56 research outputs found
Viscous Modified Cosmic Chaplygin Gas Cosmology
In this paper we construct modified cosmic Chaplygin gas which has viscosity.
We use exponential function method to solve non-linear equation and obtain
time-dependent dark energy density. Then discuss Hubble expansion parameter and
scale factor and fix them by using observational data. We also investigate
stability of this theory
Corrections Terms for the Thermodynamics of a Black Saturn
In this paper, we will analyze the effects of thermal fluctuations on the
stability of a black Saturn. The entropy of the black Saturn will get corrected
due to these thermal fluctuations. We will demonstrate that the correction term
generated by these thermal fluctuations is a logarithmic term. Then we will use
this corrected value of the entropy to obtain bounds for various parameters of
the black Saturn. We will also analyze the thermodynamical stability of the
black Saturn in presence of thermal fluctuations, using this corrected value of
the entropy.Comment: 15 pages, revised version has been accepted for publication in Phys.
Lett.
Effect of Thermal Fluctuations on a Charged Dilatonic Black Saturn
In this paper, we will analyze the effect of thermal fluctuations on the
thermodynamics of a charged dilatonic black Saturn. These thermal fluctuations
will correct the thermodynamics of the charged dilatonic black Saturn. We will
analyze the corrections to the thermodynamics of this system by first relating
the fluctuations in the entropy to the fluctuations in the energy. Then, we
will use the relation between entropy and a conformal field theory to analyze
the fluctuations in the entropy. We will demonstrate that similar physical
results are obtained from both these approaches. We will also study the effect
of thermal fluctuations on the phase transition in this charged dilatonic black
Saturn
The lower bound violation of shear viscosity to entropy ratio due to logarithmic correction in STU model
In this paper, we analyze the effects of thermal fluctuations on a STU black
hole. We observe that these thermal fluctuations can affect the stability of a
STU black hole. We will also analyze the effects of these thermal fluctuations
on the thermodynamic of STU black hole. Furthermore, in the Jacobson formalism
such a modification will produce a deformation of the geometry of the STU black
hole. Hence, we use the AdS/CFT correspondence to analyze the effect of such a
deformation on the dual quark-gluon plasma. So, we explicitly analyze the
effect of thermal fluctuations on the shear viscosity to entropy ratio in the
quark-gluon plasma, and analyze the effects of thermal fluctuations on this
ratio
Exponential corrected thermodynamics of black holes
Recently, it is reported that thermal fluctuations which are interpreted as
quantum effects, modify black holes entropy by an exponential term. We now find
the effect of such modification on black hole mass and other thermodynamics
quantities. We find that Schwarzschild black hole mass decreased by thermal
fluctuations. Hence, we study exponential corrected thermodynamics and
statistics of black holes by computing the partition function. We obtain
special condition on the event horizon radius to satisfy Smarr-Gibbs-Duhem
relation in the presence of quantum correction. As we know the Schwarzschild
black hole is unstable, while the effect of exponential correction is the
stability of Schwarzschild black hole as well as the Schwarzschild-AdS
black hole at a small area. On the other hand, a Schwarzschild black hole
is completely unstable. The effect of quantum correction on the
Reissner-Nordstr\"{o}m black hole is instability at quantum scales. Finally, we
consider the most general case of charged AdS black hole and study corrected
thermodynamics.Comment: 19 pages, 15 figure
Testing Quantum Gravity through Dumb Holes
We propose a method to test the effects of quantum fluctuations on black
holes by analyzing the effects of thermal fluctuations on dumb holes, the
analogues for black holes. The proposal is based on the Jacobson formalism,
where the Einstein field equations are viewed as thermodynamical relations, and
so the quantum fluctuations are generated from the thermal fluctuations. It is
well known that all approaches to quantum gravity generate logarithmic
corrections to the entropy of a black hole and the coefficient of this term
varies according to the different approaches to the quantum gravity. It is
possible to demonstrate that such logarithmic terms are also generated from
thermal fluctuations in dumb holes. In this paper, we claim that it is possible
to experimentally test such corrections for dumb holes, and also obtain the
correct coefficient for them. This fact can then be used to predict the effects
of quantum fluctuations on realistic black holes, and so it can also be used,
in principle, to experimentally test the different approaches to quantum
gravity.Comment: Accepted for publication in Annals of Physic
Thermodynamics and phase transitions of galactic clustering in higher-order Modified Gravity
We study the thermodynamics of galactic clustering under the higher-order
corrected Newtonian dynamics. The clustering of galaxies is considered as a
gravitational phase transition. In order to study the effects of higher-order
correction to the thermodynamics of gravitational system, we compute more exact
equations of state. Moreover, we investigate the corrected probability
distribution function for such gravitating system. A relation between order
parameter and the critical temperature is also established.Comment: Accepted for publication in IJMP
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