In this work we present a calculation of the quasi-normal modes Planck star, supposed state in life large mass star which quantum effects should reverse collapse causing to explode. order solve Regge–Wheeler equations and calculate modes, apply shooting method. • We have derived for star. calculated perturbed Einstein Quasi Normal Modes

We study the phase transition of a gas of Rb atoms to quantum degeneracy in the combined potential of a harmonically confining magnetic trap and the periodic potential of an optical lattice. For high optical lattice potentials we observe a significant change in the temperature dependency of the population of the ground state of the system. The experimental results are explained by the subsequen...

For a homogeneous space G/P , where P is a parabolic subgroup of a complex semisimple group G, an explicit Kähler–Einstein metric on it is constructed. The Einstein constant for the metric is 1. Therefore, the intersection number of the first Chern class of the holomorphic tangent bundle of G/P coincides with the volume of G/P with respect to this Kähler–Einstein metric, thus enabling us to com...

We analyze the effects of a random magnetic potential in a microfabricated waveguide for ultracold atoms. We find that the shape and position fluctuations of a current carrying wire induce a strong Gaussian correlated random potential with a length scale set by the atom-wire separation. The theory is used to explain quantitatively the observed fragmentation of the Bose-Einstein condensates in a...

In the framework of the Hartle-Hawking no-boundary proposal, we investigated quantum creation of the multidimensional universe with a cosmological constant (Λ) but without matter fields. We have found that the classical solutions of the Euclidean Einstein equations in this model have “quasi-attractors”, i.e., most trajectories on the a-b plane, where a and b are the scale factors of external an...

– We study theoretically the dimensional crossover from a three-dimensional elongated condensate to a one-dimensional condensate as the transverse degrees of freedom get frozen by tight confinement, in the limit of small density fluctuations, i.e. for a strongly degenerate gas. We compute analytically the radially integrated density profile at low temperatures using a local density approximatio...

Properties of the Einstein equations in a coordinate gauge based on expanding null hypersurfaces foliated by metric 2-spheres are described. This null quasi-spherical (NQS) gauge leads to particularly simple analyses of the characteristic structure of the equations and of the propagation of gravitational shocks, and clarifies the geometry of timelike boundary condition. A feature of the NQS gau...

We define quasi-local conserved quantities in general relativity by using the optimal isometric embedding in [28] to transplant Killing fields in the Minkowski spacetime back to the 2-surface of interest in a physical spacetime. To each optimal isometric embedding, a dual element of the Lie algebra of the Lorentz group is assigned. Quasi-local angular momentum and quasi-local center of mass cor...