We consider almost-complex structures on P whose total Chern classes differ from that of the standard (integrable) almost-complex structure. E. Thomas established the existence of many such structures. We show that if there exists an “exotic” integrable almost-complex structures, then the resulting complex manifold would have specific Hodge numbers which do not vanish. We also give a necessary ...

The detectability of charged SLAC-bag type structures is considered. These objects, known as Fermi balls, arise from the spontaneous symmetry breaking of a biased discrete symmetry in the early universe. Two classes of experimental searches are discussed. Since Fermi balls in the theoretically favoured mass range are absorbed by the atmosphere, direct experimental searches are confined to space...

We analyze the possibility of a ferroelectric transition in heteronuclear molecules consisting of Bose-Bose, Bose-Fermi, or Fermi-Fermi atom pairs. This transition is characterized by the appearance of a spontaneous electric polarization below a critical temperature. We discuss the existence of a ferroelectric Fermi liquid phase for Fermi molecules and the existence of a ferroelectric superflui...

Nonrelativistic Fermi liquids in d+1 dimensions exhibit generalized Fermi surfaces: (d-p)-dimensional submanifolds in the (k,omega)-space supporting gapless excitations. We show that the universality classes of stable Fermi surfaces are classified by K theory, with the pattern of stability determined by Bott periodicity. The Atiyah-Bott-Shapiro construction implies that the low-energy modes nea...

Trapped degenerate atomic gases provide exciting opportunities for the manipulation and quantitative study of quantum statistical effects, such as the strikingly direct observation of Bose-Einstein condensation @1–3#. Although perhaps not as dramatic as the phase transition associated with bosons, the behavior of trapped Fermi gases also merits attention, both as a degenerate quantum system in ...

We demonstrate a new method for determining the Fermi velocity in quasi-two-dimensional (Q2D) conductors. Application of a magnetic field parallel to the conducting layers results in periodic open orbit quasiparticle trajectories along the Q2D Fermi surface. Averaging of this motion over the Fermi surface leads to a resonance in the interlayer microwave conductivity. The resonance frequency is ...

Persistent currents driven by a static magnetic flux parallel to the carbon nanotube axis are investigated. Owing to the hexagonal symmetry of graphene the Fermi contour expected for a 2D-lattice reduces to two points. However the electron or hole doping shifts the Fermi energy upwards or downwards and as a result, the shape of the Fermi surface changes. Such a hole doping leading to the Fermi ...

We discuss spectra calculated for the two-dimensional Hubbard model in the intermediate coupling regime with the dynamical cluster approximation, which is a nonperturbative approach. We find a crossover from a normal Fermi liquid with a Fermi surface closed around the Brillouin-zone center at large doping to a nonFermi liquid for small doping where the Fermi surface is holelike, closed around M...

Shell effects in the coordinate space can be seen with degenerate Fermi vapors in non-uniform trapping potentials. In particular, below the Fermi temperature, the density profile of a Fermi gas in a confining harmonic potential is characterized by several local maxima. This effect is enhanced for ”magic numbers” of particles and in quasi-1D (cigar-shaped) configurations. In the case of a multi-...

We place the Thomas-Fermi model of the quantum theory of atoms, molecules, and solids on a firm mathematical footing. Our results include: (1) A proof of existence and uniqueness of solutions of the nonlinear Thomas-Fermi equations as well as the fact that these solutions minimize the Thomas-Fermi energy functional, (2) a proof that in a suitable large nuclear charge limit, the quantum mechanic...