arXiv subjects

Nisha Jangid

Publications and source records attributed to Nisha Jangid.

2 recordsLinked to original sources

arXiv2026

Acoustic Hawking radiation as a tunnelling effect in Michel accretion

Michel accretion becomes transonic at the saddle point of a dynamical system. An Eulerian perturbation on the steady inflow produces the metric of an acoustic black hole. As a high-frequency travelling wave the perturbation does not destabilize the steady inflow. Acoustic waves propagating outwards against the fluid inflow are blocked at the sonic barrier but can tunnel through it with an exponentially decaying amplitude. The Hawking temperature and the frequency of the Hawking phonons are enhanced by the spacetime geometry.

gr-qc↗

arXiv2025

Penetrating the horizon of a hydrodynamic white hole

In a shallow-water radial outflow the horizon of a hydrodynamic white hole coincides with a standing circular hydraulic jump. The jump, caused by viscosity, makes the horizon visible as a circular front, standing as a barrier against the entry of waves within its circumference. The blocking of waves causes a pile-up at the horizon of the white hole, for which surface tension is mainly responsible. Conversely, it is also because of surface tension that the waves can penetrate the barrier. The penetrating waves (analogue Hawking quanta) tunnel through the barrier with a decaying amplitude, but a large-amplitude instability about the horizon is possible.

gr-qc↗