A Note on Schwinger Mechanism and a Nonabelian Instability in a Nonabelian Plasma

We point out that there is a nonabelian instability for a nonabelian plasma which does not allow both for a net nonzero color charge and the existence of field configurations which are coherent over a volume $v$ whose size is determined by the chemical potential. The basic process which leads to this result is the Schwinger decay of chromoelectric fields, for the case where the field arises from commutators of constant potentials, rather than as the curl of spacetime dependent potentials. In terms of the fields, instability is obtained when Tr(DF)^2 > 0.Comment: 14 pages, 6 figure

Biexciton recombination rates in self-assembled quantum dots

The radiative recombination rates of interacting electron-hole pairs in a quantum dot are strongly affected by quantum correlations among electrons and holes in the dot. Recent measurements of the biexciton recombination rate in single self-assembled quantum dots have found values spanning from two times the single exciton recombination rate to values well below the exciton decay rate. In this paper, a Feynman path-integral formulation is developed to calculate recombination rates including thermal and many-body effects. Using real-space Monte Carlo integration, the path-integral expressions for realistic three-dimensional models of InGaAs/GaAs, CdSe/ZnSe, and InP/InGaP dots are evaluated, including anisotropic effective masses. Depending on size, radiative rates of typical dots lie in the regime between strong and intermediate confinement. The results compare favorably to recent experiments and calculations on related dot systems. Configuration interaction calculations using uncorrelated basis sets are found to be severely limited in calculating decay rates.Comment: 11 pages, 4 figure

Phosphate mediated changes in phospholipids in Neurospora crassa.

Phosphate mediated changes in phospholipids in Neurospora crassa

Influence of bond orientational order on the switching time of ferroelectric smectics

We report studies of the bulk switching time as a function of temperature in the chiral smectic C (C∗ ) and chiral smectic I (I∗) phases of 4-(2-methylbutyl) phenyl 4'-(octyloxy)-(1,1')-biphenyl-4-carboxylate (8OSI) which shows a continuous evolution from the fluid C∗ to the hexatic I∗ phase. The thermal variation of the switching time is found (to our knowledge for the first time) to scale remarkably well with the hexatic order parameter for the two phases determined experimentally by Brock et al for 8OSI, the racemic form of 8OSI. Similar correlation is observed in the case of 8SI∗, the alkyl analog of 8OSI∗, which shows a first order C∗-I∗ transition

Phosphate mediated changes in fatty acid composition in Neurospora crassa.

Phosphate mediated changes in fatty acid composition in Neurospora crassa

Calcium effects in Neurospora crassa

Calcium effects in N. crass