What Is Entropy?

This is part of my series on Chiara Marletto's groundbreaking book on Constructor Theory "The Science of Can and Can't". In this episode, I do not read from the book but set the scene for newcomers who may not have a physics/engineering/chemistry or perhaps the scientific background to be familiar with some of the concepts introduced in the next chapter from that book. Chapter 6 is called "Work and Heat" and Chiara (along with David Deutsch) are working on a "Constructor Theoretic" approach to thermodynamics: which is a first. I thought it instructive to first look at where we have come from: what the understandings are at the moment with all this, what the history has been and therefore set the scene for what Constructor Theory adds which is new. In this episode I cover the basics (but subtleties!) of the 4 laws of thermodynamics, heat engines, temperature, heat, work, energy, degraded energy and entropy along with some remarks about the philosophy and pedagogy of it all. Readings from physical chemist Peter Atkin's and physicist Paul Davies older and more recent books are made so we get an understanding of the significance many place on this area of physics elevating it to a position alongside quantum theory and general relativity as an essential component of a complete worldview for understanding physical reality as of this moment.