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Interesting Lectures and Seminars

An Introduction to Entropy (School of Social Sciences open course)

Grasping the Phenomenon from a Macro Perspective

Kazuhiro Nishimura
3rd Year Student at the School of Education

“Entropy” is a word that many science students encounter when studying thermodynamics or statistical mechanics in their first and second years. It may sound like a difficult word, but the concept of entropy, “the world is progressing from a disciplined state to one of disorder,” is hidden all around us.

We can give the diversity of living things as an example. By expanding the concept mentioned above, it can be changed to, “as time passes in the world, phenomena that tend to occur stochastically are increasing.” By supposing that living things hand down their genes to their descendants, they should be striving to leave many descendants with various characteristics. That is because, in that way, when there is a cataclysm, there is a higher probability of an unbroken passing on one’s own genes to descendants. As a result of living things repeating this strategy for many years, we can see how today’s diversity came about. This can be said to be the change to a state of disorder (≈diversity) as time passes.

Also, the concept of entropy shows its face in our everyday lives such as the “drinking bird”, which continues to move by using temperature difference around it, ecosystem matter cycles, and the food chain. Professor Hiroshi Wako’s “An Introduction to Entropy” is a lesson that gives those kinds of familiar examples without worrying about exactness using numerical formulas to give an intuitive understanding of entropy. Because it is a 15-week curriculum to substantially deepen understanding, the course also firmly deals with knowledge required to understand entropy such as the law of the conservation of energy, kinetic theory of gas, and the Carnot cycle. This is a lecture where not only students but also liberal arts students who do not like formulas but want to try a science subject, can casually learn the concept of entropy.