Gravitational Particle Production in Massive Chaotic Inflation and the Moduli Problem
Jaume de Haro and Emilio Elizalde
Particle production from vacuum fluctuations during inflation is briefly revisited. The moduli problem occurring with light particles produced at the end of inflation is addressed, namely, the fact that some results are in disagreement with nucleosynthesis constrains. A universal solution to this pr ... [Phys. Rev. Lett. 108, 061303 ] published .
Bianchi class B spacetimes with electromagnetic fields
Kei Yamamoto
We carry out a thorough analysis on a class of cosmological space-times which admit three spacelike Killing vectors of Bianchi class B and contain electromagnetic fields. Using dynamical system analysis, we show that a family of electro-vacuum plane-wave solutions of the Einstein-Maxwell equations i ... [Phys. Rev. D 85, 043510 ] published .
Entropy Generation across Earth's Collisionless Bow Shock
G. K. Parks, E. Lee, M. McCarthy, M. Goldstein, S. Y. Fu et al.
Earth's bow shock is a collisionless shock wave but entropy has never been directly measured across it. The plasma experiments on Cluster and Double Star measure 3D plasma distributions upstream and downstream of the bow shock allowing calculation of Boltzmann's entropy function H and his famous H t ... [Phys. Rev. Lett. 108, 061102 ] published .
Interacting dark energy: Constraints and degeneracies
Timothy Clemson, Kazuya Koyama, Gong-Bo Zhao, Roy Maartens, and Jussi Valiviita
In standard cosmologies, dark energy (DE) interacts only gravitationally with dark matter (DM). There could be a nongravitational interaction in the dark sector, leading to changes in the effective DE equation of state, in the redshift dependence of the DM density and in structure formation. We use ... [Phys. Rev. D 85, 043007 ] published .
Compressible hydromagnetic nonlinearities in the predecoupling plasma
Massimo Giovannini
The adiabatic inhomogeneities of the scalar curvature lead to a compressible flow affecting the dynamics of the hydromagnetic nonlinearities. The influence of the plasma on the evolution of a putative magnetic field is explored with the aim of obtaining an effective description valid for sufficientl ... [Phys. Rev. D 85, 043006 ] published .
Dark radiation from particle decays during big bang nucleosynthesis
Justin L. Menestrina and Robert J. Scherrer
CMB observations suggest the possibility of an extra dark radiation component, while the current evidence from big bang nucleosynthesis (BBN) is more ambiguous. Dark radiation from a decaying particle can affect these two processes differently. Early decays add an additional radiation component to b ... [Phys. Rev. D 85, 047301 ] published .
Disentangling non-Gaussianity, bias, and general relativistic effects in the galaxy distribution
Marco Bruni, Robert Crittenden, Kazuya Koyama, Roy Maartens, Cyril Pitrou et al.
Local non-Gaussianity, parametrized by f, introduces a scale-dependent bias that is strongest at large scales, precisely where general relativistic (GR) effects also become significant. With future data, it should be possible to constrain f=[script O](1) with high redshift surveys. GR corrections to ... [Phys. Rev. D 85, 041301 ] published .
Cosmological tests of general relativity: A principal component analysis
Alireza Hojjati, Gong-Bo Zhao, Levon Pogosian, Alessandra Silvestri, Robert Crittenden et al.
The next generation of weak lensing surveys will trace the evolution of matter perturbations and gravitational potentials from the matter dominated epoch until today. Along with constraining the dynamics of dark energy, they will probe the relations between matter overdensities, local curvature, and ... [Phys. Rev. D 85, 043508 ] published .
Observational constraints on the averaged universe
Chris Clarkson, Timothy Clifton, Alan Coley, and Rockhee Sung
Averaging in general relativity is a complicated operation, due to the general covariance of the theory and the nonlinearity of Einstein's equations. The latter of these ensures that smoothing spacetime over cosmological scales does not yield the same result as solving Einstein's equations with a sm ... [Phys. Rev. D 85, 043506 ] published .
Statistics of bipolar representation of CMB maps
Nidhi Joshi, Aditya Rotti, and Tarun Souradeep
Gaussianity of temperature fluctuations in the Cosmic Microwave Background (CMB) implies that the statistical properties of the temperature field can be completely characterized by its two-point correlation function. The two-point correlation function can be expanded in full generality in the Bipola ... [Phys. Rev. D 85, 043004 ] published .
Observing Lense-Thirring Precession in Tidal Disruption Flares
Nicholas Stone and Abraham Loeb
When a star is tidally disrupted by a supermassive black hole (SMBH), the streams of liberated gas form an accretion disk after their return to pericenter. We demonstrate that Lense-Thirring precession in the spacetime around a rotating SMBH can produce significant time evolution of the disk angular ... [Phys. Rev. Lett. 108, 061302 ] published .
Erratum: Observational constraints on the ultrahigh energy cosmic neutrino flux from the second flight of the ANITA experiment [Phys. Rev. D 82 022004 (2010)]
P. W. Gorham, P. Allison, B. M. Baughman, J. J. Beatty, K. Belov et al.
Abstract not available. [Phys. Rev. D 85, 049901 ] published .
Entropic force scenarios and eternal inflation
Taotao Qiu and Emmanuel N. Saridakis
We examine various entropic inflation scenarios, under the light of eternality. After describing the inflation realization and the normal condition for inflation to last at the background level, we investigate the conditions for eternal inflation with the effect of thermal fluctuations produced from ... [Phys. Rev. D 85, 043504 ] published .
Inflation with large supergravity corrections
Anupam Mazumdar, Seshadri Nadathur, and Philip Stephens
It is well known that large Hubble-induced supergravity corrections to the inflaton field can ruin the flatness of the potential, thus creating a tension between slow-roll inflation and supergravity. In this paper we show that it is possible to obtain a cosmologically flat direction, embedded within ... [Phys. Rev. D 85, 045001 ] published .
Phase transition and monopole production in supergravity inflation
Kohei Kamada, Kazunori Nakayama, and Jun'ichi Yokoyama
In F-term supergravity inflation models, scalar fields other than the inflaton generically receive a Hubble-induced mass, which may restore gauge symmetries during inflation and phase transitions may occur during or after inflation as the Hubble parameter decreases. We study monopole (and domain wal ... [Phys. Rev. D 85, 043503 ] published .
Extragalactic and galactic gamma rays and neutrinos from annihilating dark matter
Rouzbeh Allahverdi, Sheldon Campbell, and Bhaskar Dutta
We describe cosmic gamma-ray and neutrino signals of dark matter annihilation, explaining how the complementarity of these signals provides additional information that, if observable, can enlighten the particle nature of dark matter. This is discussed in the context of exploiting the separate galact ... [Phys. Rev. D 85, 035004 ] published .
Chameleon effects on small scale structure and the baryonic Jeans mass
Katherine Jones-Smith
In the framework of Newtonian cosmology or general relativity it is simple to derive a mass scale below which collapsed structures are relatively devoid of baryons. We examine how the inclusion of a chameleon scalar field affects this baryonic Jeans mass, bearing in mind both the canonical case of a ... [Phys. Rev. D 85, 043502 ] published .
Renormalization group improvement of scalar field inflation
Adriano Contillo, Mark Hindmarsh, and Christoph Rahmede
We study quantum corrections to Friedmann-Robertson-Walker cosmology with a scalar field under the assumption that the dynamics are subject to renormalization group improvement. We use the Bianchi identity to relate the renormalization group scale to the scale factor and obtain the improved cosmolog ... [Phys. Rev. D 85, 043501 ] published .
Towards the use of the most massive black hole candidates in active galactic nuclei to test the Kerr paradigm
Cosimo Bambi
The supermassive objects in galactic nuclei are thought to be the Kerr black holes predicted by general relativity, although a definite proof of their actual nature is still lacking. The most massive objects in AGN (M~10 M) seem to have a high radiative efficiency (eta~0.4) and a moderate mass accre ... [Phys. Rev. D 85, 043001 ] published .
A century of cosmic rays
Per Carlson
Abstract not available. [Phys. Today 65, 30 (2012)] published Wed Feb 1, 2012.
Premature Nobel Prize decision?
Yousaf M. Butt
Abstract not available. [Phys. Today 65, 10 (2012)] published Wed Feb 1, 2012.
Efficiency of a wide-area survey in achieving short- and long-term warning for small impactors. (arXiv:1110.3964v2 [astro-ph.IM] UPDATED)
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