2,593 research outputs found
Compromising in Partition Function Form Games and Cooperation in Perfect Extensive Form
In this paper reasonable payoff intervals for players in a game in partition function form (p.f.f.game) are introduced and used to define the notion of compromisable p.f.f. game.For a compromisable p.f.f. game a compromise value is defined for which an axiomatic characterization is provided.Also a generic subclass of games in extensive form of perfect information without chance moves is introduced.For this class of perfect extensive form games there is a natural credible way to define a p.f.f. game if the players consider cooperation.It turns out that the p.f.f. games obtained in this way are compromisable.game theory
A deformed QRPA formalism for single and two-neutrino double beta decay
We use a deformed QRPA formalism to describe simultaneously the energy
distributions of the single beta Gamow-Teller strength and the two-neutrino
double beta decay matrix elements. Calculations are performed in a series of
double beta decay partners with A = 48, 76, 82, 96, 100, 116, 128, 130, 136 and
150, using deformed Woods-Saxon potentials and deformed Skyrme Hartree-Fock
mean fields. The formalism includes a quasiparticle deformed basis and residual
spin-isospin forces in the particle-hole and particle-particle channels. We
discuss the sensitivity of the parent and daughter Gamow-Teller strength
distributions in single beta decay, as well as the sensitivity of the double
beta decay matrix elements to the deformed mean field and to the residual
interactions. Nuclear deformation is found to be a mechanism of suppression of
the two-neutrino double beta decay. The double beta decay matrix elements are
found to have maximum values for about equal deformations of parent and
daughter nuclei. They decrease rapidly when differences in deformations
increase. We remark the importance of a proper simultaneous description of both
double beta decay and single Gamow-Teller strength distributions. Finally, we
conclude that for further progress in the field it would be useful to improve
and complete the experimental information on the studied Gamow-Teller strengths
and nuclear deformations.Comment: 33 pages, 19 figures. To be published in Phys. Rev.
Role of three-body interactions in formation of bulk viscosity in liquid argon
With the aim of locating the origin of discrepancy between experimental and
computer simulation results on bulk viscosity of liquid argon, a molecular
dynamic simulation of argon interacting via ab initio pair potential and
triple-dipole three-body potential has been undertaken. Bulk viscosity,
obtained using Green-Kubo formula, is different from the values obtained from
modeling argon using Lennard-Jones potential, the former being closer to the
experimental data. The conclusion is made that many-body inter-atomic
interaction plays a significant role in formation of bulk viscosity.Comment: 4 pages, 3 figure
Fuzzy Clan Games and Bi-monotonic Allocation Rules
Clan game;Big boss game;Core;Decision making;Fuzzy coalition;Fuzzy game;Monotonic allocation rule
Phase transitions in systems with two species of molecular motors
Systems with two species of active molecular motors moving on (cytoskeletal)
filaments into opposite directions are studied theoretically using driven
lattice gas models. The motors can unbind from and rebind to the filaments. Two
motors are more likely to bind on adjacent filament sites if they belong to the
same species. These systems exhibit (i) Continuous phase transitions towards
states with spontaneously broken symmetry, where one motor species is largely
excluded from the filament, (ii) Hysteresis of the total current upon varying
the relative concentrations of the two motor species, and (iii) Coexistence of
traffic lanes with opposite directionality in multi-filament systems. These
theoretical predictions should be experimentally accessible.Comment: 7 pages, 4 figures, epl style (.cls-file included), to appear in
Europhys. Lett. (http://www.edpsciences.org/epl
Stepwise Projection: Toward Brane Setups for Generic Orbifold Singularities
The construction of brane setups for the exceptional series E6,E7,E8 of SU(2)
orbifolds remains an ever-haunting conundrum. Motivated by techniques in some
works by Muto on non-Abelian SU(3) orbifolds, we here provide an algorithmic
outlook, a method which we call stepwise projection, that may shed some light
on this puzzle. We exemplify this method, consisting of transformation rules
for obtaining complex quivers and brane setups from more elementary ones, to
the cases of the D-series and E6 finite subgroups of SU(2). Furthermore, we
demonstrate the generality of the stepwise procedure by appealing to Frobenius'
theory of Induced Representations. Our algorithm suggests the existence of
generalisations of the orientifold plane in string theory.Comment: 22 pages, 3 figure
Spin-filter tunnel junction with matched Fermi surfaces
Efficient injection of spin-polarized current into a semiconductor is a basic
prerequisite for building semiconductor-based spintronic devices. Here, we use
inelastic electron tunneling spectroscopy to show that the efficiency of
spin-filter-type spin injectors is limited by spin scattering of the tunneling
electrons. By matching the Fermi-surface shapes of the current injection source
and target electrode material, spin injection efficiency can be significantly
increased in epitaxial ferromagnetic insulator tunnel junctions. Our results
demonstrate that not only structural but also Fermi-surface matching is
important to suppress scattering processes in spintronic devices.Comment: 5 pages, 4 figure
Shell Model Study of the Double Beta Decays of Ge, Se and Xe
The lifetimes for the double beta decays of Ge, Se and
Xe are calculated using very large shell model spaces. The two neutrino
matrix elements obtained are in good agreement with the present experimental
data. For eV we predict the following upper bounds to the
half-lives for the neutrinoless mode: , and . These results are the first from a new generation of Shell
Model calculations reaching O(10) dimensions
Effect of doping and oxygen vacancies on the octahedral tilt transitions in the BaCeO3 perovskite
We present a systematic study of the effect of Y doping and hydration level
on the structural transformations of BaCeO3 based on anelastic spectroscopy
experiments. The temperature of the intermediate transformation between
rhombohedral and orthorhombic Imma phases rises with increasing the molar
fraction x of Y roughly as (500 K)x in the hydrated state, and is depressed of
more than twice that amount after complete dehydration. This is explained in
terms of the effect of doping on the average (Ce/Y)-O and Ba-O bond lengths,
and of lattice relaxation from O vacancies. The different behavior of the
transition to the lower temperature Pnma orthorhombic phase is tentatively
explained in terms of progressive flattening of the effective shape of the OH
ion and ordering of the O vacancies during cooling.Comment: 8 pages, 5 figure
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