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In order to imitate anisotropic medium of a condensed matter system, we take into account an Einstein-Maxwell-dilaton-axion model as a dual gravity theory where the anisotropy is caused by different momentum relaxations. This gravity model…

High Energy Physics - Theory · Physics 2016-10-19 Sunly Khimphun , Bum-Hoon Lee , Chanyong Park

By using Bianchi I type of homogenous and anisotropic background metric having cylindrical symmetry in $x$ direction of a local cartesian coordinates system, we solve metric field equations for a non-minimally coupled Einstein-Maxwell…

General Relativity and Quantum Cosmology · Physics 2020-12-08 Hossein Ghaffarnejad , Hoda Gholipour

The energy level of the exciton around the $\Gamma$ point in CaF$_2$ at about 11.1 eV was investigated by reflection measurements on oriented surfaces using dispersed synchrotron radiation. A small but clear energy shift of the exciton…

Materials Science · Physics 2009-11-10 M. Letz , L. Parthier , A. Gottwald , M. Richter

Preliminary results from the STAR collaboration of the azimuthal anisotropy $(v_{2})$ of $\pi^{0}$ and direct photon ($\gamma_{dir}$) at high transverse momentum (p$_{T}$) from Au+Au collisions at center-of-mass energy…

Nuclear Experiment · Physics 2011-02-18 Ahmed M. Hamed

In this paper, we study the effective pressure of the $N$-dimensional FRW(Friedmann-Robertson-Walker) universe in Einstein gravity, Gauss-Bonnet gravity, and Lovelock gravity. The effective pressure is defined by $P_{eff}:=-d E/d V$, where…

General Relativity and Quantum Cosmology · Physics 2025-12-29 Shi-Bei Kong

We consider the non-minimal model of gravity in $Y(R) F^2$-form. We investigate a particular case of the model, for which the higher order derivatives are eliminated but the scalar curvature $R$ is kept to be dynamical via the constraint…

General Relativity and Quantum Cosmology · Physics 2017-11-17 Muzaffer Adak , Ozgur Akarsu , Tekin Dereli , Ozcan Sert

We derive here the metric for Einstein's static universe (ESU) directly from Einstein equation, i.e., by considering both $G_{ik}$ and $T_{ik}$. We find that in order that the fluid pressure and acceleration are {\em uniform} and finite…

General Physics · Physics 2008-08-19 Abhas Mitra

Using scalar-vector-tensor Brans Dicke (VBD) gravity [3] in presence of self interaction BD potential $V(\phi)$ and perfect fluid matter field action we solve corresponding field equations via dynamical system approach for flat Friedmann…

General Physics · Physics 2017-03-08 H. Ghaffarnejad , E. Yaraie

We examine the gravitational properties of Lamb shift energies. Using available experimental data we show that these energies have a standard gravitational behavior at the level of $\sim 10^{-5}$. We are motivated by the point of view that…

General Relativity and Quantum Cosmology · Physics 2009-09-28 Eduard Masso

We measure the anisotropy of the redshift-space power spectrum in the 1.2-Jy and QDOT redshift surveys of IRAS-selected galaxies. On large scales, this anisotropy is caused by coherent peculiar motions, and gravitational instability theory…

Astrophysics · Physics 2015-06-24 Shaun Cole , Karl B. Fisher , David H. Weinberg

A high spectral resolution observation of the diffuse X-ray background in the 60 - 1000 eV energy range has been made using an array of thirty-six 1 mm^2 micro-calorimeters flown on a sounding rocket. Detector energy resolution ranged from…

We analyze the sidereal daily variations observed between 1985 and 2006 at Matsushiro, Japan (MAT) and between 1993 and 2005 at Liapootah, Tasmania (LPT). These stations comprise the two hemisphere network (THN) of underground muon…

Astrophysics · Physics 2008-11-05 K. Munakata , N. Matsumoto , S. Yasue , C. Kato , S. Mori , M. Takita , M. L. Duldig , J. E. Humble , J. Kota

An extended framework of gravity, in which the first Friedmann equation is satisfied up to some constant due to violation of gauge invariance, is tested against astrophysical data: Supernovae Type-Ia, Cosmic Chronometers, and Gamma-ray…

General Physics · Physics 2020-08-24 Balakrishna S. Haridasu , S. L. Cherkas , V. L. Kalashnikov

We experimentally show the spectrally averaged nonlinear refractive index and absorption coefficient for liquid water, water vapor, {\alpha}-pinene, and Si using a full-phase analysis in the terahertz regime through a standard time-domain…

We evaluate the Wightman function, the mean field squared and the vacuum expectation value (VEV) of the energy-momentum tensor for a scalar field with Robin boundary condition on a spherical shell in the background of a constant negative…

High Energy Physics - Theory · Physics 2014-09-29 S. Bellucci , A. A. Saharian , N. A. Saharyan

The Degree Angular Scale Interferometer (\dasi) has measured the power spectrum of the Cosmic Microwave Background anisotropy over the range of spherical harmonic multipoles 100<l<900. We compare this data, in combination with the COBE-DMR…

We study the electron-positron vacuum in a strong magnetic field $B$ in parallel with Casimir effect. Use is made of the energy-momentum tensor, taken as the zero temperature and zero density limit of the relativistic quantum statistical…

High Energy Physics - Phenomenology · Physics 2007-05-23 H. Perez Rojas , E. Rodriguez Querts

We present for the first time hourly variations of the spatial density gradient of 50 GeV cosmic rays within a sample solar rotation period in 2006. By inversely solving the transport equation, including diffusion, we deduce the gradient…

In the standard diffusive picture for transport of cosmic rays (CRs), a gradient in the CR density induces a typically small, dipolar anisotropy in their arrival directions. This has been widely advertised as a tool for finding nearby…

High Energy Astrophysical Phenomena · Physics 2015-01-15 Philipp Mertsch , Stefan Funk

We study the behavior of the vacuum in Euclidean dynamical triangulations (EDT). Algorithmic improvements and better lattice spacing determinations allow us to test the properties of the emergent de Sitter geometries of our simulations to…

High Energy Physics - Lattice · Physics 2025-05-21 Mingwei Dai , Walter Freeman , Jack Laiho , Marc Schiffer , Judah Unmuth-Yockey