Collective phenomena in strongly nonequilibrium systems interacting with electromagnetic field are considered. Such systems are described by complicated non-linear differential or integro–differential equations. The aim of this review is to show that many nonlinear collective phenomena can be successfully treated by a recently developed method called the Scale Separation Approach whose name is ...

Much of interesting complex biological behaviour arises from collective properties. Important information about lies in the time and space structure fluctuations around average properties, two-point correlation functions are a fundamental tool to study these fluctuations. We give self-contained presentation definitions techniques for computation aimed at providing students researchers outside f...

We consider nonlinear photoprocesses in a bichromophore, that is, in a molecule consisting of two chromophoric groups (monomers). The phenomena considered include stepwise excitation and collective processes (summation of the excitation energy of two monomers in one of them and nonlinear quenching), as well as energy transfer between the monomers. A system of kinetic (balance) equations describ...

A wide range of natural and engineered phenomena rely on large networks of interacting units to reach a dynamical consensus state where the system collectively operates. Here we study the dynamics of self-organizing systems and show that for generic directed networks the collective frequency of the ensemble is not the same as the mean of the individuals' natural frequencies. Specifically, we sh...