Superradiance in a ghost-free scalar theory

Abstract

We study superradiance effect in the ghost-free theory. We consider a scattering of a ghost-free scalar massless field on a rotating cylinder. We assume that cylinder is thin and empty inside, so that its interaction with the field is described by a delta-like potential. This potential besides the real factor, describing its height, contains also imaginary part, responsible for the absorption of the field. By calculating the scattering amplitude we obtained the amplification coefficient both in the local and non-local (ghost-free) models and demonstrated that in the both cases it is greater than 1 when the standard superradiance condition is satisfied. We also demonstrated that dependence of the amplification coefficient on the frequency of the scalar field wave may be essentially modified in the non-local case.

arXiv comment11 pages, 5 figures

References in corpus (20)

• Observation of superradiance in a vortex flow
• The many faces of superradiance
• Mass-gap for black hole formation in higher derivative and ghost free gravity
• Classical properties of non-local, ghost- and singularity-free gravity
• Ghost-free infinite derivative quantum field theory
• Head-on collision of ultrarelativistic particles in ghost-free theories of gravity
• Renormalization group in super-renormalizable quantum gravity
• Generalised superradiant scattering
• Do massive compact objects without event horizon exist in infinite derivative gravity?
• Superradiance in stars
• Detecting Rotational Superradiance in Fluid Laboratories
• Exact solutions and spacetime singularities in nonlocal gravity
• The Penrose process, superradiance and ergoregion instabilities
• Stability of Schwarzschild singularity in non-local gravity
• Rotating metric in Non-Singular Infinite Derivative Theories of Gravity
• Radiation from an emitter in the ghost free scalar theory
• Quantum scattering on a delta potential in ghost-free theory
• Universality of the Unruh effect
• Lorentz Invariance of Absorption and Extinction Cross Sections of a Uniformly Moving Object
• Comparison between two models of absorption of matter waves by a thin time-dependent barrier

Cited by in corpus (5)

• Ghost-free modification of the Polyakov action and Hawking radiation
• Superradiant energy extraction from rotating hairy Horndeski black holes
• Superradiance and quasinormal modes of the gravitational perturbation around rotating hairy black hole
• Scalar Perturbation Around Rotating Regular Black Hole: Superradiance Instability and Quasinormal Modes
• Nonlocal scalar field in an external potential: WKB approximation