
06/18

by
Sumanta Chakraborty; Soumitra SenGupta

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This work presents a general formalism to analyze a generic bulk scalar field in a multiple warped extra-dimensional model with arbitrary number of extra dimensions. The Kaluza-Klein mass modes along with the self-interaction couplings are determined and the possibility of having lowest lying KK mode masses near TeV scale are discussed. Also some numerical values for low-lying KK modes has been presented showing explicit localization around TeV scale. It is argued that the appearance of large...

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, General Relativity and Quantum...

Source: http://arxiv.org/abs/1401.3279

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Topics: Radio Program, Physical cosmology, Energy, Edwin Hubble, Science, Johns Hopkins University,...

2
2.0

Jun 28, 2018
06/18

by
S. H. Hendi; A. Sheykhi; S. Panahiyan; B. Eslam Panah

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In this paper, we consider a linearly charged dilatonic black holes and study their thermodynamical behavior in the context of phase transition and thermodynamic geometry. We show that, depending on the values of the parameters, these type of black holes may enjoy two types of phase transition. We also find that there are three critical behaviors near the critical points for these black holes; nonphysical unstable to physical stable, large to small, and small to large black holes phase...

Topics: General Relativity and Quantum Cosmology, High Energy Physics - Theory

Source: http://arxiv.org/abs/1509.08593

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Jun 29, 2018
06/18

by
Maresuke Shiraishi; Julian B. Muñoz; Marc Kamionkowski; Alvise Raccanelli

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Most inflationary models predict primordial perturbations to be statistically isotropic and homogeneous. Cosmic microwave background (CMB) observations, however, indicate a possible departure from statistical isotropy in the form of a dipolar power modulation at large angular scales. Alternative models of inflation, beyond the simplest single-field slow-roll models, can generate a small power asymmetry, consistent with these observations. Observations of clustering of quasars show, however,...

Topics: Astrophysics, High Energy Physics - Phenomenology, Cosmology and Nongalactic Astrophysics, General...

Source: http://arxiv.org/abs/1603.01206

Topics: Radio Program, General relativity, Caribbean countries, Former Spanish colonies, Supermarkets,...

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Topics: Radio Program, Politics of the European Union, European Union law, General relativity, Political...

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Jun 28, 2018
06/18

by
Jia-An Lu

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In de Sitter (dS) gravity, where gravity is a gauge field introduced to realize the local dS invariance of the matter field, two kinds of conservation laws are derived. The first kind is a differential equation for a dS-covariant current, which unites the canonical energy-momentum (EM) and angular momentum (AM) tensors. The second kind presents a dS-invariant current which is conserved in the sense that its torsion-free divergence vanishes. The dS-invariant current unites the total (matter plus...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1508.01981

Topics: Radio Program, Health, Political science, Mass media, Community organizing, Social security, Types...

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2.0

Jun 29, 2018
06/18

by
Gonzalo A. Palma; Bastian Pradenas; Walter Riquelme; Spyros Sypsas

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Future cosmic microwave background polarization experiments will search for evidence of primordial tensor modes at large angular scales, in the multipole range $4 \leq \ell \leq 50.$ Because in that range there is some mild evidence of departures from scale invariance in the power spectrum of primordial curvature perturbations, one may wonder about the possibility of similar deviations appearing in the primordial power spectrum of tensor modes. Here we address this issue and analyze the...

Topics: High Energy Physics - Theory, Astrophysics, High Energy Physics - Phenomenology, Cosmology and...

Source: http://arxiv.org/abs/1612.09253

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8.0

Jun 28, 2018
06/18

by
O. Goldoni; M. F. A. da Silva; R. Chan

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In this paper, we have studied non stationary dust spherically symmetric spacetime, in general covariant theory ($U(1)$ extension) of the Ho\v{r}ava-Lifshitz gravity with the minimally coupling and non-minimum coupling with matter, in the post-newtonian approximation (PPN) in the infrared limit. The Newtonian prepotential $\varphi$ was assumed null. The aim of this work is to know if we can have the same spacetime, as we know in the General Relativity Theory (GRT), in Ho\v{r}ava-Lifshitz Theory...

Topic: General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1509.02685

Topics: Radio Program, Commercial crimes, Fraud, Planetary science, Physical cosmology, Crimes, Concepts in...

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Jun 28, 2018
06/18

by
A. Gruppuso; N. Kitazawa; N. Mandolesi; P. Natoli; A. Sagnotti

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String Theory and Supergravity allow, in principle, to follow the transition of the inflaton from pre-inflationary fast roll to slow roll. This introduces an infrared depression in the primordial power spectrum that might have left an imprint in the CMB anisotropy, if it occurred at accessible wavelengths. We model the effect extending $\Lambda$CDM with a scale $\Delta$ related to the infrared depression and explore the constraints allowed by {\sc Planck} data, employing also more conservative,...

Topics: High Energy Physics - Phenomenology, Cosmology and Nongalactic Astrophysics, Astrophysics, General...

Source: http://arxiv.org/abs/1508.00411

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2.0

Jun 28, 2018
06/18

by
John McDonald

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Inflation due to a non-minimally coupled scalar field with a large non-minimal coupling, as first proposed by Salopek, Bardeen and Bond (SBB), is in good agreement with the observed value of the spectral index and constraints on the tensor-to-scalar ratio. Here we explore the possibility that SBB inflation represents the late stage of a Universe which emerges from an early contracting era. We present a model in which the Universe smoothly transitions from an anamorphic contracting era to...

Topics: High Energy Physics - Theory, Cosmology and Nongalactic Astrophysics, Astrophysics, General...

Source: http://arxiv.org/abs/1511.07835

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4.0

Jun 30, 2018
06/18

by
Goffredo Chirco; Carlo Rovelli; Paola Ruggiero

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We study a class of loop-quantum-gravity states characterized by (ultra-local) thermal correlations that reproduce some features of the ultraviolet structure of the perturbative quantum field theory vacuum. In particular, they satisfy an analog of the Bisognano-Wichmann theorem. These states are peaked on the intrinsic geometry and admit a semiclassical interpretation. We study how the correlations extend on the spin-network beyond the ultra local limit.

Topics: Condensed Matter, High Energy Physics - Theory, General Relativity and Quantum Cosmology,...

Source: http://arxiv.org/abs/1408.0121

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3.0

Jun 29, 2018
06/18

by
Yun Soo Myung; Taeyoon Moon

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We investigate the inflaton decay and reheating period after the end of inflation in the non-minimal derivative coupling (NDC) model with chaotic potential. In general, this model is known to provide an enhanced slow-roll inflation caused by gravitationally enhanced friction. We find violent oscillations of Hubble parameter which induces oscillations of the sound speed squared, implying the Lagrangian instability of curvature perturbation $\zeta$ under the comoving gauge $\varphi=0$. Also, it...

Topics: High Energy Physics - Theory, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1601.03148

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3.0

Jun 30, 2018
06/18

by
Sergei V. Ketov; Takahiro Terada

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We propose new supergravity models describing chaotic Linde- and Starobinsky-like inflation in terms of a single chiral superfield. The key ideas to obtain a positive vacuum energy during large field inflation are (i) stabilization of the real or imaginary partner of the inflaton by modifying a Kahler potential, and (ii) use of the crossing terms in the scalar potential originating from a polynomial superpotential. Our inflationary models are constructed by starting from the minimal Kahler...

Topics: High Energy Physics - Theory, High Energy Physics - Phenomenology, General Relativity and Quantum...

Source: http://arxiv.org/abs/1406.0252

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3.0

Jun 30, 2018
06/18

by
J. W. Moffat

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The field equations for Scalar-Tensor-Vector-Gravity (STVG) or modified gravity (MOG) have a static, spherically symmetric black hole solution determined by the mass $M$ with two horizons. The strength of the gravitational constant is $G=G_N(1+\alpha)$ where $\alpha$ is a parameter. A regular singularity-free MOG solution is derived using a nonlinear field dynamics for the repulsive gravitational field component and a reasonable physical energy-momentum tensor. The Kruskal-Szekeres completion...

Topics: High Energy Astrophysical Phenomena, Astrophysics, General Relativity and Quantum Cosmology

Source: http://arxiv.org/abs/1412.5424

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3.0

Jun 30, 2018
06/18

by
Thibault Damour; Piotr Jaranowski

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We compute a subset of three, velocity-independent four-loop (and fourth post-Newtonian) contributions to the harmonic-coordinates effective action of a gravitationally interacting system of two point-masses. We find that, after summing the three terms, the coefficient of the total contribution is rational, due to a remarkable cancellation between the various occurrences of $\pi^2$. This result, obtained by a classical field-theory calculation, corrects the recent effective-field-theory-based...

Topics: General Relativity and Quantum Cosmology, High Energy Physics - Theory

Source: http://arxiv.org/abs/1701.02645

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2.0

Jun 30, 2018
06/18

by
A. V. Astashenok; S. Capozziello; S. D. Odintsov

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Quark star models with realistic equation of state in nonperturbative $f(R)$ gravity are considered. The mass-radius relation for $f(R)=R+\alpha R^2$ model is obtained. Considering scalar curvature $R$ as an independent function, one can find out, for each value of central density, the unique value of central curvature for which one has solutions with the required asymptotic $R\rightarrow 0$ for $r\rightarrow\infty$. In another words, one needs a fine-tuning for $R$ to achieve quark stars in...

Topics: High Energy Physics - Theory, High Energy Astrophysical Phenomena, Astrophysics, General Relativity...

Source: http://arxiv.org/abs/1412.5453

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Jun 27, 2018
06/18

by
Shahar Hod

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The spheroidal harmonics $S_{lm}(\theta;c)$ have attracted the attention of both physicists and mathematicians over the years. These special functions play a central role in the mathematical description of diverse physical phenomena, including black-hole perturbation theory and wave scattering by nonspherical objects. The asymptotic eigenvalues $\{A_{lm}(c)\}$ of these functions have been determined by many authors. However, it should be emphasized that all previous asymptotic analyzes were...

Topics: High Energy Astrophysical Phenomena, General Relativity and Quantum Cosmology, Astrophysics, High...

Source: http://arxiv.org/abs/1506.04148