1,655,561 research outputs found
Solving the Cosmological Moduli Problem with Weak Scale Inflation
Many models of supersymmetry breaking involve particles with weak scale mass
and Planck mass suppressed couplings. Coherent production of such particles in
the early universe destroys the successful predictions of nucleosynthesis. We
show that this problem may be solved by a brief period of weak scale inflation.
Furthermore the inflaton potential for such an inflation naturally arises from
the same assumptions which lead to the cosmological problem. Successful
baryogenesis and preservation of density fluctuations for large scale structure
formation are also possible in this scenario.Comment: 21 pages, MIT-CTP-2331, NSF-ITP-94-70, SCIPP 94-16, uses phyzz
Standard Model Baryogenesis
Simply on CP arguments, we argue against a Standard Model explanation of
baryogenesis via the charge transport mechanism. A CP-asymmetry is found in the
reflection coefficients of quarks hitting the electroweak phase boundary
created during a first order phase transition. The problem is analyzed both in
an academic zero temperature case and in the realistic finite temperature one.
At finite temperature, a crucial role is played by the damping rate of
quasi-quarks in a hot plasma, which induces loss of spatial coherence and
suppresses reflection on the boundary even at tree-level. The resulting baryon
asymmetry is many orders of magnitude below what observation requires. We
comment as well on related works.Comment: 10 pages, CERN-TH. 7368/94, LPTHE Orsay-94/71, HD-THEP-94-2
Two electrons in an external oscillator potential: hidden algebraic structure
It is shown that the Coulomb correlation problem for a system of two
electrons (two charged particles) in an external oscillator potential possesses
a hidden -algebraic structure being one of recently-discovered
quasi-exactly-solvable problems. The origin of existing exact solutions to this
problem, recently discovered by several authors, is explained. A degeneracy of
energies in electron-electron and electron-positron correlation problems is
found. It manifests the first appearence of hidden -algebraic structure
in atomic physics.Comment: 7 pages (plus one figure avaliable via direct request), LaTeX,
Preprint IFUNAM FT 94-4
Integrable boundary conditions for classical sine-Gordon theory
The possible boundary conditions consistent with the integrability of the
classical sine-Gordon equation are studied. A boundary value problem on the
half-line with local boundary condition at the origin is considered.
The most general form of this boundary condition is found such that the problem
be integrable. For the resulting system an infinite number of involutive
integrals of motion exist. These integrals are calculated and one is identified
as the Hamiltonian. The results found agree with some recent work of Ghoshal
and Zamolodchikov.Comment: 10 pages, DTP/94-3
Kinetic Inflation in Stringy and Other Cosmologies
An inflationary epoch driven by the kinetic energy density in a dynamical
Planck mass is studied. In the conformally related Einstein frame it is easiest
to see the demands of successful inflation cannot be satisfied by kinetic
inflation alone. Viewed in the original Jordan-Brans-Dicke frame, the obstacle
is manifest as a kind of graceful exit problem and/or a kind of flatness
problem. These arguments indicate the weakness of only the simplest
formulation. {}From them can be gleaned directions toward successful kinetic
inflation.Comment: 26 pages, LaTeX, CITA-94-2
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