Influence of surrounding matter on the properties of clusters is considered by an approach combining the methods of statistical and quantum mechanics. A cluster is treated as a bound N-particle system and surrounding matter as thermostat. It is shown that, despite arbitrary strong interactions...

A new notion of matrix order indices which relates the matrix norm and its trace is introduced. These indices can be defined for any given matrix. They are especially important for matrices describing many-body systems, equilibrium as well as nonequilibrium, for which the indices present a...

The occurrence of mesoscopic fluctuations in statistical systems implies, from the point of view of dynamical theory, the existence of local instabilities. However, the presence of such fluctuations can make a system, as a whole, more stable from the thermodynamic point of view. Thus, in many...

A model of a ferromagnet is considered, in which there arise mesoscopic fluctuations of paramagnetic phase. The presence of these fluctuations diminishes the magnetization of the ferromagnet, softens the spin-wave spectrum, increases the spin-wave attenuation, shortens the magnon free path,...