The Fabric of the Cosmos the book, such as discussions revolving around classical physics, quantum mechanics, and cosmological physics. Chapter 2, "The Universe and the Bucket", features space as its key point. The question posed by Greene is this: "Is space a human abstraction, or is it a physical entity?" The key thought experiment is a spinning bucket of water, designed to make one think about what creates the force felt inside the bucket when it is spinning. The ideas of Isaac Newton, Ernst Mach, and Gottfried Leibniz on this thought experiment are discussed in detail. Chapter 3, "Relativity and the Absolute", focuses on spacetime.
Interaction information Interaction information The interaction information (McGill 1954), or amounts of information (Hu Kuo Ting, 1962) or co-information (Bell 2003) or information interaction (Licina 2017) is one of several generalizations of the mutual information. In fact, the definition of interaction information is identical to that of multivariate mutual information except for a change in sign in the case of an odd number of random variables except in the work of Licina where information is more like a physical entitiy. Interaction information expresses the amount information (redundancy or synergy) bound up in a set of variables, "beyond" that which is present in