The concept of order arose from thermodynamics, which began as the study of heat in machines like steam engines, to increase their efficiency. It was observed that the total energy was constant, which was the first law of thermodynamics, and that energy always flows from hot to cold, which was the second law. It follows that if our universe is a closed system, it will have a constant energy that constantly disperses.
The second law of thermodynamics then predicts that everything in our universe will disperse, until there is maybe one atom per cubic light year, in a big freeze that will last forever, so:
“… eventually all these over densities will be ironed out and the Universe will be left featureless and lifeless forever, it seems” (Barrow, 2007), p191.
The problem with this prediction is that by the big bang, our universe wasn’t always big. It is now thought that it was once about the size of a tennis ball, then expanded into what it is today. But by thermodynamics, expanding a system requires energy, and blowing up a balloon cools the gas inside it. It follows that our universe isn’t a closed system because it needs energy to expand.
The cooling effect of this expanding is shown by cosmic microwave background, which was once white hot but is now freezing cold. If space is expanding everywhere, every photon now has a slightly longer wavelength than a moment ago, and so less energy than before. Expanding space took its energy and didn’t give it back, so the total energy of the universe must reduce, because expanding takes energy.
Does this then deny the thermodynamic principle of conservation of energy? Not necessarily because if our universe isn’t a closed system, it doesn’t apply. But it does suggest a closer examination of that principle, so on what facts is the principle of conservation of energy based?