Logical, mechanical and historical time in economics

Within the economic theory different notions of time imply alternative analytical structures. This article discusses and rejects the methodological dichotomy between ‘temporal’ and ‘a-temporal’ models (equilibrium and disequilibrium models) in economics. Different notions of time are identified –logical, mechanical and historical time- which enable to specify corresponding sequential methods and to address different questions within the economic theory. Some analytical implications are examined. In the light of the proposed methodological distinction different theories of the rate of interest are evaluated and new light is thrown on the important debate on finance which arose in the ‘30s among Keynes, Robertson and representatives of the Swedish School (Ohlin).Time and causality in economics; Keynes,Robertson and the Swedish School on finance

Quasinormal modes of Charged Regular Black Hole

The quasinormal modes (QNMs) of a regular black hole with charge are calculated in the eikonal approximation. In the eikonal limit the QNMs of black hole are determined by the parameters of the unstable circular null geodesics. The behaviors of QNMs are compared with QNMs of Reisner-Nordstr\"{o}m black hole, it is done by fixing some of the parameters that characterize the black holes and varying another. We observed that the parameter that is related one effective cosmological constant at small distances , determines the behaviors of the QNMs of regular black hole with charge.Comment: arXiv admin note: text overlap with arXiv:1607.0247

Microscopic mechanism of water diffusion in glucose glasses

The preservation of biomaterials depends critically on the mobility of water in the glassy state, manifested as a secondary beta relaxation and diffusion. We use coarse grain simulations to elucidate the molecular mechanism underlying the relaxations for water-glucose glass, finding two pathways for water diffusion: (i) water jumps into neighbor water positions (linking to water structure), and (ii) water jumps into glucose positions (coupling to glucose rotation). This work suggests strategies for enhancing preservation by stiffening the segmental motions of the carbohydrates

Clarifying spherical collapse in coupled dark energy cosmologies

The spherical collapse model is often used to follow the evolution of overdensities into the nonlinear regime. We describe the correct approach to be used in coupled dark energy cosmologies, where a fifth force, different from gravity and mediated by the dark energy scalar field, influences the collapse. We reformulate the spherical collapse description by deriving it directly from the set of nonlinear hydrodynamical Navier Stokes equations. By comparing with the corresponding relativistic equations, we show how the fifth force should be taken into account within the spherical collapse picture and clarify the problems arising when an inhomogeneous scalar field is considered within a spherical collapse picture. We then apply our method to the case of coupled quintessence, where the fifth force acts among cold dark matter particles, and to growing neutrino quintessence, where the fifth force acts between neutrinos. Furthermore, we review this method when applied to standard cosmologies and apply our analysis to minimally coupled quintessence and check past results for early dark energy parametrizations.Comment: 16 pages, 13 figures, published in Physical Review D, minor changes and correction