- Email: [email protected]
Variation of parameters in cosmology
ABSTRACTS
OF
PAPERS
TO
APPEAR
IN
FUTURE
ISSUES
513
three-bound-quark neutron system, is calculated. In the Kobayashi-Maskawa model the resulting value of the moment is estimated as 0(10m33) e cm; however, strong interaction corrections (gluonic radiative corrections) give quark moment contributions which may be numerically larger (possibly 10-80*1 e cm). Either case clearly distinguishes gauge-sector CP violation from Higgs-sector CP violation, which typically gives a neutron moment of order 10eZ4e cm. Variation of Parameters in Cosmology. ROBERT T. JANTZEN. Institute of Field Physics, Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514. Parameters which appear in the solutions of the dynamical equations of spatially homogeneous cosmology or in the dynamical equations themselves are subject to algebraic relations imposed by the constraint equations, i.e., are confined to a constraint hypersurface in parameter space. Values of these parameters off the constraint hypersurface often correspond to solutions which have an additional stiff perfect fluid source that may or may not be flowing orthogonally to the spatially homogeneous foliation or to a related inhomogeneous but spatially self-similar solution or to a combination of the two. These possibilities are studied and explicitly illustrated, leading to a uniform derivation of most of the known exact anisotropic spatially homogeneous or spatially self-similar solutions as well as some new ones. Dynamics of the Crystallized One Component Plasma. H. R. GLYDE, Physics Department, University of Ottawa, Ottawa, Ontario KlN 6N5, Canada; AND G. H. KEECH, Chalk River Nuclear Laboratories, Atomic Energy of Canada Research, Co. Ltd., Chalk River, Ontario KOJ lJ0, Canada. The dynamics and energy of the crystallized one component plasma (OCP) is evaluated using the self-consistent phonon (SCP) theory of lattice dynamics. Melting of the crystal is also examined. The OCP crystal is harmonic for particle rms vibrational amplitudes as large as 25 % of the interparticle spacing. This is due to the soft (r-l) core of the Coulomb potential. Anharmonic effects are, however, entirely responsible for the eventual mechanical instability, identified here with melting, of the crystal at large enough rms amplitudes. This takes place at r, = 180 at T = 0 K for the most sophisticated SCP theory. In the classical limit, this SCP theory predicts the crystal to be more stable than does the “exact” Monte Carlo study of melting by Pollock and Hansen. This suggests that including further anharmonic terms in the SCP theory leads to melting at even larger rs at T = 0 K. However, comparison of crystal and fluid energies by Ceperley and Hansen and Mazighi suggest melting in the range rs = 65 to 135. Near melting the anharmonic contributions shift the phonon frequencies by a factor of 2 and the phonon lifetimes become very short.
OF
PAPERS
TO
APPEAR
IN
FUTURE
ISSUES
513
three-bound-quark neutron system, is calculated. In the Kobayashi-Maskawa model the resulting value of the moment is estimated as 0(10m33) e cm; however, strong interaction corrections (gluonic radiative corrections) give quark moment contributions which may be numerically larger (possibly 10-80*1 e cm). Either case clearly distinguishes gauge-sector CP violation from Higgs-sector CP violation, which typically gives a neutron moment of order 10eZ4e cm. Variation of Parameters in Cosmology. ROBERT T. JANTZEN. Institute of Field Physics, Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514. Parameters which appear in the solutions of the dynamical equations of spatially homogeneous cosmology or in the dynamical equations themselves are subject to algebraic relations imposed by the constraint equations, i.e., are confined to a constraint hypersurface in parameter space. Values of these parameters off the constraint hypersurface often correspond to solutions which have an additional stiff perfect fluid source that may or may not be flowing orthogonally to the spatially homogeneous foliation or to a related inhomogeneous but spatially self-similar solution or to a combination of the two. These possibilities are studied and explicitly illustrated, leading to a uniform derivation of most of the known exact anisotropic spatially homogeneous or spatially self-similar solutions as well as some new ones. Dynamics of the Crystallized One Component Plasma. H. R. GLYDE, Physics Department, University of Ottawa, Ottawa, Ontario KlN 6N5, Canada; AND G. H. KEECH, Chalk River Nuclear Laboratories, Atomic Energy of Canada Research, Co. Ltd., Chalk River, Ontario KOJ lJ0, Canada. The dynamics and energy of the crystallized one component plasma (OCP) is evaluated using the self-consistent phonon (SCP) theory of lattice dynamics. Melting of the crystal is also examined. The OCP crystal is harmonic for particle rms vibrational amplitudes as large as 25 % of the interparticle spacing. This is due to the soft (r-l) core of the Coulomb potential. Anharmonic effects are, however, entirely responsible for the eventual mechanical instability, identified here with melting, of the crystal at large enough rms amplitudes. This takes place at r, = 180 at T = 0 K for the most sophisticated SCP theory. In the classical limit, this SCP theory predicts the crystal to be more stable than does the “exact” Monte Carlo study of melting by Pollock and Hansen. This suggests that including further anharmonic terms in the SCP theory leads to melting at even larger rs at T = 0 K. However, comparison of crystal and fluid energies by Ceperley and Hansen and Mazighi suggest melting in the range rs = 65 to 135. Near melting the anharmonic contributions shift the phonon frequencies by a factor of 2 and the phonon lifetimes become very short.