Related papers: Euclidean Dilaton Black Hole Vortex and Dirac Ferm…
The most general two-dimensional dilaton gravity theory coupled to an Abelian gauge field is considered. It is shown that, up to spacetime diffeomorphisms and $U(1)$ gauge transformations, the field equations admit a two-parameter family of…
Recently, the anomalous decay rate of quasinormal modes has been studied for some geometries under scalar field perturbations, which occurs when the longest-lived modes are the ones with higher angular number, as well as, the existence of a…
In this work we construct and analyse non-perturbative stationary and axially-symmetric black hole solutions in General Relativity coupled to an electromagnetic and an axion field. The axion field is coupled to the electromagnetic field,…
The standard Hawking formula predicts the complete evaporation of black holes. Taking into account effects of quantum gravity, we investigate fermions' tunnelling from a 5-dimensional rotating black string. The temperature is determined not…
Twisted Abelian gauge theory coupled to a noncommutative (NC) Dirac field is studied in order to infer the quasinormal mode (QNM) spectrum of the fermion matter perturbations in the vicinity of the Reissner-Nordstr\"om (RN) black hole. The…
In this paper we investigate the perturbations by a massless Dirac spinor of a Born-Infeld black hole. The decay rates of the spinor field which is given by the quasinormal mode frequencies are computed using the sixth order WKB…
Campbell et al. demonstrated the existence of axion ``hair'' for Kerr black holes due to the non-trivial Lorentz Chern-Simons term and calculated it explicitly for the case of slow rotation. Here we consider the dilaton coupling to the…
We consider stationary rotating black holes in SU(2) Einstein-Yang-Mills theory, coupled to a dilaton. The black holes possess non-trivial non-Abelian electric and magnetic fields outside their regular event horizon. While generic solutions…
In the background of a charged AdS black hole, we consider a Dirac particle endowed with an arbitrary magnetic dipole moment. For non-zero charge and dipole coupling of the bulk fermion, we find that the dual boundary theory can be plagued…
Black holes have a unique sensitivity to the presence of ultralight matter fields or modifications of the underlying theory of gravity. In the present paper we combine both features by studying an ultralight, dynamical scalar field that is…
Dirac cloud is in absence in general relativity since the superradiance mechanism fails to work for Dirac fields. For the first time we find a novel mechanism to support Dirac clouds, which is independent on superradiance mechanism. We…
Recently the modified Dirac equation with Lorentz invariance violation has been proposed, which would be helpful to resolve some issues in quantum gravity theory and high energy physics. In this paper, the modified Dirac equation has been…
The dislocation in Dirac semimetal carries an emergent magnetic flux parallel to the dislocation axis. We show that due to the emergent magnetic field the dislocation accommodates a single fermion massless mode of the corresponding…
We study Hawking radiation as a phenomenon of tunneling through event horizons of charged torus-like as well as dilaton black holes involving cosmological constant based on Kerner and Mann's formulation. We obtain tunneling probabilities as…
The intermediate and late-time behaviour of massive Dirac hair in the static spherically symmetric black hole spacetime was studied. It was revealed that the intermediate asymptotic pattern of decay of massive Dirac spinor hair is dependent…
We give analytical arguments and demonstrate numerically the existence of black hole solutions of the $4D$ Effective Superstring Action in the presence of Gauss-Bonnet quadratic curvature terms. The solutions possess non-trivial dilaton…
We investigate gravitational collapses of charged black holes in string-inspired gravity models, including dilaton gravity and braneworld model, as well as f(R) gravity and the ghost limit. If we turn on gauge coupling, the causal…
We consider black hole solutions with a dilaton field possessing a nontrivial potential approaching a constant negative value at infinity. The asymptotic behaviour of the dilaton field is assumed to be slower than that of a localized…
The role of the (dynamical) dilaton in the vortices associated with the spontaneous breaking of an anomalous U(1) from heterotic string theory is examined. We demonstrate how the anomaly (and the coupling to the dilaton/axion) can appear in…
In this work we study both charged and uncharged particles tunneling across the horizon of spherically symmetric dilaton-axion black holes using Parikh-Wilczek tunneling formalism. Such black hole solutions have much significance in string…