The problem of time and the related issue of rhythm are of a universal and interdisciplinary nature. Twentieth and twentyfirst century science featured a particular problemati-zation of time. I. R. Prigogine labeled the situation «the rediscovery of time», as he noticed the remarkable intensification of interest in the problem of time during the second half of the twentieth century. In classical science, time functioned as an external quantitative parameter, and as such, was fully reversible. The reversibility of time means, in essence, its absence, or the removal of the difference between past, present, and future. In this sense it is possible to talk about a «timeless» scientific worldview, indifferent to the direction of time. Even Einstein retained an essentially «classical» position with respect to this question. In addition to the concept of a «timeless» world, arose the notion of a developing world. Already classical thermodynamics with its notion of entropy, and Darwinism with its idea of evolution, were the first scientific approaches to include a conception of time that had qualitative content, and not a mere quantitative parameter. Here the past, present and future were no longer illusory, but expressions of the fundamental irreversibility in the development of the Universe. The «physics of becoming» was thus born in addition to the existing «physics of being», and an understanding developed of the principal fact that time is synonymous to process and reflects such inevitable characteristics of the world as development and changeability. This understanding allows one to draw an important analogy between the phenomenon of musical time and the time of natural science.