English
Related papers

Related papers: Instabilities in Thermal Gravity with a Cosmologic…

200 papers

Gravitational instabilities of isothermal spheres are studied in the presence of a positive or negative cosmological constant, in the Newtonian limit. In gravity, the statistical ensembles are not equivalent. We perform the analysis both in…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-20 Minos Axenides , George Georgiou , Zacharias Roupas

A finite and unitary nonlocal formulation of quantum gravity is applied to the cosmological constant problem. The entire functions in momentum space at the graviton-standard model particle loop vertices generate an exponential suppression…

General Relativity and Quantum Cosmology · Physics 2016-02-08 J. W. Moffat

We calculate in a general background gauge, to one-loop order, the leading logarithmic contribution from the graviton self-energy at finite temperature $T$, extending a previous analysis done at $T=0$. The result, which has a transverse…

High Energy Physics - Theory · Physics 2023-05-02 F. T. Brandt , J. Frenkel , D. G. C. McKeon , G. S. S. Sakoda

Analytical solutions of nonminimally coupled scalar field cosmology corresponding to critical scalar field values constitute a potential challenge to the recent first-order thermodynamics of scalar-tensor gravity (a formalism picturing…

General Relativity and Quantum Cosmology · Physics 2022-07-11 Valerio Faraoni , Pierre-Antoine Graham , Alexandre Leblanc

A finite quantum gravity theory is used to resolve the cosmological constant problem. A fundamental quantum gravity scale, \Lambda_G \leq 10^{-3} eV, is introduced above which the quantum corrections to the vacuum energy density coupled to…

High Energy Physics - Phenomenology · Physics 2007-05-23 J. W. Moffat

It is shown how quantum field theory at finite temperature can be used to set up self-consistent and gauge invariant equations for cosmological perturbations sustained by an ultrarelativistic plasma. While in the collisionless case, the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Anton K. Rebhan

In the saddle point approximation, the Euclidean path integral for quantum gravity closely resembles a thermodynamic partition function, with the cosmological constant $\Lambda$ playing the role of temperature and the ``density of…

General Relativity and Quantum Cosmology · Physics 2010-04-28 Steven Carlip

Quantum gravitational effects in loop quantum cosmology lead to a resolution of the initial singularity and have the potential to solve the horizon problem and generate a quasi scale-invariant spectrum of density fluctuations. We consider…

Astrophysics · Physics 2008-11-26 Joao Magueijo , Parampreet Singh

We consider a question motivated by the third law of thermodynamics: can there be a local temperature arbitrarily close to absolute zero in a nonequilibrium quantum system? We consider nanoscale quantum conductors with the source reservoir…

Mesoscale and Nanoscale Physics · Physics 2016-03-01 Abhay Shastry , Charles A. Stafford

We study the question of stability of the ground state of a scalar theory which is a generalization of the phi^3 theory and has some similarity to gravity with a cosmological constant. We show that the ground state of the theory at zero…

High Energy Physics - Theory · Physics 2008-12-18 F. T. Brandt , Ashok Das , J. Frenkel

The thermodynamic instabilities of the self-gravitating, classical ideal gas are studied in the case of static, spherically symmetric configurations in General Relativity taking into account the Tolman-Ehrenfest effect. One type of…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Zacharias Roupas

Thermodynamical stability of fluid spheres is studied in the presence of a cosmological constant, both in the Newtonian limit, as well as in General Relativity. In all cases, an increase of the cosmological constant tends to stabilize the…

General Relativity and Quantum Cosmology · Physics 2013-05-22 Zacharias Roupas

The high temperature limit of the 3-graviton vertex function is studied in thermal quantum gravity, to one loop order. The leading ($T^4$) contributions arising from internal gravitons are calculated and shown to be twice the ones…

High Energy Physics - Phenomenology · Physics 2009-10-22 F. T. Brandt , J. Frenkel

We present here how the gravothermal or Antonov's instability, which was originally formulated in the microcanonical ensemble, is modified in the presence of a cosmological constant and in the canonical ensemble. In contrast to the…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-22 Minos Axenides , George Georgiou , Zacharias Roupas

In this work, we develop an analytical framework to understand quantum friction across distinct stability regimes, providing approximate expressions for frictional forces both in the deep stable regime and near the critical threshold of…

Quantum Physics · Physics 2025-02-10 Daigo Oue , Boris Shapiro , Mário G. Silveirinha

We investigate the effect of a cosmological constant on the gravothermal catastrophe in the Newtonian limit. A negative cosmological constant acts as a thermodynamic `destabilizer'. The Antonov radius gets smaller and the instability…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-05 Minos Axenides , George Georgiou , Zacharias Roupas

Thermal duality, which relates the physics of closed strings at temperature T to the physics at the inverse temperature 1/T, is one of the most intriguing features of string thermodynamics. Unfortunately, the classical definitions of…

High Energy Physics - Theory · Physics 2009-11-10 Keith R. Dienes , Michael Lennek

We consider blocks of quantum spins in a chain at thermal equilibrium, focusing on their properties from a thermodynamical perspective. Whereas in classical systems the temperature behaves as an intensive magnitude, a deviation from this…

Quantum Physics · Physics 2015-05-13 A. Garcia-Saez , A. Ferraro , A. Acin

We re-examine the black hole solutions in classical theories of dilaton gravity in two dimensions. We consider an arbitrary dilaton potential such that there are black hole solutions asymptotic at infinity to the nearly $\mathrm{AdS}_2$…

High Energy Physics - Theory · Physics 2020-06-24 Edward Witten

The quantum gravitational contribution to the renormalization group behavior of the electric charge in Einstein-Maxwell theory with a cosmological constant is considered. Quantum gravity is shown to lead to a contribution to the running…

High Energy Physics - Theory · Physics 2008-11-26 David J. Toms
‹ Prev 1 2 3 10 Next ›