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After transition from the Dirac equation to the Schr\"{o}dinger-type relativistic equation with effective potentials of the Schwarzschild and Reissner-Nordstr\"{o}m (RN) fields, the existence of the stationary state of fermions with real…

General Relativity and Quantum Cosmology · Physics 2018-08-29 V. P. Neznamov , I. I. Safronov , V. E. Shemarulin

The quark matter may have great implications in astrophysical studies, which could appear in the early Universe, in compact stars, and/or as cosmic rays. After a general review of astrophysical quark matter, the density-dominated quark…

Astrophysics · Physics 2014-10-13 R. X. Xu

The standard model of cosmology suggests the existence of two components, "dark matter" and "dark energy", which determine the fate of the Universe. Their nature is still under investigation, and no direct proof of their existences has…

Astrophysics · Physics 2009-07-09 A. Arbey

In this article the particle creation process of scalar and spin 1/2 particles in a spatially open cosmological model associated with a universe filled by radiation and dustlike matter. The Klein-Gordon and Dirac equations are solved via…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Victor M. Villalba

Quantum dynamics of a Dirac particle in a 1D box with moving wall is studied. Dirac equation with time-dependent boundary condition is mapped onto that with static one, but with time-dependent mass. Exact analytical solution of such…

Quantum Physics · Physics 2024-06-20 J. Dittrich , S. Rakhmanov , D. Matrasulov

We study the Friedmann-Robertson-Walker cosmological model to investigate non-smooth curvatures associated with multiple discontinuities involved in the evolution of the universe, by exploiting Lorentzian warped product scheme. Introducing…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Soon-Tae Hong

The formalism to treat quantization and evolution of cosmological perturbations of multiple fluids is described. We first construct the Lagrangian for both the gravitational and matter parts, providing the necessary relevant variables and…

General Relativity and Quantum Cosmology · Physics 2016-02-01 Patrick Peter , Nelson Pinto-Neto , Sandro Dias Pinto Vitenti

The spectrum of bound and scattering states of the one dimensional Dirac Hamiltonian describing fermions distorted by a static background built from two Dirac delta potentials is studied. A distinction will be made between mass-spike and…

Quantum Physics · Physics 2023-08-30 Lucía Santamaría-Sanz

We discuss certain issues related to the limitations of density parameters for a ``radiation''-like contribution to the Friedmann equation using kinematical or geometrical measurements. We analyse the observational constraint of a negative…

Astrophysics · Physics 2008-11-26 Wlodzimierz Godlowski , Marek Szydlowski

We propose that the cold dark matter (CDM) is composed entirely of quark matter, arising from a cosmic quark-hadron transition. We denote this phase as "quasibaryonic", distinct from the usual baryons. We show that compact gravitational…

Recent experimental breakthroughs in trapping, cooling and controlling ultracold gases of polar molecules, magnetic and Rydberg atoms have paved the way toward the investigation of highly tunable quantum systems, where anisotropic,…

Quantum Gases · Physics 2015-02-11 M. A. Baranov , M. Dalmonte , G. Pupillo , P. Zoller

Cosmological models with Lagrange multipliers are appealing because they could explain the behaviour of the dark sector in a unified way. In this work we analyse extensions to the "Dust of Dark Energy model" proposed in arXiv:1003.5751 by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Antonella Cid , Pedro Labrana

In quantum field theory there exist states for which the energy density is negative. It is important that these negative energy densities satisfy constraints, such as quantum inequalities, to minimize possible violations of causality, the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Dan N. Vollick

These lecture notes aim to provide an introduction to dark matter from the perspective of astrophysics/cosmology. We start with a rapid overview of cosmology, including the evolution of the Universe, its thermal history and structure…

High Energy Physics - Phenomenology · Physics 2022-01-26 Anne M. Green

We consider Hilbert's sixth problem on the axiomatization of physics starting with a higher degree Heisenberg commutation relation involving the Dirac operator and the Feynman slash of scalar fields. The two sided version of the commutation…

High Energy Physics - Theory · Physics 2018-06-13 Ali H. Chamseddine

We study a spatially flat Friedmann model containing a pressureless perfect fluid (dust) and a scalar field with an unbounded from below potential of the form $V(\fii)=W_0 - V_0\sinh(\sqrt{3/2}\kappa\fii)$, where the parameters $W_0$ and…

General Relativity and Quantum Cosmology · Physics 2009-11-10 V. R. Gavrilov , V. N. Melnikov , S. T. Abdyrakhmanov

The Friedman equation is solved for a universe contains hotdark matter and cold dark matter. In this scenario, hot-dark matter drives an accelerating universe no cold dark matter.

Astrophysics · Physics 2007-05-23 Abbas Farmany , Amin Farmany , Mohammad Mahmoodi

Confining ultracold gases in cavities creates a paradigm of quantum trapping potentials. We show that this allows to bridge models with global collective and short-range interactions as novel quantum phases possess properties of both. Some…

Quantum Gases · Physics 2015-12-14 Santiago F. Caballero-Benitez , Igor B. Mekhov

Part I of this paper introduced the infinite dimensional Lagrange-Dirac theory for physical systems on the space of differential forms over a smooth manifold with boundary. This approach is particularly well-suited for systems involving…

Symplectic Geometry · Mathematics 2025-11-11 François Gay-Balmaz , Álvaro Rodríguez Abella , Hiroaki Yoshimura

Quantum simulation is a powerful tool to study a variety of problems in physics, ranging from high-energy physics to condensed-matter physics. In this article, we review the recent theoretical and experimental progress in quantum simulation…

Quantum Gases · Physics 2012-03-28 Dan-Wei Zhang , Zi-Dan Wang , Shi-Liang Zhu
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