The laws under which we live serve to guard our general safety and protect us from harm by other members of our community. Some have changed over time to reflect differences between our modern society, and that of 1789 when our Constitution was born. We are similarly governed by the laws of physics which, except for an occasional breakthrough discovery, have changed very little. They too are beneficial, though in a different way.
As an example, consider the steam engine. Hero of Alexandria is credited with inventing the first one in 60 AD. Known as an aeolipile, it spun around frantically on steam power, but never had any practical value. Many variations surfaced over the ensuing centuries, until Scottish inventor James Watt made a series of improvements (patented in 1769) and produced a practical steam powered machine. In doing so, he prompted early 19th century physicists to ruminate over heat, energy and work. At the time, most laws were empirical – if the same thing held true through years of repeated trials, it was probably something you could count on.
All of these observations eventually boiled down to the three fundamental laws of thermodynamics (a “zeroth” was added later). The First, which is no less than the foundation for all of modern physics, says in layman’s terms that there is no free lunch, i.e., energy can neither be created nor destroyed in an isolated system. This (along with the Second Law) pretty much rules out perpetual motion machines. The Third Law deals with a temperature of absolute zero – where there is no motion of anything whatsoever – that is impossible to achieve (clearly this one is a bit theoretical). It is the Second Law, however, that is most intriguing. <continue reading>
