Haldane Exclusion Statistics and the Boltzmann Equation

We generalize the collision term in the one-dimensional Boltzmann-Nordheim transport equation for quasiparticles that obey the Haldane exclusion statistics. For the equilibrium situation, this leads to the ``golden rule'' factor for quantum transitions. As an application of this, we calculate the density response function of a one-dimensional electron gas in a periodic potential, assuming that the particle-hole excitations are quasiparticles obeying the new statistics. We also calculate the relaxation time of a nuclear spin in a metal using the modified golden rule.Comment: version accepted for publication in J. of Stat. Phy

End wall flows in rotors and stators of a single stage compressor

A computer code for solving the parabolized Navier-Stokes equations for internal flows was developed. Oscillations that develop in the calculation procedure are discussed. The measurements made in the hub and annulus wall boundary layers are summarized. The flow in the hub wall boundary layer, starting ahead of the inlet guide vanes to the inlet of the rotor is traced

Re-equilibration after quenches in athermal martensites:Conversion-delays for vapour to liquid domain-wall phases

Entropy barriers and ageing states appear in martensitic structural-transition models, slowly re-equilibrating after temperature quenches, under Monte Carlo dynamics. Concepts from protein folding and ageing harmonic oscillators turn out to be useful in understanding these nonequilibrium evolutions. We show how the athermal, non-activated delay time for seeded parent-phase austenite to convert to product-phase martensite, arises from an identified entropy barrier in Fourier space. In an ageing state of low Monte Carlo acceptances, the strain structure factor makes constant-energy searches for rare pathways, to enter a Brillouin zone `golf hole' enclosing negative energy states, and to suddenly release entropically trapped stresses. In this context, a stress-dependent effective temperature can be defined, that re-equilibrates to the quenched bath temperature.Comment: 11 pages, 12 figures. Under process with Phys. Rev. B (2015