“What an organism feeds on is negative entropy.” Erwin Schrodinger, What is Life (1956)
“The law that entropy always increases holds, I think, the supreme position among the laws of Nature. If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.” — Sir Arthur Stanley Eddington, The Nature of the Physical World (1927)
“The American people are sending a strong message here: We don’t like the implications of this law, and we will not rest until it has been reversed in the courts.” Christian Coalition president Ralph Reed, as reported in the Onion, America’s Finest New’s Source .
What is entropy? Why does life so utterly depend on the ability to extract negative entropy from its environment? What does that mean? What is the secret of really good satire?
To comprehend just a bit why the Entropy Law is so absolutely supreme among the laws of physics consider this. All other physical laws are invariant with respect to time. Newtonian or Classical Mechanics, Einstein’s special theory of relativity, his general theory of relativity, Maxwell’s equations, quantum Mechanics, quantum electro-dynamics, Superstring theory all are equally comfortable with the flow of time in either direction. Only the Entropy Law defines time’s arrow. If we drop a wine glass on a concrete patio it shatters. Time never runs the other way. Shards of glass never come back together and reconstruct the wine glass. The simplest explanation, one of many interpretations of entropy, is a probabilistic one. There is only one organization of the glass shards which forms the glass but an infinite number of random configurations of shards which do not form the glass and all of which are functionally indistinguishable. The glass is ordered and far from thermodynamic equilibrium and has very low entropy. The scattered shards are disordered and have high entropy. Wine glasses shatter in forward time and could only spontaneously reconstruct in negative time. We’ve never observed a glass spontaneously reconstruct. The Entropy Law, the second law of thermodynamics, tells us that we can proceed in one direction from order to disorder in time but we cannot go the other way.
A gallon of gasoline is in a state of low entropy. The concentrated carbon-carbon and hydrogen-carbon bonds store enormous free chemical energy and are far from thermodynamic equilibrium. We can burn these molecules and release the energy and create carbon dioxide and water vapor and heat. What we are doing really is transforming the low entropy of the gasoline into high entropy of scattered carbon dioxide, water vapor and heat. We are using the transformation of the quality of the free energy to move our car.
The energy and matter in the system before and after the transformation is the same and has to be by the first law of thermodynamics which states that energy can neither be created nor destroyed. This is the conservation law. We started with a highly ordered collection of gasoline molecules far from thermodynamic equilibrium and ended up with dispersed molecules and heat scattered throughout the environment. And if we’ve burned a gallon we’ve moved our car 20 or so miles up the road. We’ve done work. Cars like organisms, like society require low entropy.
Even standing still requires low entropy. Bananas rot, cars rust, organisms including people age. Much of the low entropy cost of operating society is simply required for maintenance not growth. GDP got a boost in the wake of Katrina but New Orleans still is not recovered fully. We haven’t fully replaced the wealth we once had. Out bloated military spending, defending as it is, our oil supply, requires vast amounts of low entropy which could otherwise have been spent on growth or simply maintenance of existing wealth. Growth is therefore limited by available low entropy after the requirements of maintenance have been met. If our society is so complex as to require more low entropy than is available growth is impossible.
The arguments which economists raise against prescient books such as Limits to Growth  include: price, technology and substitution. We see that by the Entropy Law, there is no substitute for low entropy. We can replace one source with another but that game is very limited. We can replace wood burning with coal burning and indeed coal has a higher energy density but available coal is limited and not renewable. We have supported less than a billion people burning wood whereas we are supporting seven billion people burning coal and other fossil fuels. We cannot therefore simply go back to wood.
The substitution argument tells us that when oil prices get intolerably high, we will simply substitute some alternate source of low entropy for the low entropy we have been capturing from oil. One problem with this argument is that we’ve invested incredible amounts of low entropy in the development of fossil fuel infrastructure. We did this when oil, from an energy cost perspective, was cheap. Any substitute will require the build out of equivalent infrastructure which right now does not exist . We will have to do this when energy costs are high and low entropy is scarce. And we know there is no substitution for other sources of low entropy. There is no substitution for fresh water, good top soils and nitrogen and phosphorus fertilizer, for example.
Technology may increase our rate of burn of available low entropy and it can improve the efficiency with which we transform available low entropy into useful work but it cannot create available low entropy any more than the wine glass shards can magically reconstruct the wine glass. We see that technology can actually exacerbate limits to growth. Technology cannot violate the second law. And even the most partisan judges cannot repeal it.
Price signals lose their effectiveness when resource limits are reached [4, 5 and 6]. Neo-classical economic hypothesis violate the second law because they assume resources and waste sinks are infinite. At least we know therefore that there is no hope for them.
The point of lowest entropy in the universe was 13.7 billion years ago at the big bang. Black holes represent the highest entropy we are aware of today . Whatever stuff is inside a black hole, and maybe only Steven Hawkins knows, can be rearranged billions upon billions of ways and one still has a black hole. That is thermodynamic equilibrium. You by contrast are a collection of precisely constructed atoms and molecules. Even a very minor deviation, such as the miscoding of a single nucleic acid may portend a cancerous death. You and I are far from thermodynamic equilibrium. We should not take life for granted.
Good satire is almost plausible. :+)
 Donella Meadows, Jorgen Randers, Dennis Meadows, William Behrens, Limits to Growth, 1972 and Limits to Growth, The 30-Year Update, 2004.
 Vaclav Smil, Energy Transformations, 2010.
 Frederick Soddy, Wealth, Virtual Wealth and Debt, 1926.
 Herman Daly, Beyond Growth, 1996.
 Nicholas Georgescu-Roegen, The Entropy Law and the Economic Process, 1971.
 Brian Greene, The Fabric of the Cosmos, 2004.