Site percolation thresholds are reproduced in all dimensions for all lattices using a linear combination of two analytic terms. One is the well known Cayley tree percolation threshold which is believed to be exact at infinite dimension. The other one is obtained from a new approach to...

We report a quasi-exact power law behavior for Ising critical temperatures on hypercubes. It reads JkBTc = K0[(1 − 1/d)(q−1)]a where K0 = 0.8633747, d is the space dimension q the coordination number (q = 2d), J the coupling constant kB the Boltzman constant and Tc the critical temperature....

The two-time correlation function Cxx(t,t′) of the displacement x(t)−x(t0) of a free quantum Brownian particle with respect to its position at a given time t0 is calculated analytically in the framework of the Caldeira and Leggett ohmic dissipation model. As a result, at any temperature...

A time-domain formulation of the equilibrium quantum fluctuation–dissipation theorem (FDT) in the whole range of temperatures is presented. In the classical limit, the FDT establishes a proportionality relation between the dissipative part of the linear response function and the derivative of...

We report new results about the anomalous diffusion of a particle in an aging medium. For each given age, the quasi-stationary particle velocity is governed by a generalized Langevin equation with a frequency-dependent friction coefficient proportional to |ω|δ−1 at small frequencies, with...

Financial economic models often assume that investors know (or agree on) the fundamental value of the shares of the firm, easing the passage from the individual to the collective dimension of the financial system generated by the Share Exchange over time. Our model relaxes that heroic assumption...

The substantial turmoil created by both 2000 dot-com crash and 2008 subprime crisis has fueled the belief that the two classical paradigms of economics, which are the invisible hand and the rational agent, are not appropriate to describe market dynamics and should be abandoned at the benefit of...

Since the attribution of the Nobel prize in 2002 to Kahneman for prospect theory, behavioral finance has become an increasingly important subfield of finance. However the main parts of behavioral finance, prospect theory included, understand financial markets through individual investment...

Public debates driven by incomplete scientific data where nobody can claim absolute certainty, due to the current state of scientific knowledge, are studied. The cases of evolution theory, global warming and H1N1 pandemic influenza are investigated. The first two are of controversial impact...

Some universal features are independent of both the social nature of the individuals making the decision and the nature of the decision itself. On this basis a simple magnet like model is built. Pair interactions are introduced to measure the degree of exchange among individuals while...