235 citations · 1.8k across the 36 of their papers we have counts for
7 papers · 1 filter
Gibbons-Hawking Effect in the Sonic de Sitter Space-Time of an Expanding Bose-Einstein-Condensed Gas
Petr O. Fedichev, Uwe R. Fischer
We propose an experimental scheme to observe the Gibbons-Hawking effect in the acoustic analog of a 1+1-dimensional de Sitter universe, produced in an expanding, cigar-shaped Bose-…
Zero temperature damping of Bose-Einstein condensate oscillations by vortex-antivortex pair creation
Petr O. Fedichev, Uwe R. Fischer, Alessio Recati
We investigate vortex-antivortex pair creation in a supersonically expanding and contracting quasi-2D Bose-Einstein condensate at zero temperature. For sufficiently large amplitude…
On the space-time curvature experienced by quasiparticle excitations in the Painleve-Gullstrand effective geometry
Uwe R. Fischer, Matt Visser
We consider quasiparticle propagation in constant-speed-of-sound (iso-tachic) and almost incompressible (iso-pycnal) hydrodynamic flows, using the technical machinery of general re…
Existence of Long-Range Order for Trapped Interacting Bosons
Uwe R. Fischer
We derive an inequality governing ``long range'' order for a localized Bose-condensed state, relating the condensate fraction at a given temperature with effective curvature radius…
Specific heat of the Kelvin modes in low temperature superfluid turbulence
Uwe R. Fischer
It is pointed out that the specific heat of helical vortex line excitations, in low temperature superfluid turbulence experiments carried out in helium II, can be of the same order…
Short wavelength spectrum and Hamiltonian stability of vortex rings
Uwe R. Fischer, Nils Schopohl
We compare dynamical and energetical stability criteria for vortex rings. It is argued that vortex rings will be intrinsically unstable against perturbations with short wavelengths…