Thermal Radiation of Various Gravitational Backgrounds

Abstract

We present a simple and general procedure for calculating the thermal radiation coming from any stationary metric. The physical picture is that the radiation arises as the quasi-classical tunneling of particles through a gravitational barrier. We study three cases in detail: the linear accelerating observer (Unruh radiation), the non-rotating black hole (Hawking radiation), and the rotating/orbiting observer (circular Unruh radiation). For the linear accelerating observer we obtain a thermal spectrum with the usual Unruh temperature. For the non-rotating black hole we obtain a thermal spectrum, but with a temperature twice that given by the original Hawking calculations. We discuss possible reasons for the discrepancies in temperatures as given by the two different methods. For the rotating/orbiting case the quasi-classical tunneling approach indicates that there is no thermal radiation. This result for the rotating/orbiting case has experimental implications for the experimental detection of this effect via the polarization of particles in storage rings.

Charged Particle’s Tunneling in a Modified Reissner-Nordstrom Black Hole

“…Further, some resent progress and insights for the tunneling program have been proposed [19][20][21][22][44][45][46][47][48][49][50][51][52][53][54]. Therein, with the aid of density matrix techniques, the tunneling mechanism was reformulated to directly find the radiation spectrum [44,45] and the approach was applied in different gravity to obtain the entropy spectrum of black holes [46].…”

“…It is noteworthy that, by this approach, the black body spectrum was obtained [21,22,44,45]. In addition, some proposals on the calculation of particle's action and the acquisition of black hole information have been proposed [47][48][49][50][51][52][53][54]. But, in the literatures, much less attention was paid to the case of charged particle's tunneling in the quantum corrected spacetime [42].…”

Hawking Radiation of Scalar and Vector Particles from 5D Myers-Perry Black Holes

“…In order to calculate the tunneling rate, one faces the well known factor-two problem (see for example [39,40]). The right way to solve this problem is to consider first the invariance under canonical transformations given as p r dr = p + r dr − p − r dr. We can first calculate the spatial contribution of the imaginary part of Im R(r).…”

“…According to Akhmedova et al [39], we can find the resulting tunneling rate by putting all these results together…”

Quantum tunneling from a high dimensional Gödel black hole

“…[51][52][53][54][55], the expression of the tunneling rate Γ ∝ exp −Im P dr , instead of Γ ∝ exp −2Im P dr is invariant under canonical transformations. So the fermion's tunneling rate of the five-dimensional Gödel black hole can be written as…”