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Geometrothermodynamics: comments, criticisms, and support
(2014)
We write explicitly the Euler identity and the Gibbs-Duhem relation for thermodynamic potentials that are not homogeneous first-order functions of their natural extensive variables. We apply the rules to the theory of ...
Regular and conformal regular cores for static and rotating solutions
(2014)
Using a new metric for generating rotating solutions, we derive in a general fashion the solution of an imperfect fluid and that of its conformal homolog. We discuss the conditions that the stress-energy tensors and invariant ...
From static to rotating to conformal static solutions: rotating imperfect fluid wormholes with(out) electric or magnetic field
(2014)
We derive a shortcut stationary metric formula for generating imperfect fluid rotating solutions, in Boyer-Lindquist coordinates, from spherically symmetric static ones. We explore the properties of the curvature scalar ...
On 'rotating charged AdS solutions in quadratic f(T) gravity': new rotating solutions
(2020)
We show that there are two or more procedures to generalize the known four-dimensional transformation, aiming to generate cylindrically rotating charged exact solutions, to higher dimensional spacetimes. In the one procedure, ...
Charged de Sitter-like black holes: quintessence-dependent enthalpy and new extreme solutions
(2015)
We consider Reissner-Nordstrom black holes surrounded by quintessence where both a non-extremal event horizon and a cosmological horizon exist besides an inner horizon (-1 = omega < - 1/3). We determine new extreme black ...
Wormhole solutions sourced by fluids, I: Two-fluid charged sources
(2016)
We briefly discuss some of the known and new properties of rotating geometries that are relevant to this work. We generalize the analytical method of superposition of fields, known for generating nonrotating solutions, and ...
Wormhole solutions sourced by fluids, II: three-fluid two-charged sources
(2016)
Lack of a consistent metric for generating rotating wormholes motivates us to present a new one endowed with interesting physical and geometrical properties. When combined with the generalized method of superposition of ...
Cyclic and heteroclinic flows near general static spherically symmetric black holes
(2016)
We investigate the Michel-type accretion onto a static spherically symmetric black hole. Using a Hamiltonian dynamical approach, we show that the standard method employed for tackling the accretion problem has masked some ...
Astrophysical flows near f (T) gravity black holes
(2016)
In this paper, we study the accretion process for fluids flowing near a black hole in the context of f (T) teleparallel gravity. Specifically, by performing a dynamical analysis by a Hamiltonian system, we are able to find ...
Shadow, quasinormal modes, and quasiperiodic oscillations of rotating Kaluza-Klein black holes
(2020)
In this paper we study the shadow of rotating Kaluza-Klein (KK) black holes and the connection between the shadow radius and the real part of quasinormal modes (QNMs) in the eiokonal limit. In addition we have explored the ...