Crossover properties from random percolation to frustrated percolation

We investigate the crossover properties of the frustrated percolation model on a two-dimensional square lattice, with asymmetric distribution of ferromagnetic and antiferromagnetic interactions. We determine the critical exponents nu, gamma and beta of the percolation transition of the model, for various values of the density of antiferromagnetic interactions pi in the range 0<pi<0.5. Our data are consistent with the existence of a crossover from random percolation behavior for pi=0, to frustrated percolation behavior, characterized by the critical exponents of the ferromagnetic 1/2-state Potts model, as soon as pi>0.Comment: 5 pages, 7 figs, RevTe

A Theory of time-varying Constants

We present a flat (K=0) cosmological model, described by a perfect fluid with the ``constants'' $G,c$ and $\Lambda$ varying with cosmological time $t$. We introduce Planck\'s ``constant'' $\hbar$ in the field equations through the equation of state for the energy density of radiation. We then determine the behaviour of the ``constants'' by using the zero divergence of the second member of the modified Einstein\'s field equations i.e. $div(\frac{G}{c^{4}}T_{i}^{j}+\delta_{i}^{j}\Lambda)=0,$ together with the equation of state and the Einstein cosmological equations. Assuming realistic physical and mathematical conditions we obtain a consistent result with $\hbar c=constant$. In this way we obtain gauge invariance for the Schr\"{o}dinger equation and the behaviour of the remaining ``constants''Comment: 15 pages, RevTeX

Balanced and Imbalanced Societal Norms About Working: A Comparison of Four National Labor Markets at Two Time Points

Two normative orientations: work as an obligation/duty versus work as an entitlement/right are compared among representative samples from the American, German, Belgian, and Japanese labor force exploring four domains: Work itself\u27, Meaningful work , Work Improvements , and Care for the Future at two points in time. Results reveal: Stability over time, and significant differences related to age, occupational group membership, and country

How Working is Defined: Structure and Stability

[Excerpt] Multidimensional scaling of statements that identify when individuals consider an activity in which one is engaged to be working was conducted on representative samples of the employed labor forces in Belgium, Germany, Japan and the USA at the time period 1982-83 and again at the time period 1989-92. Representative labor force samples of the employed labor forces in East Germany, Bulgaria, the Czech Republic, Hungary, Poland, Slovakia and Beijing, China studied at the time period 1991-92 were subjected to the same MDS analysis. The results provide strong support that one dominant dimension underlying the way in which people define working ranges from individual cost to social contribution. Individuals who define working in burden and/or constraint terms emphasize costs to the individual. Individuals who define working largely in responsibility and exchange terms emphasize reciprocal exchange relations between the individual and the organization/society. Individuals who define working largely in social contribution terms emphasize the social benefits of working. The work definition structures found in each of the four countries with replication samples are quite stable over time. In total, the work definition responses of over 18,000 individuals were studied

Studies of thermal conductivity in Fermi-Pasta-Ulam like lattices

The pioneering computer simulations of the energy relaxation mechanisms performed by Fermi, Pasta and Ulam can be considered as the first attempt of understanding energy relaxation and thus heat conduction in lattices of nonlinear oscillators. In this paper we describe the most recent achievements about the divergence of heat conductivity with the system size in 1d and 2d FPU-like lattices. The anomalous behavior is particularly evident at low energies, where it is enhanced by the quasi-harmonic character of the lattice dynamics. Remakably, anomalies persist also in the strongly chaotic region where long--time tails develop in the current autocorrelation function. A modal analysis of the 1d case is also presented in order to gain further insight about the role played by boundary conditions.Comment: Invited article to appear in the Chaos focus issue on "Studies of Nonlinear Problems. I" by Enrico Fermi, John Pasta, and Stanislaw Ulam

Largest temperature of the radiation era and its cosmological implications

The thermal history of the universe before the epoch of nucleosynthesis is unknown. The maximum temperature in the radiation-dominated era, which we will refer to as the reheat temperature, may have been as low as 0.7 MeV. In this paper we show that a low reheat temperature has important implications for many topics in cosmology. We show that weakly interacting massive particles (WIMPs) may be produced even if the reheat temperature is much smaller than the freeze-out temperature of the WIMP, and that the dependence of the present abundance on the mass and the annihilation cross section of the WIMP differs drastically from familiar results. We revisit predictions of the relic abundance and resulting model constraints of supersymmetric dark matter, axions, massive neutrinos, and other dark matter candidates, nucleosynthesis constraints on decaying particles, and leptogenesis by decay of superheavy particles. We find that the allowed parameter space of supersymmetric models is altered, removing the usual bounds on the mass spectrum; the cosmological bound on massive neutrinos is drastically changed, ruling out Dirac (Majorana) neutrino masses $m_\nu$ only in the range 33 keV \simlt m_\nu\simlt 6 (5) MeV, which is significantly smaller from the the standard disallowed range 94 eV \simlt m_\nu\simlt 2 GeV (this implies that massive neutrinos may still play the role of either warm or cold dark matter); the cosmological upper bound on the Peccei-Quinn scale may be significantly increased to $10^{16}$GeV from the usually cited limit of about $10^{12}$GeV; and that efficient out-of-equilibrium GUT baryogenesis and/or leptogenesis can take place even if the reheat temperature is much smaller than the mass of the decaying superheavy particle.Comment: 27 pages. LaTeX (using revtex) with 10 eps figures embedded using epsf Revised version, with changes mostly in the section on the relic neutrino density in low-reheat model

On Suicidal punishment among "Acromyrmex Versicolor" Cofoundresses: the Disadvantage in Personal Advantage

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