Acceleration radiation of an atom freely falling into a Kerr black hole and near-horizon conformal quantum mechanics

TL;DR

This paper demonstrates that an atom freely falling into a Kerr black hole emits thermal radiation due to acceleration effects near the horizon, with properties explained by near-horizon conformal quantum mechanics.

Contribution

It reveals the universal conformal behavior of acceleration radiation for all fields near black hole horizons, linking it to near-horizon conformal quantum mechanics.

Findings

Falling atoms emit Hawking-temperature radiation.

Radiation remains thermal for a cloud of atoms with random initial times.

The effect is governed by conformal quantum mechanics near the horizon.

Abstract

An atom falling freely into a Kerr black hole in a Boulware-like vacuum is shown to emit radiation with a Planck spectrum at the Hawking temperature. For a cloud of falling atoms with random initial times, the radiation is thermal. The existence of this radiation is due to the acceleration of the vacuum field modes with respect to the falling atom. Its properties can be traced to the dominant role of conformal quantum mechanics (CQM) in the neighborhood of the event horizon. We display this effect for a scalar field, though the acceleration radiation has a universal conformal behavior that is exhibited by all fields in the background of generic black holes.