Ludwig Boltzman, who spent much of his life studying statistical mechanics, died in 1906, by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics. Perhaps it will be wise to approach the subject cautiously.
It's not uncommon for a professor to quote the first paragraph of States of Matter by D.L. Goodstein on the first day of an undergrad statistical mechanics course. Statistical mechanics is an outgrowth of the study of thermodynamics which had become a major intellectual effort attempting to understand heat engines in the 19th century. You can derive the results of thermodynamics from it and it led to much deeper explorations including the beginnings of quantum theory. It's also concerned with entropy. Entropy is at the heart of understanding change. It's deep enough to be tightly connected with why time only goes forward and what cause and effect are. Popular definitions aren't accurate. It isn't the tendency to disorder and it isn't the entropy computer scientists talk about (although Shannon's entropy is an exceptionally important tool for thinking about information).
Unfortunately the fundamental concept of entropy is a bit abstract. xkcd notes a problem common in science and undoubtedly many other places. I'm frequently guilty, but I started to put together a post on the difference between entropy and complexity and why increasing entropy doesn't imply increasing complexity that doesn't involve math. I found myself sketching pictures and wishing they were animated. Then I remembered Sean Carroll did a series of very short YouTube videos with Henry Reich creating the animations as part of Henry's Minute Physics series. They're wonderful!
The third video: Where does complexity come from?, gets at the core of the entropy and complexity and why entropy isn't disorder. It works as a stand-alone, but I recommend watching all five in order. They achieve a good balance of getting the basic concepts across without any danger of anyone committing suicide.
Sean begins with why doesn't time go backwards and covers a fair deal of what the Second Law of Thermodynamics implies. Things like cause and effect, the origin of complexity and even how life can exist.
Some deep and sexy physics without the math.
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