Lamb Shift for static atoms outside a Schwarzschild black hole

Abstract

We study, by separately calculating the contributions of vacuum fluctuations and radiation reaction to the atomic energy level shift, the Lamb shift of a static two-level atom interacting with real massless scalar fields in the Boulware, Unruh and Hartle-Hawking vacuums outside a Schwarzschild black hole. We find that in the Boulware vacuum, the Lamb shift gets a correction arising as a result of the backscattering of vacuum field modes off the space-time curvature, which is reminiscent of the correction to the Lamb shift induced by the presence of cavities. However, when the Unruh and Hartle-Hawking vacua are concerned, our results show that the Lamb shift behaves as if the atom were irradiated by a thermal radiation or immersed in a thermal bath at the Hawking temperature, depending on whether the scalar field is in the Unruh or the Hartle-Hawking vacuum. Remarkably, the thermal radiation is always backscattered by the space-time geometry.

14 pages, no figures, to be published in PRD

References in corpus (6)

• Spontaneous excitation of an accelerated atom: The contributions of vacuum fluctuations and radiation reaction
• Radiative energy shifts of accelerated atoms
• The Unruh effect and entanglement generation for accelerated atoms near a reflecting boundary
• Position dependent energy level shifts of an accelerated atom in the presence of a boundary
• Do static atoms outside a Schwarzschild black hole spontaneously excite?
• Relationship between Hawking radiation from black holes and spontaneous excitation of atoms

Cited by in corpus (13)

• Thermal and non-thermal signatures of the Unruh effect in Casimir-Polder forces
• Spontaneous excitation of a uniformly accelerated atom coupled with vacuum Dirac field fluctuations
• Geometric phase of two-level atoms and thermal nature of de Sitter spacetime
• Entanglement generation outside a Schwarzschild black hole and the Hawking effect
• The Lamb shift in de Sitter spacetime
• Detecting the Curvature of de Sitter Universe with Two Entangled Atoms
• Boundarylike behaviors of the resonance interatomic energy in a cosmic string spacetime
• Spontaneous excitation of an accelerated atom coupled with quantum fluctuations of spacetime
• Lamb shift as a witness for quantum noninertial effects
• Can spacetime curvature induced corrections to Lamb shift be observable?
• Dynamics of an elementary quantum system outside a radiating Schwarzschild black hole
• Atom-field dynamics in curved spacetime
• The Lamb shift in the BTZ spacetime