Building on a general variational framework for multi-fluid dynamics, we discuss finite temperature effects in superfluids. The main aim is to provide insight into the modelling of more complex finite temperature superfluid systems, like the mixed neutron superfluid/proton superconductor that is expected in the outer core of a neutron star. Our final results can also (to a certain extent) be us...

The analogues of r-modes in superfluid neutron stars are studied here. These modes, which are governed primarily by the Coriolis force, are identical to their ordinary-fluid counterparts at the lowest order in the small angular-velocity expansion used here. The equations that determine the next order terms are derived and solved numerically for fairly realistic superfluid neutron-star models. T...

We report the first measurements of negative ion motion in the superfluid phases of 3He and in the normal phase below 17 inK. Refrigeration was achieved with nuclear demagnetization of copper and we used a pulsed NMR platinum powder thermometer immersed in the liquid. In the A phase the longitudinal resonance frequency provided an additional high-resolution thermometer. In the normal phase we o...

We investigate the superfluid-insulator transition in the disordered two-dimensional Bose-Hubbard model through quantum Monte Carlo simulations. The Bose-Hubbard model is studied in the presence of site disorder and the quantum critical point between the Bose-glass and superfluid is determined in both the grand canonical (μ/U = 0.375 close to ρ = 1) and canonical ensemble (ρ = 1 and 0.5). Parti...

At asymptotic high density and low temperature quarks form Cooper pairs in a color-flavor locked (CFL) configuration. The diquark condensates break spontaneously the baryon symmetry, and this fact makes the CFL phase also superfluid. At low temperatures the transport properties are dominated by the contribution of the superfluid phonon, the Goldstone boson associated to baryon symmetry breaking...

This article suggests a preliminary version of a Cantorian superfluid vortex hypothesis as a plausible model of nonlinear cosmology. Though some parts of the proposed theory resemble several elements of what have been proposed by Consoli (2000, 2002), Gibson (1999), Nottale (1996, 1997, 2001, 2002a), and Winterberg (2002b), it seems such a Cantorian superfluid vortex model instead of superfluid...

We study the entanglement spectrum (ES) of the Bose-Hubbard model on the two-dimensional square lattice at unit filling, both in the Mott insulating and in the superfluid phase. In the Mott phase, we demonstrate that the ES is dominated by the physics at the boundary between the two subsystems. On top of the boundary-local (perturbative) structure, the ES exhibits substructures arising from one...

The role of aerogel as a means of introducing correlated disorder into superfluid He is examined in this paper. The aerogel structure is described by a diffusion-limited cluster aggregation model and compared to the results of small-angle x-ray scattering obtained from samples that were used to study the suppression of Tc as well as the development of the superfluid fraction. These results high...

Correlation effects in nuclear matter at finite temperatures are studied for subnuclear densities (ρ < ρ0) and medium excitation energy, where a nonrelativistic potential approach is possible. A quantum statistical approach is given, where clusters are treated under the influence of a clustered medium treated within a mean field approximation. Spectral functions, in-medium cross sections, and r...

We consider the intermittent behavior of superfluid turbulence in (4)He. Because of the similarity in the nonlinear structure of the two-fluid model of superfluidity and the Euler and Navier-Stokes equations, one expects the scaling exponents of the structure functions to be the same as in classical turbulence for temperatures close to the superfluid transition T(λ) and also for T << T(λ). This...