Related papers: Absorption of fixed scalars
We study the emission of scalar particles from a class of near-extremal five dimensional black holes and the corresponding D-brane configuration at high energies. We show that the distribution functions and the black hole greybody factors…
We discuss the role of fixed scalars($\nu,\lambda$) in scattering off a five-dimensional balck hole. The issue is to explain the disagreement of the greybody factor for $\lambda$ between the semiclassical and effective string calculations.…
It has recently been shown that the equation of motion of a massless scalar field in the background of some specific p branes can be reduced to a modified Mathieu equation. In the following the absorption rate of the scalar by a D3 brane in…
We explore the interplay between black holes in supergravity and quantum field theories on the world-volumes of D-branes. A brief summary of black hole entropy calculations for D-brane black holes is followed by a detailed study of particle…
We compute the spectrum of quasinormal frequencies of five-dimensional black holes obtained in noncommutative geometry. In particular, we study scalar perturbations of a massive scalar field adopting the 6th order WKB approximation. We…
We discuss the phenomenology of massless scalar fields around a regular Bardeen black hole, namely absorption cross section, scattering cross section and quasinormal modes. We compare the Bardeen and Reissner-Nordstr\"om black holes,…
The semi-classical cross-sections for arbitrary partial waves of ordinary scalars to fall into certain five-dimensional black holes have a form that seems capable of explanation in terms of the effective string model. The kinematics of…
For minimally coupled scalars at low frequencies, the D-brane model has the same spectrum of radiation as the Hawking radiation from a black hole. We perform a similar comparison for another type of scalar which we call an intermediate…
We calculate the one loop effective action for D-brane probes moving in the presence of near BPS D-branes. The $v^2$ term agrees with supergravity in all cases and the static force agrees for a five dimensional black hole with two large…
We construct the non-extreme solutions of non-orthogonal intersecting D-branes. The solutions reduce to non-extreme black holes upon the toroidal compactification. We clarify the relation between two configurations with equal mass and…
We study the emission of scalars into the bulk from a higher-dimensional rotating black hole. We obtain an analytic solution to the field equation by employing matching techniques on expressions valid in the near-horizon and far-field…
The absorption rate of low-energy, or soft, electromagnetic radiation by spherically symmetric black holes in arbitrary dimensions is shown to be fixed by conservation of energy and large gauge transformations. We interpret this result as…
We calculate the absorption probabilities for a class of massless fields whose linear perturbations leave the near-extremal D3-brane background metric unperturbed. It has previously been found that, for extremal D3-branes, these fields…
We investigate the absorption of a massive and charged scalar field in a Reissner-Nordstr\"om background. We compare our numerical results for the absorption cross section, obtained for arbitrary frequencies, with the low- and…
Accurate and powerful computational methods developed by the author for the wave scattering by black holes allow to obtain the highly non trivial total absorption spectrum of the Black Hole. As well as partial wave phase shifts and cross…
We study the absorption of a class of fields in the geometry produced by extremal three-branes. We consider fields that do not mix with the ten-dimensional graviton. For these fields we solve the wave equations and find the absorption…
We consider five-dimensional black holes modeled by D-strings bound to D5-branes, with momentum along the D-strings. We study the greybody factors for the non-minimally coupled scalars which originate from the gravitons and R-R…
We review the timelike dimensional reduction of a class of five-dimensional theories that generalises 5D, N = 2 supergravity coupled to vector multiplets. As an application we construct instanton solutions to the four-dimensional Euclidean…
Recently Das and Mathur found that the leading order Hawking emission rate of neutral scalars by near-extremal $D=5$ black holes is exactly reproduced by a string theoretic model involving intersecting D-branes. We show that the agreement…
Black holes are a paradigm in nowadays physics, and are expected to be hosted at the center of galaxies. Supermassive galactic black holes are not isolated, and their surroundings play crucial roles in many observational features. The…