A Very Effective String Model?

TL;DR

This paper provides evidence supporting an effective string model for 5D black holes, demonstrating that the model accurately predicts low-energy scattering absorption, with implications for understanding Hawking radiation back reaction.

Contribution

It offers new evidence that the effective string model accurately describes 5D black hole physics, including scattering and emission processes, and discusses its potential implications for Hawking radiation.

Findings

Computed the low energy absorption coefficient for scalar scattering.

Conjectured an exact form for the absorption coefficient based on the model.

Found that the model's predictions match the scattering data, supporting its validity.

Abstract

Additional evidence is presented for a recently proposed effective string model, conjectured to hold throughout the parameter space of the basic 5 dimensional, triply charged black holes, which includes the effects of brane excitations, as well as momentum modes. We compute the low energy spacetime absorption coefficient $\sigma$ for the scattering of a triply-charged scalar field in the near extremal case, and conjecture an exact form for $\sigma$. It is shown that this form of $\sigma$ arises simply from the effective string model. This agreement encompasses both statistical factors coming from the Bose distributions of string excitations and a prefactor which depends on the effective string radius. An interesting feature of the effective string model is that the change in mass of the effective string system in an emission process is not equal to the change in the energies of the effective string excitations. If the model is valid, this may hold clues towards understanding back reaction due to Hawking radiation. A number of weak spots and open questions regarding the model are also noted.