Equation Of State Functions Research Articles

Thermodynamics and Shadows of quantum-corrected Reissner–Nordström black hole surrounded by quintessence

In this work, we consider the quantum-corrected Reissner–Nordström black hole surrounded by quintessence matter and examine its thermodynamics and shadow. To this end, we handle the quantum-corrected metric of the black hole, which is given by Wu and Lui in 2022, and couple the quintessence matter field effects to the lapse function. Then, we obtain the mass, Hawking temperature, specific heat, and equation of state functions. In all these functions, we discuss two cases in which the quantum corrections are greater or smaller than the quintessence matter effects. We observe that within these two scenarios, the black hole has different characteristic thermal behaviors. Moreover, we find that the quintessence matter plays an important role in leading to a black hole remnant. Furthermore, we observe that black hole behaves like Van der Waals fluid. Finally, we investigate the black hole shadow by Carter’s approach. We find that quintessence matter and quantum corrections modify the shadow of the black hole.

Thermodynamics of Schwarzschild black hole surrounded by quintessence in gravity's rainbow

According to some quantum gravity models, Lorentz invariance can be violated in the Planck energy scale. With this motivation, we analyze the thermal quantities and the stability of Schwarzschild black hole surrounded by quintessence in gravity's rainbow formalism. To do that, we consider the rainbow functions which are motivated by loop quantum gravity and gamma-ray bursts, and we derive Hawking temperature, specific heat, entropy and the equation of state function. We observe that the presence the quintessence matter field and rainbow gravity affect the stability of the black hole.

Thermodynamics of Schwarzschild black hole surrounded by quintessence with generalized uncertainty principle

In this manuscript, we consider a deformation on the Heisenberg algebra and investigate the effects on the thermodynamics of the Schwarzschild black hole that is surrounded by quintessence matter. To this end, we obtain the temperature, entropy and heat capacity functions of the black hole by using the standard laws of thermodynamic according to the considered deformation. We show that upper and lower bound values appear on these functions based on the quintessence and deformed algebra. Then, we derive the corrected density of quintessence matter and the black hole’s equation of state functions. We compare these results with the standard Schwarzschild black hole with and without quintessence with the graphical methods and interpret the quantum deformation effects.

Role of equation of states and thermodynamic potentials in avoidance of trapped surfaces in gravitational collapse

In this paper we consider the novel scenario where a spherically symmetric perfect fluid star is undergoing continual gravitational collapse while continuously radiating energy in an exterior radiating spacetime. There are no trapped surfaces and the collapse ends to a flat spacetime. Also the collapsing matter obeys the weak and dominant energy conditions at all epoch. Our analysis transparently brings out the role of the equation of state as well as the bounds on the thermodynamic potentials to realise such a scenario. We argue that, since the system of Einstein field equations allows for such a scenario for an open set of initial data as well as the equation of state function in their respective functional spaces, these models are generic and devoid of the problems and paradoxes related to horizons and singularities. The recent high resolution radio telescopes should in principle detect the presence of these compact objects in the sky.

Improved modified embedded-atom method potentials for gold and silicon

The modified embedded-atom method interatomic potentials for pure gold and pure silicon are improved in their melting point and latent heat predictions, by modifying the multi-body screening function and the equation of state function. The fitting of the new parameters requires rapid calculations of melting point and latent heat, which are enabled by efficient free-energy methods. The results provide the basis for constructing a cross-potential that will be fitted to the binary gold–silicon phase diagram.