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Related papers: Analogue tachyon in Jeans Cloud

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We introduce an analogue model for a nonglobally hyperbolic spacetime in terms of a two-dimensional fluid. This is done by considering the propagation of sound waves in a radial flow with constant velocity. We show that the equation of…

General Relativity and Quantum Cosmology · Physics 2016-12-06 Ricardo A. Mosna , J. P. M. Pitelli , Maurício Richartz

We study the evolutions of selected quasi-(1+1) dimensional wavepacket solutions to the Klein-Gordon equation for a relativistic charged particle in uniform motion or accelerated by a uniform electric field in Minkowski space. We explore…

Quantum Physics · Physics 2024-02-02 Yu-Che Huang , Fong-Ming He , Shih-Yuin Lin

This paper shows that the ordinary Jeans wave number can be obtained as a limiting case of a more general approach that includes dissipative effects. Corrections to the Jeans critical mass associated to viscosity are established. Some…

Astrophysics · Physics 2016-08-16 L. S. García Colín , Alfredo Sandoval-Villalbazo

A non-canonical scalar tachyon field is a viable candidate for dark energy and has been found to be in good agreement with observational data. Background data alone cannot completely rule out degeneracy between this model and others. To…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-14 Avinash Singh , H. K. Jassal , Manabendra Sharma

We investigate de Sitter solutions of $\mathcal{N}=1$ supergravity with an F-term scalar potential near a no-scale Minkowski point, as they may in particular arise from flux compactifications in string theory. We show that a large class of…

High Energy Physics - Theory · Physics 2018-04-16 Daniel Junghans , Marco Zagermann

This paper presents a systematic treatment of the linear theory of scalar gravitational perturbations in the synchronous gauge and the conformal Newtonian (or longitudinal) gauge. It differs from others in the literature in that we give, in…

Astrophysics · Physics 2015-06-24 Chung-Pei Ma , Edmund Bertschinger

In this paper, we have considered closed string tachyon model with a constant dilaton field and interacted it with Chaplygin gas for evaluating cosmology parameters. The model has been studied in $26$-dimensional that its $22$-dimensional…

General Relativity and Quantum Cosmology · Physics 2013-12-16 Ali R. Amani , Celia Escamilla-Rivera , H. R. Faghani

The Lemaitre-Tolman-Bondi solution has received much attention as a possible alternative to Dark Energy, as it is able to account for the apparent acceleration of the Universe without any exotic matter content. However, in order to make…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Chris Clarkson , Timothy Clifton , Sean February

We study a quantum Boltzmann-Condensation system that describes the evolution of the interaction between a well formed Bose-Einstein condensate and the quasi-particles cloud. The kinetic model is valid for a dilute regime at which the…

Analysis of PDEs · Mathematics 2018-05-22 Ricardo Alonso , Irene M. Gamba , Minh-Binh Tran

The discrete Klein-Gordon equation on a two-dimensional square lattice satisfies an $\ell^1 \mapsto \ell^\infty$ dispersive bound with polynomial decay rate $|t|^{-3/4}$. We determine the shape of the light cone for any choice of the mass…

Analysis of PDEs · Mathematics 2015-04-13 Vita Borovyk , Michael Goldberg

We consider a quasi-one-dimensional two-component Bose-Einstein condensate subject to a coherent coupling between its components, such as realized in spin-orbit coupled condensates. We study how nonlinearity modifies the dynamics of the…

Quantum Gases · Physics 2016-04-20 T. Congy , A. Kamchatnov , N. Pavloff

Simple analytic solution to cubic Neveu-Schwarz String Field Theory including the $GSO(-)$ sector is presented. This solution is an analog of the Erler-Schnabl solution for bosonic case and one of the authors solution for the pure $GSO(+)$…

High Energy Physics - Theory · Physics 2015-05-18 I. Ya. Aref'eva , R. V. Gorbachev

We investigate a string theoretic cosmological model in the context of the gauged Wess-Zumino-Witten model. Our model is based on a product of non-compact coset space and a spectator flat space; $[SL(2,R)/U(1)]_k \times {\bf R}^2$. We…

High Energy Physics - Theory · Physics 2011-06-09 Sunggeun Lee , Soonkeon Nam

We report on experiments that demonstrate dynamical instability in a Bose-Einstein condensate at the band-edge of a one-dimensional optical lattice. The instability manifests as rapid depletion of the condensate and conversion to a thermal…

Other Condensed Matter · Physics 2009-11-13 Andrew J. Ferris , Matthew J. Davis , Reece W. Geursen , P. Blair Blakie , Andrew C. Wilson

In the present work we examine the dynamics of a model for oscillons in 1-dimensional spacetime field theories with a cubic nonlinearity. We utilize a reduction of the model to first and third harmonics, which leads to a reduced partial…

Pattern Formation and Solitons · Physics 2025-08-19 A. G. Stefanov , M. Stanislavova , J. Cuevas-Maraver , P. G. Kevrekidis

We present a detailed study of cosmological effects of homogeneous tachyon matter coexisting with non-relativistic matter and radiation, concentrating on the inverse square potential and the exponential potential for the tachyonic scalar…

Astrophysics · Physics 2011-05-05 J. S. Bagla , H. K. Jassal , T. Padmanabhan

Bose-Einstein condensation of antikaons in cold and dense beta-equilibrated matter under the influence of strong magnetic fields is studied within a relativistic mean field model. For magnetic fields $> 5 \times 10^{18}$G, the phase spaces…

Astrophysics · Physics 2014-10-13 Prantick Dey , Abhijit Bhattacharyya , Debades Bandyopadhyay

We consider the evolution of relativistic perturbations in the Einstein-de Sitter cosmological model, including second-order effects. The perturbations are considered in two different settings: the widely used synchronous gauge and the…

Astrophysics · Physics 2009-10-30 S. Matarrese , S. Mollerach , M. Bruni

Axion-like fields heavier than about $10^{-27}$eV are expected to oscillate in the radiation dominated epoch when the Hubble parameter drops below their mass. Considering the Chern-Simons coupling with a dark gauge boson, large amount of…

High Energy Physics - Phenomenology · Physics 2021-05-26 Borna Salehian , Mohammad Ali Gorji , Shinji Mukohyama , Hassan Firouzjahi

It has recently been demonstrated [A. Giusti, Phys. Rev. D 101, 124029 (2020)] that characteristic traits of Milgrom's modified Newtonian dynamics (MOND) can be replicated from an entirely distinct framework: a fractional variant of…

General Relativity and Quantum Cosmology · Physics 2024-05-21 Kamel Ourabah
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