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This book illustrates the role of randomness and noise in living organisms. Traditionally, the randomness and noise have been used in understanding signal processing in communications. This book is divided into two sections, the first of which introduces readers to the various types and sources of noise and the constructive role of noise in non-linear dynamics. It also analyses the importance of randomness and noise in a variety of science and engineering applications. In turn, the second section discusses in detail the functional role of noise in biological processes for example, in case of brain function at the level of ion channel, synaptic level and even at cognitive level. These are described in various chapters. One of the challenging issue finding the neuronal correlates of various meditative states is to understand how brain controls various types of noise so as to reach a state of synchronized oscillatory state of the brain corresponding to the state of Samadhi. This is described in details in one chapter called Noise, Coherence and meditation. The concept of noise and the role of randomness in living organism raise lot of controversy for last few decades. This is discussed in a separate chapter. Finally, the epistemic and ontic nature of randomness as discussed in physical science are investigated in the context of living organism.

The study of phase transitions is among the most fascinating fields in physics. Originally limited to transition phenomena in equilibrium systems, this field has outgrown its classical confines during the last two decades. The behavior of far from equilibrium systems has received more and more attention and has been an extremely active and productive subject of research for physicists, chemists and biologists. Their studies have brought about a more unified vision of the laws which govern self-organization processes of physico-chemical and biological sys­ tems. A major achievement has been the extension of the notion of phase transi­ tion to instabilities which occur only in open nonlinear systems. The notion of phase transition has been proven fruitful in apphcation to nonequilibrium ins- bihties known for about eight decades, like certain hydrodynamic instabilities, as well as in the case of the more recently discovered instabilities in quantum optical systems such as the laser, in chemical systems such as the Belousov-Zhabotinskii reaction and in biological systems. Even outside the realm of natural sciences, this notion is now used in economics and sociology. In this monograph we show that the notion of phase transition can be extend­ ed even further. It apphes also to a new class of transition phenomena which occur only in nonequilibrium systems subjected to a randomly fluctuating en­ vironment.