* The first law of thermodynamics (“the law of conservation of energy”) is that energy cannot be created or destroyed, but it can be changed. In other words, any increase of energy in a system will be equal to the energy put into that system. The second law is that the entropy (or chaos) in a closed system is always increasing. In other words, things don’t just get spontaneously more organized: instead, they fall apart. It’s worth noting that things have gotten more organized on Earth (life has evolved, buildings have been built, etc.), but that’s because Earth isn’t a closed system: it’s powered by the sun. The third law of thermodynamics is that the entropy in a system approaches zero as that system approaches absolute zero: the colder things get, the less entropy you have. When you’re at absolute zero (the coldest possible temperature), all physical motion ceases.