Universality Features in Physical Processes and Their Relation to Biomedical Problems

The aim of the article is to show how different physical theories and models can be applied to studying medical and biological systems and processes. To do that, we provide brief reviews of some physical concepts and theories and explain how those models and theories could be useful for solving biomedical problems. Despite the fact that the considered models differ in nature, each is synergetically similar (isomorphic) to some biological system or medical process. This allows us to operate several (sometimes independent) models to investigate one and the same biological system (medical process) from different points of view. Namely, we examine and analyze the relationship between the physical properties and the fractal dimensions of bulk and confined liquid systems by involving the concepts of universality classes and 2d-3d dimensional crossover. Also, we focus on how the dependence of surface tension on size and thermodynamic variables relates to the system's fractal dimension, consider the dependence of the equilibrium order parameter (density or concentration) on the fractal dimension at the liquid-gas interphase boundary (binodal), and obtain a connection between the fractal dimension and the cross-correlation function of the density (concentration) and energy fluctuations. We also discuss the synergetic relationship between nucleation and carcinogenesis, which are the physical and medical processes of new phase formation. Some attention is paid to considering how the fractal dimension concept relates to the neutron-optics investigations of soft matter and shows its biomedical applications. Lastly, we provide the theoretical background and propose models to uncover crossover mechanisms as the system's dimension changes. As well, we consider general concepts that enable the application of methods from phase transitions and critical phenomena to the study of complex biological systems and processes such as cell-to-cell communication or synaptic transmission.