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Related papers: On the stability of compact supermassive objects

200 papers

Conditions for the existence and stability of de Sitter space in modified gravity are derived by considering inhomogeneous perturbations in a gauge-invariant formalism. The stability condition coincides with the corresponding condition for…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Valerio Faraoni , Shahn Nadeau

Superfluidity in atomic Fermi gases with population imbalance has recently become an exciting research focus. There is considerable disagreement in the literature about the appropriate stability conditions for states in the phase diagram…

Superconductivity · Physics 2011-09-13 Qijin Chen , Yan He , Chih-Chun Chien , K. Levin

We investigate the stability of the non-supersymmetric solutions of type-IIB supergravity having an unwarped $AdS$ factor and $\lambda$-deformed subspaces found in arXiv:1911.12371. Among the plethora of solutions we study the perturbative…

High Energy Physics - Theory · Physics 2021-07-28 Georgios Itsios , Pantelis Panopoulos , Konstantinos Sfetsos , Dimitrios Zoakos

The hypothesis of a tiny fraction of the cosmic inventory evolving cosmologically as a degenerate Fermi gas test fluid at some dominant cosmological background is investigated. Our analytical results allow for performing preliminary…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-06 Alex E. Bernardini , E. L. D. Perico

We describe microcanonical phase transitions and instabilities of the ideal Fermi gas in general relativity at nonzero temperature confined in the interior of a spherical shell. The thermodynamic behaviour is governed by the compactness of…

General Relativity and Quantum Cosmology · Physics 2020-03-04 Zacharias Roupas , Pierre-Henri Chavanis

The classical one-phase Stefan problem (without surface tension) allows for a continuum of steady state solutions, given by an arbitrary (but sufficiently smooth) domain together with zero temperature. We prove global-in-time stability of…

Analysis of PDEs · Mathematics 2015-01-05 Mahir Hadžić , Steve Shkoller

I report on recent work concerning the existence and stability of self-gravitating spheres with anisotropic pressure. After presenting new exact solutions, Chandrasekhar's variational formalism for radial perturbations is generalized to…

Astrophysics · Physics 2009-11-10 Krsna Dev , Marcelo Gleiser

We consider the nonlinear Hartree equation for an interacting gas containing infinitely many particles and we investigate the large-time stability of the stationary states of the form $f(-\Delta)$, describing an homogeneous Fermi gas. Under…

Mathematical Physics · Physics 2016-01-20 Mathieu Lewin , Julien Sabin

We consider several classes of degenerate hyperbolic equations involving delay terms and suitable nonlinearities. The idea is to rewrite the problems in an abstract way and, using semigroup theory and energy method, we study well posedness…

Analysis of PDEs · Mathematics 2024-07-16 Alessandro Camasta , Genni Fragnelli , Cristina Pignotti

We investigate the stability and the free expansion of a trapped dipolar Fermi gas. We show that stabilizing the system relying on tuning the trap geometry is generally inefficient. We further show that the expanded density profile always…

Other Condensed Matter · Physics 2009-11-13 L. He , J. -N. Zhang , Yunbo Zhang , S. Yi

We discuss the stability of (charged) static black holes in higher-dimensional spacetimes with and without cosmological constant by using gauge-invariant master equations of the Schroedinger equation type for black hole perturbations…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Hideo Kodama , Akihiro Ishibashi

Unitarity of evolution in gravitational collapses implies existence of macroscopic stable horizonless objects. With such objects in mind, we study the effects of anisotropy of pressures on the stability of stars. We consider stars in four…

High Energy Physics - Theory · Physics 2015-10-05 S. Kalyana Rama

We prove the existence and nonlinear stability of Camm type steady states of the Vlasov-Poisson system in the gravitational case. The paper demonstrates the effectiveness of an approach to the existence and stability problem for steady…

Mathematical Physics · Physics 2007-05-23 Yan Guo , Gerhard Rein

Candidate homogeneous, isotropic superfluid or superconducting states of paired fermion species with different chemical potentials, can lead to quasiparticle excitation energies that vanish at either zero, one, or two spheres in momentum…

Superconductivity · Physics 2009-11-11 Elena Gubankova , Andreas Schmitt , Frank Wilczek

We study the dynamical stability of self-gravitating systems in presence of anisotropy. In particular, we introduce a stability criterion, in terms of the adiabatic local index, that generalizes the stability condition $<\gamma> \geq 4/3$…

General Relativity and Quantum Cosmology · Physics 2022-06-29 Giuseppe Alberti

We report on the creation of a degenerate Fermi gas consisting of a balanced mixture of atoms in three different hyperfine states of $^6$Li. This new system consists of three distinguishable Fermions with different and tunable interparticle…

Other Condensed Matter · Physics 2008-11-17 T. B. Ottenstein , T. Lompe , M. Kohnen , A. N. Wenz , S. Jochim

The theoretical description of compact structures that share some key features with mass varying particles allows for a simple analysis of equilibrium and stability for massive stellar bodies. We investigate static, spherically symmetric…

General Relativity and Quantum Cosmology · Physics 2010-01-05 Alex E. Bernardini , O. Bertolami

Analytic methods show stability of the stationary accretion of test fluids but they are inconclusive in the case of self-gravitating stationary flows. We investigate numerically stability of those stationary flows onto compact objects that…

General Relativity and Quantum Cosmology · Physics 2008-12-30 Patryk Mach , Edward Malec

We derive bounds on the deformation parameter of the $\kappa$-spacetime by analyzing the effect of non-commutativity on astrophysical model. We study compact stars, taken to be degenerate Fermi gas, in non-commutative spacetime. Using tools…

High Energy Physics - Theory · Physics 2018-03-19 E. Harikumar , Zuhair N S

We consider the model of modified gravity with dynamical torsion. This model was found to have promising stability properties about various backgrounds. The model admits a self-accelerating solution. We have shown previously that if the…

High Energy Physics - Theory · Physics 2018-03-28 V. Nikiforova