Yusuf Sucu

Exact solution of Dirac equation in 2+1 dimensional gravity

We find exact solutions of the Dirac equation in the 2+1 dimensional curved background by separation of variables. These solutions are given in terms of hypergeometric functions. We also perform the Gordon decomposition for the Dirac current to discuss the time dependence of the polarization densities and the magnetization density, and to show that the polarization densities are more effective than the magnetization density in the pair production in finite time intervals.

Dirac equation in Euclidean Newman–Penrose formalism with applications to instanton metrics

We derive the Dirac equation in the Euclidean version of the Newman–Penrose formalism and show that it splits into two sets of equations, particle and anti-particle equations, under the swapping symmetry and these equations are coupled, respectively, with the self-dual and anti-self-dual parts of the gauge in the gravity. We also solve it for Eguchi–Hanson and Bianchi VII0 gravitational instanton metrics. The solutions are obtained for the Bianchi VII0 gravitational instanton metric as exponential functions by using complex variable ξ and for the Eguchi–Hanson gravitational instanton metric as the product of two hypergeometric functions. In addition, we discuss the regularity and the swapping symmetry of the solutions and show that the topological index of the Dirac equation is zero for both of these metrics.

Tunnelling of relativistic particles from new type black hole in new massive gravity

In the framework of the three dimensional New Massive Gravity theory introduced by Bergshoeff, Hohm and Townsend, we analyze the behavior of relativistic spin-1/2 and spin-0 particles in the New-type Black Hole backgroud, solution of the New Massive Gravity.We solve Dirac equation for spin-1/2 and Klein-Gordon equation for spin-0. Using Hamilton-Jacobi method, we discuss tunnelling probability and Hawking temperature of the spin-1/2 and spin-0 particles for the black hole. We observe that the tunnelling probability and Hawking temperature are same for the spin-1/2 and spin-0.

Noether Gauge Symmetry of Dirac Field in (2 + 1)-Dimensional Gravity

We consider a gravitational theory including a Dirac field that is nonminimally coupled to gravity in 2 + 1 dimensions. Noether gauge symmetry approach can be used to fix the form of coupling function and the potential of the Dirac field and to obtain a constant of motion for the dynamical equations. In the context of (2 + 1)-dimensional gravity, we investigate cosmological solutions of the field equations using these forms obtained by the existence of Noether gauge symmetry. In this picture, it is shown that, for the nonminimal coupling case, the cosmological solutions indicate both an early-time inflation and late-time acceleration for the universe.

Solution of Massless Spin One Wave Equation in Robertson-Walker Space-time

We generalize the quantum spinor wave equation for photon into the curved space–time and discuss the solutions of this equation in Robertson–Walker space–time and compare them with the solution of the Maxwell equations in the same space–time.

The GUP effect on Hawking radiation of the 2 + 1 dimensional black hole

Abstract We investigate the Generalized Uncertainty Principle (GUP) effect on the Hawking radiation of the 2 + 1 dimensional Martinez–Zanelli black hole by using the Hamilton–Jacobi method. In this connection, we discuss the tunneling probabilities and Hawking temperature of the spin-1/2 and spin-0 particles for the black hole. Therefore, we use the modified Klein–Gordon and Dirac equations based on the GUP. Then, we observe that the Hawking temperature of the scalar and Dirac particles depend on not only the black hole properties, but also the properties of the tunneling particle, such as angular momentum, energy and mass. And, in this situation, we see that the tunneling probability and the Hawking radiation of the Dirac particle is different from that of the scalar particle.

Dirac Field as a Source of the Inflation in Dimensional Teleparallel Gravity

In this paper, we study early-time inflation and late-time acceleration of the universe by nonminimally coupling the Dirac field with torsion in the spatially flat Friedman-Robertson-Walker (FRW) cosmological model background. The results obtained by the Noether symmetry approach with and without a gauge term are compared. Additionally, we compare these results with that of the dimensional teleparallel gravity under Noether symmetry approach. And we see that the study explains early-time inflation and late-time acceleration of the universe.

Quantum Gravity Effect on the Tunneling Particles from 2 + 1-Dimensional New-Type Black Hole

We investigate the Generalized Uncertainty Principle (GUP) effect on the Hawking temperature for the 2+1 dimensional New-type black hole by using the quantum tunneling method for both the spin-1/2 Dirac and the spin-0 scalar particles. In computation of the GUP correction for the Hawking temperature of the black hole, we modified Dirac and Klein-Gordon equations. We observed that the modified Hawking temperature of the black hole depends not only on the black hole properties, but also on the graviton mass and the intrinsic properties of the tunneling particle, such as total angular momentum, energy and mass. Also, we see that the Hawking temperature was found to be probed by these particles in different manners. The modified Hawking temperature for the scalar particle seems to be lower compared to its standard Hawking temperature. Also, we find that the modified Hawking temperature of the black hole caused by Dirac particles tunnelling rised by the total angular momentum of the particle. It is diminishable by the energy and mass of the particle and graviton mass as well. These intrinsic properties of the particle, except total angular momentum for the Dirac particle, and graviton mass may cause screening for the black hole radiation.

The GUP Effect on Tunneling of Massive Vector Bosons from The 2

In this study, the Generalized Uncertainty Principle (GUP) effect on the Hawking radiation formed by tunneling of a massive vector boson particle from the 2+1 dimensional new-type black hole was investigated. We used modified massive vector boson equation based on the GUP. Then, the Hamilton-Jacobi quantum tunneling approach was used to work out the tunneling probability of the massive vector boson particle and Hawking temperature of the black hole. Due to the GUP effect, the modified Hawking temperature was found to depend on the black hole properties, on the AdS3 radius, and on the energy, mass, and total angular momentum of the tunneling massive vector boson. In the light of these results, we also observed that modified Hawking temperature increases by the total angular momentum of the particle while it decreases by the energy and mass of the particle and the graviton mass. Also, in the context of the GUP, we see that the Hawking temperature due to the tunneling massive vector boson is completely different from both that of the spin-0 scalar and that of the spin-1/2 Dirac particles obtained in the previous study. We also calculate the heat capacity of the black hole using the modified Hawking temperature and then discuss influence of the GUP on the stability of the black hole.

Quantum gravity effect on the tunneling particles from Warped-AdS3 black hole

In this study, using the Hamilton–Jacobi approach, we investigated the Hawking temperature of the (2 + 1)-dimensional Warped-AdS3 black hole by considering the generalized uncertainty principle (GU...