82 Heat Death

Heat Death

In addition to limiting our efficiency in doing mechanical work, the Second Law drives our bodies toward higher entropy, which means thermal equilibrium with the environment. Unless the environmental temperature happens to be body temperature, reaching thermal equilibrium with the environment means death. Life also requires concentration of chemical potential energy, but due to the the Second Law we tend toward chemical equilibrium, which is not survivable. Concentrations of electrical energy drive your nervous system, but due to the Second Law we are constantly at risk of reaching an internal electrical equilibrium with no electrical activity. Life is a constant battle against various types of equilibrium that would correspond to maximum entropy, but also to death.  Basic metabolism is just the work necessary to fight off our own entropy increases. Doing that work, and even taking in the energy required to do that work,  involves real processes that provide even more opportunities for entropy increases. Even as we manage to prevent the entropy of our bodies from increasing too much,  we cause the entropy of the environment to increase by a greater amount than what we prevented in ourselves. You can’t beat the Second Law of Thermodynamics!  In fact, commonly held prediction for the final fate of the universe is a complete dispersion of all energy in the universe, so the entire universe is at equilibrium and no processes remain which would increase the entropy, and therefore nothing happens all. That fate has been ominously named dubbed heat death, but at least we don’t expect the heat death of the universe to occur for at least 10100 years. [1]

  1. OpenStax, College Physics. OpenStax CNX. Mar 6, 2019 http://cnx.org/contents/031da8d3-b525-429c-80cf-6c8ed997733a@14.78


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