At the heart of England’s idea is the second law of thermodynamics, also known as the law of increasing entropy or the “arrow of time.” Hot
things cool down, gas diffuses through air, eggs scramble but never spontaneously unscramble; in short, energy tends to disperse or spread out as time
progresses. Entropy is a measure of this tendency, quantifying how dispersed the energy is among the particles in a system, and how diffuse those
particles are throughout space. It increases as a simple matter of probability: There are more ways for energy to be spread out than for it to be
concentrated. Thus, as particles in a system move around and interact, they will, through sheer chance, tend to adopt configurations in which the
energy is spread out. Eventually, the system arrives at a state of maximum entropy called “thermodynamic equilibrium,” in which energy is
uniformly distributed. A cup of coffee and the room it sits in become the same temperature, for example. As long as the cup and the room are left
alone, this process is irreversible. The coffee never spontaneously heats up again because the odds are overwhelmingly stacked against so much of the
room’s energy randomly concentrating in its atoms. |