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We study the horizontal expansion of vertically confined ultra-cold atoms in the presence of disorder. Vertical confinement allows us to realize a situation with a few coupled harmonic oscillator quantum states. The disordered potential is…

This paper is devoted to study the accelerated expansion of the universe by exploring the Brans-Dicke parameter in different eras. For this purpose, we take FRW universe model with viscous fluid (without potential) and Bianchi type I…

General Relativity and Quantum Cosmology · Physics 2015-06-15 M. Sharif , Saira Waheed

Anisotropy of the permeability tensor in statistically uniform porous media of sizes used in typical computer simulations is studied. Although such systems are assumed to be isotropic by default, we show that de facto their anisotropic…

Fluid Dynamics · Physics 2015-05-13 Zbigniew Koza , Maciej Matyka , Arzhang Khalili

We present theoretical calculations of the thermal conductivity for the accidental degeneracy and enlarged symmetry group models that have been proposed to explain the phase diagram of UPt3. The order parameters for these models possess…

Superconductivity · Physics 2011-04-08 M. J. Graf , S. -K. Yip , J. A. Sauls

The kinematic approach to cosmological tests provides a direct evidence to the present accelerating stage of the universe which does not depend on the validity of general relativity, as well as on the matter-energy content of the Universe.…

Astrophysics · Physics 2009-03-12 J. V. Cunha

Under the assumption that they are standard(isable) candles, the lightcurves of Type Ia supernovae have been analyzed in the framework of the standard Friedmann-Lema\^itre-Robertson-Walker cosmology to conclude that the expansion rate of…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-14 Mohamed Rameez

The transition redshift (deceleration/acceleration) is discussed by expanding the deceleration parameter to first order around its present value. A detailed study is carried out by considering two different parameterizations: $q=q_0 + q_1z$…

Astrophysics · Physics 2011-02-11 J. V. Cunha , J. A. S. Lima

We consider an anisotropic inhomogeneous model to simulate measured vertical-seismic-profile traveltimes. In this model, we assume that velocity increases linearly with depth and anisotropy is the result of elliptical velocity dependence.…

Geophysics · Physics 2020-12-08 Ayiaz Kaderali , Theodore Stanoev

We evaluated the emission of a low-mass particle in the system (atomic) transition for the case when the particle Lorentz factor is $10^{18}$ and found that the angular distribution of emission in the laboratory inertial system is strongly…

High Energy Physics - Phenomenology · Physics 2026-01-13 B. Wojtsekhowski

In this paper, we derive observational constraints on an anisotropic $w$CDM model from observational data including Baryonic Acoustic Oscillations (BAOs), Cosmic Chronometer (CC), Big Bang Nucleosynthesis (BBN), Pantheon Plus (PP)…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-17 Vikrant Yadav , Santosh Kumar Yadav , Rajpal

By using the supernovae type Ia data we study influence of the anisotropy (although low) on the evolution of the universe and compare ${\Lambda}$CDM model with 6 representative parametrizations of the recent Hubble expansion history $H(z)$.…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-05 H. Hossienkhani , H. Yousefi , N. Azimi

If the augmented density of a spherical anisotropic system is assumed to be multiplicatively separable to functions of the potential and the radius, the radial function, which can be completely specified by the behavior of the anisotropy…

Cosmology and Nongalactic Astrophysics · Physics 2011-07-21 J. An

The kinematic expansion history of the universe is investigated by using the 307 supernovae type Ia from the Union Compilation set. Three simple model parameterizations for the deceleration parameter (constant, linear and abrupt transition)…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-13 A. C. C. Guimarães , J. V. Cunha , J. A. S. Lima

In this letter, we report the observational constraints on a Bianchi type I anisotropic extension of $w$CDM model with spatial curvature from observational data including Baryon Acoustic Oscillations (BAO), Cosmic chronometers (CC), Big…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-21 Vikrant Yadav , Rajpal , Pardeep , Manish Yadav , Santosh Kumar Yadav

Among various phenomenological $\Lambda$ models, a time-dependent model $\dot \Lambda\sim H^3$ is selected here to investigate the $\Lambda$-CDM cosmology. Using this model the expressions for the time-dependent equation of state parameter…

General Relativity and Quantum Cosmology · Physics 2011-01-25 Saibal Ray , Maxim Khlopov , Utpal Mukhopadhyay , Partha Pratim Ghosh

Recently, semidefinite programming performance estimation has been employed as a strong tool for the worst-case performance analysis of first order methods. In this paper, we derive new non-ergodic convergence rates for the alternating…

Optimization and Control · Mathematics 2023-05-25 Moslem Zamani , Hadi Abbaszadehpeivasti , Etienne de Klerk

Using stochastic conformal mappings we study the effects of anisotropic perturbations on diffusion limited aggregation (DLA) in two dimensions. The harmonic measure of the growth probability for DLA can be conformally mapped onto a constant…

Statistical Mechanics · Physics 2009-11-10 M. N. Popescu , H. G. E. Hentschel , F. Family

We study the three-dimensional Anderson model of localization with anisotropic hopping, i.e. weakly coupled chains and weakly coupled planes. In our extensive numerical study we identify and characterize the metal-insulator transition using…

Disordered Systems and Neural Networks · Physics 2016-08-15 Frank Milde , Rudolf A. Römer , Michael Schreiber

The adaptive perturbation chooses a non-standard decomposition. The Hamiltonian becomes a sum of solvable and perturbation parts. We calculate the spectrum using the adaptive perturbation method at the leading-order to compare to numerical…

Quantum Physics · Physics 2021-07-08 Chen-Te Ma

In this paper, we use the Cosmokinematics approach to study the accelerated expansion of the Universe. This is a model independent approach and depends only on the assumption that the Universe is homogeneous and isotropic and is described…

General Relativity and Quantum Cosmology · Physics 2016-01-06 Nisha Rani , Deepak Jain , Shobhit Mahajan , Amitabha Mukherjee , Nilza Pires