Related papers: Boson Star Superradiance
We discuss various scattering properties of non-topological solitons, Q-balls, on potential obstructions in (1+1) and (2+1) dimensions. These obstructions, barriers and holes, are inserted into the potential of the theory via the coupling…
Rotational excitations of compact Q-balls in the complex signum-Gordon model in 2+1 dimensions are investigated. We find that almost all such spinning Q-balls have the form of a ring of strictly finite width. In the limit of large angular…
A two-dimensional dilatonic black hole induced by a topological soliton is exactly solvable in the scalar field theory coupled to dilaton gravity. The Hawking radiation of the black hole is studied in the one-loop approximation with the…
Magneto-elastic oscillations of neutron stars are believed to explain observed quasi-periodic oscillations (QPOs) in the decaying tail of the giant flares of highly magnetized neutron stars (magnetars). Strong efforts of the theoretical…
Magnetohydrodynamic star-in-a-box simulations of convection and dynamos in a solar-like star with different rotation rates are presented. These simulations produce solar-like differential rotation with a fast equator and slow poles, and…
We investigate the absorption and scattering of charged massive scalar waves by the Kerr-Newman black-bounce spacetime when the waves are incident along the rotation axis. Our findings indicate that a faster (slower) rotating spacetime or a…
The properties of several types of Q-stars are studied and compared with their flat space analogues, i.e. Q-balls. The analysis is based on calculating the mass, global U(1) charge and binding energy for families of solutions parametrized…
In this work, we study the time evolution of radial kinks in the background of boson stars. In particular, we consider two types of boson stars: the massive boson star and the solitonic boson star. For each boson star, we study the dynamics…
We construct hydromagnetic neutron star equilibria which allow for a non-zero electric current distribution in the exterior. The novelty of our models is that the neutron star's interior field is in equilibrium with its magnetosphere, thus…
Solitons propagating in media with higher order dispersion will shed radiation known as dispersive wave or resonant radiation, with applications in frequency broadening, deep UV sources for spectroscopy or simply fundamental studies of…
We examine the possibility of rolling tachyon to play the dual roll of inflaton at early epochs and dark matter at late times. We argue that enough inflation can be generated with the rolling tachyon either by invoking the large number of…
Diffusion in cool B stars of the main sequence has been shown to strongly affect opacities and convection in cool B stars of the main sequence. We show here that diffusion in B stars maintains or enhances the excitation of pulsations in…
Rotating black holes can form dense boson clouds through superradiant instability, making Kerr black holes a powerful probe of ultralight massive bosons. Previous studies of black hole superradiance have often treated bosonic fields…
We study effects of the strange quark mass and of the QCD coupling constant in the MIT bag model of quark matter with lowest order quark-gluon interactions on the rapid rotation of strange stars. The influence of rotation on global…
Supersymmetry predicts multiple flat directions, some of which carry a net baryon or lepton number. Condensates in such directions form during inflation and later fragment into Q-balls, which can become the building blocks of primordial…
Complex scalar fields charged under a global U(1) symmetry can admit non-topological soliton configurations called Q-balls which are stable against decay into individual particles or smaller Q-balls. These Q-balls are interesting objects…
We review recent results of stellar pulsation modelling that show that even very simple one-dimensional models for time dependent turbulent energy diffusion and convection provide a substantial improvement over purely radiative models.
Superradiance of nuclear spins is considered, when the nuclei interact via hyperfine forces with electrons of a ferromagnet. The consideration is based on a microscopic model. If the sample, coupled with a resonant electric circuit,…
We study the superradiant scattering of gravitational waves by a nearly extremal black hole (dimensionless spin $a=0.99$) by numerically solving the full Einstein field equations, thus including backreaction effects. This allows us to study…
Theories with low-energy supersymmetry predict the existence of stable non-topological solitons, Q-balls, that can contribute to dark matter. We discuss the experimental signatures, methods of detection, and the present limits on such dark…