Time-varying G

Dark Matter, Time-varying G and the Dilaton

The value of the Jordan-Brans-Dicke coupling parameter ! is at present much more tightly bounded below by radar time delay experiments than it is by the predicted time variation of Newton's constant G. We point out the possibility of having a Jordan-Brans-Dicke-type scalar (i.e. a scale-free massless scalar eld or \dilaton") couple with diierent strengths to visible and to conjectured \dark" ma...

Varying G and Other Constants

We review recent progress in the study of varying constants and attempts to explain the observed values of the fundamental physical constants. We describe the variation of G in Newtonian and relativistic scalar-tensor gravity theories. We highlight the behaviour of the isotropic Friedmann solutions and consider some striking features of primordial black hole formation and evaporation if G varie...

FINITE-TIME PASSIVITY OF DISCRETE-TIME T-S FUZZY NEURAL NETWORKS WITH TIME-VARYING DELAYS

This paper focuses on the problem of finite-time boundedness and finite-time passivity of discrete-time T-S fuzzy neural networks with time-varying delays. A suitable Lyapunov--Krasovskii functional(LKF) is established to derive sufficient condition for finite-time passivity of discrete-time T-S fuzzy neural networks. The dynamical system is transformed into a T-S fuzzy model with uncertain par...

Finite time stabilization of time-delay nonlinear systems with uncertainty and time-varying delay

In this paper, the problem of finite-time stability and finite-time stabilization for a specific class of dynamical systems with nonlinear functions in the presence time-varying delay and norm-bounded uncertainty terms is investigated. Nonlinear functions are considered to satisfy the Lipchitz conditions. At first, sufficient conditions to guarantee the finite-time stability for time-delay nonl...

Time-Varying Monetary Policy Reaction Function: The Case of Iran