Related papers: Cosmology, Particle Physics and Superfluid 3He
3He atoms dissolved in superfluid 4He may form dimers (3He)2 in two-dimensional geometries. We study dimer formation in films of dilute 3He-4He mixture. After designing a schematic 3He-3He interaction potential we calculate the dimer…
We propose a new model for the nature of the nucleation of solid from the superfluid phases of $^4$He and $^3$He. Unique to the superfluid phases the solid nucleation involves an extremely fast solidification front. This results in a local…
We report the first observation of superfluid $\beta$ phase of $^3$He. This phase is realized in $^3$He in nematic aerogel in presence of high magnetic field right below the superfluid transition temperature. We use a vibrating aerogel…
Kibble and Zurek have provided a unifying causal picture for the appearance of classical defects like cosmic strings or vortices at the onset of phase transitions in relativistic QFT and condensed matter systems respectively. In condensed…
We provide a pedagogical overview of defect models of structure formation. We first introduce the concept of topological defect, and describe how to classify them. We then show how defects might be produced in phase transitions in the Early…
We show that, for the scalar field cosmology with exponential potential, the set of values of the coupling parameter for which the solutions undergo a transient period of acceleration is much larger than the set discussed in the literature.…
We report results of experiments with superfluid 3He confined in aerogels with parallel strands which lead to anisotropic scattering of 3He quasiparticles. We vary boundary conditions for the scattering by covering the strands by different…
Surface waves on both superfluid 3He and 4He were examined with the premise, that these inviscid media would represent ideal realizations for this fluid dynamics problem. The work on 3He is one of the first of its kind, but on 4He it was…
In inflationary cosmology, the rapid expansion of the early universe resulted in the spontaneous production of cosmological particles from vacuum fluctuations, observable today in the cosmic microwave background anisotropies. The analogue…
Liquid 3He at low temperatures is an ideal substance to study because of its natural purity. The superfluid state, which appears at temperatures below 3 mK, has many unusual and exciting properties. These have extensively been studied…
The different superfluid phases of $^3$He are described by $p$-wave order parameters that include anisotropy axes both in the orbital and spin spaces. The anisotropy axes characterize the broken symmetries in these macroscopically coherent…
Quantum-degenerate Fermi gases provide a remarkable opportunity to study strongly interacting fermions. In contrast to other Fermi systems, such as superconductors, neutron stars or the quark-gluon plasma, these gases have low densities and…
Superfluidity is an emergent quantum phenomenon which arises due to strong interactions between elementary excitations in liquid helium. These excitations have been probed with great success using techniques such as neutron and light…
The magnetic dipole-dipole interaction does not prevent existence of half-quantum vortices in the polar phase of superfluid He-3 which can be stable in uniaxial anisotropic aerogel. Here we discus this exotic possibility. After developing a…
We entertain the possibility that the phenomena typically attributed to dark matter may have a fundamentally emergent nature, rather than arising from new particle degrees of freedom. To illustrate this idea, we consider a field-theoretic…
Neutron stars make a unique astrophysical test bench for our understanding of quantum physics at kilometre scales. The rotation of a neutron star features glitches, sudden spin-ups that interrupt the otherwise regular stellar spin-down,…
Many particle physics models of matter admit solutions corresponding to stable or long-lived topological defects. In the context of standard cosmology it is then unavoidable that such defects will form during phase transitions in the very…
Steady-state turbulent motion is created in superfluid 3He-B at low temperatures in the form of a turbulent vortex front, which moves axially along a rotating cylindrical container of 3He-B and replaces vortex-free flow with vortex lines at…
Ultracold quantum gases are highly controllable and, thus, capable of simulating difficult quantum many-body problems ranging from condensed matter physics to astrophysics. Although experimental realizations have so far been restricted to…
The experimental investigation of superfluid turbulence in 3He-B is generally not possible with the techniques which have been developed for 4He-II. We describe a new method by which a transient burst of turbulent vortex expansion can be…