82,212 research outputs found
Complex Monge-Amp\`ere equations on quasi-projective varieties
We introduce generalized Monge-Amp\`ere capacities and use these to study
complex Monge-Amp\`ere equations whose right-hand side is smooth outside a
divisor. We prove, in many cases, that there exists a unique normalized
solution which is smooth outside the divisor
The viscoplasticity theory based on overstress applied to the modeling of a nickel base superalloy at 815 C
Short term strain rate change, creep and relaxation tests were performed in an MTS computer controlled servohydraulic testing machine. Aging and recovery were found to be insignificant for test times not exceeding 30 hrs. The material functions and constants of the theory were identified from results of strain rate change tests. Numerical integration of the theory for relaxation and creep tests showed good predictive capabilities of the viscoplasticity theory based on overstress
De Sitter Bounces
By analytically continuing recently-found instantons, we construct
time-dependent solutions of Einstein-Maxwell de Sitter gravity which smoothly
bounce between two de Sitter phases. These deformations of de Sitter space
undergo several stages in their time evolution. Four and five-dimensional de
Sitter bounces can be lifted to non-singular time-dependent solutions of
M-theory.Comment: Latex, 18 pages, 5 figure
The Static Dielectric Constant of a Colloidal Suspension
We derive an expression for the static dielectric constant of the colloidal
susp ensions based on the electrokinetic equations. The analysis assumes that
the ions have the same diffusivity, and that the double layer is much thinner
than the radius of curvature of the particles. It is shown that the dielectric
increment of the double layer polarization mechanism is originated from the
free energy stored in the salt concentration inhomogeniety. We also show that
the dominant polarization charges in the theory are at the electrodes, rather
than close to the particles.Comment: 15 pages, 1 figur
Spectrum-generating Symmetries for BPS Solitons
We show that there exist nonlinearly realised duality symmetries that are
independent of the standard supergravity global symmetries, and which provide
active spectrum-generating symmetries for the fundamental BPS solitons. The
additional ingredient, in any spacetime dimension, is a single scaling
transformation that allows one to map between BPS solitons with different
masses. Without the inclusion of this additional transformation, which is a
symmetry of the classical equations of motion, but not the action, it is not
possible to find a spectrum-generating symmetry. The necessity of including
this scaling transformation highlights the vulnerability of duality multiplets
to quantum anomalies. We argue that fundamental BPS solitons may be immune to
this threat.Comment: References added. Latex, 29 page
Dilatonic p-brane solitons
We find new 4-brane and 5-brane solitons in massive gauged , and
, supergravities. In each case, the solutions preserve half of the
original supersymmetry. These solutions make use of the metric and dilaton
fields only. We also present more general dilatonic -branes in
dimensions.Comment: 9 pages, Latex, no figure
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