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Results from a new series of experiments on turbulent flows in a rotating circular container are presented. Electromagnetic forcing is applied to induce flow in a layer of fluid of constant depth. Continuously forced as well as decaying…

Atmospheric and Oceanic Physics · Physics 2013-04-11 Y. D. Afanasyev , J. D. C. Craig

Vertical oscillation of a fluid interface above a critical amplitude excites the Faraday instability, typically manifesting itself as a standing wave pattern. Fundamentally, the phenomenon is an example of parametric resonance. At high…

Fluid Dynamics · Physics 2013-10-10 William Batson , Farzam Zoueshtiagh , Ranga Narayanan

We describe the design and performance of a new rotating dilution refrigerator that will primarily be used for investigating the dynamics of quantized vortices in superfluid 4He. All equipment required to operate the refrigerator and…

Instrumentation and Detectors · Physics 2013-10-09 M. J. Fear , P. M. Walmsley , D. A. Chorlton , D. E. Zmeev , S. J. Gillott , M. C. Sellers , P. P. Richardson , H. Agrawal , G. Batey , A. I. Golov

We report measurements of electric potentials at the surface of a spherical container of liquid sodium in which a magnetized inner core is differentially rotating. The azimuthal angular velocities inferred from these potentials reveal a…

We study the stability of standing shock waves in advection-dominated accretion flows into a Schwarzschild black hole by 2D general relativistic hydrodynamic simulations as well as linear analysis in the equatorial plane. We demonstrate…

Astrophysics · Physics 2009-11-13 Hiroki Nagakura , Shoichi Yamada

A perturbative analysis is used to investigate the effect of rotation on the instability of a steady accretion shock (SASI) in a simple toy-model, in view of better understanding supernova explosions in which the collapsing core contains…

Astrophysics · Physics 2009-11-13 Tatsuya Yamasaki , Thierry Foglizzo

This paper presents a study of acoustic scattering by a cylinder of either infinite or finite length near a flat pressure-release surface. A novel self-consistent method is developed to describe the multiple scattering interactions between…

Atmospheric and Oceanic Physics · Physics 2007-05-23 Zhen Ye , You-Yu Chen

Angular oscillations can provide a useful probe of the superfluid properties of a system. Such measurements have recently been applied to dipolar supersolids, which exhibit both density modulation and phase coherence, and for which robust…

We consider a cylindrical film of fluid adhering to a rigid cylinder of fixed radius. The main result is to give the critical (maximum) length for which such a film of given thickness can be stable. The problem is considered both when the…

Analysis of PDEs · Mathematics 2016-09-07 John McCuan

Vortex dynamics in superfluids is investigated in the framework of the nonlinear Schr\"{o}dinger equation. The natural motion of the vortex is of cyclotron type, whose frequency is found to be on the order of phonon velocity divided by the…

Condensed Matter · Physics 2009-10-28 E. Demircan , P. Ao , Q. Niu

Differential rotation occurs in conducting flows in accretion disks and planetary cores. In such systems, the magnetorotational instability can arise from coupling Lorentz and centrifugal forces to cause large radial angular momentum…

We study the stability of odd-dimensional rotating black holes with equal angular momenta by performing an expansion in the inverse of the number of dimensions D. Universality at large $D$ allows us to calculate analytically the complex…

High Energy Physics - Theory · Physics 2022-03-07 Roberto Emparan , Ryotaku Suzuki , Kentaro Tanabe

Plane inertial waves are generated using a wavemaker, made of oscillating stacked plates, in a rotating water tank. Using particle image velocimetry, we observe that, after a transient, the primary plane wave is subject to a subharmonic…

Fluid Dynamics · Physics 2012-05-22 Guilhem Bordes , Frédéric Moisy , Thierry Dauxois , Pierre-Philippe Cortet

We investigate the conditions for the emergence of wave instabilities in a vacuum cavity delimited by cylindrical metallic walls under rotation. It is shown that for a small vacuum gap and for an angular velocity exceeding a certain…

Optics · Physics 2016-09-14 Sylvain Lannebère , Mário G. Silveirinha

Rotational superradiance affects the dynamics of many rotating systems in nature, through either stimulated or spontaneous extraction of energy and angular momentum. By now, this process is well-studied in the relativistic setting, where…

General Relativity and Quantum Cosmology · Physics 2021-06-09 Sam Patrick

We present the theoretical prediction of spontaneous rotating vortex rings in a parametrically driven quantum fluid of polaritons -- coherent superpositions of coupled quantum well excitons and microcavity photons. These rings arise not…

Quantum Gases · Physics 2016-06-29 J. O. Hamp , A. K. Balin , F. M. Marchetti , D. Sanvitto , M. H. Szymanska

Electron-phonon interaction is of central importance for the electrical and heat transport properties of metals, and is directly responsible for charge-density-waves or (conventional) superconducting instabilities. The direct observation of…

Superconductivity · Physics 2022-02-02 S. M. Souliou , A. Bosak , G. Garbarino , M. Le Tacon

This article starts by providing an introductory overview of the theoretical mechanics of rotating neutron stars as developped to account for the frequency variations, and particularly the discontinuous glitches, observed in pulsars. The…

Astrophysics · Physics 2007-05-23 Brandon Carter

Strong-field gravity simulators are laboratory experiments that can investigate a wide range of both classical and quantum phenomena occurring in nature. In this work, we introduce an effective geometry that captures most of the…

General Relativity and Quantum Cosmology · Physics 2025-05-12 H. S. Vieira , Kyriakos Destounis , Kostas D. Kokkotas

Focusing on the rotating black hole (BH) surrounded by the anisotropic fluid matters; radiation, dust, and dark matter, we study the massive scalar superradiant scattering and the stability in the Kiselev spacetime. Superradiance behavior…

General Relativity and Quantum Cosmology · Physics 2021-11-16 Mohsen Khodadi , Reza Pourkhodabakhshi