The concept of order arose from thermodynamics, initially the study of work and heat in machines in order to increase the efficiency of steam engines. It was deduced that the total system energy was constant, which became the first law of thermodynamics, and that heat always flows from hot to cold in a closed system, which became the second law. This was generalized to conclude that if the universe is a big machine, it will have a constant energy that always disperses.
The second law of thermodynamics then predicts that everything in our universe will spread out, 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 our universe is expanding, so it wasn’t always big. Scientists now believe that it was once about the size of a tennis ball, then expanded to what it is today. But by thermodynamics, an expanding system absorbs energy, as blowing up a balloon makes the gas inside it cooler. It follows that our universe isn’t a closed system because it needs energy to expand.
For example, if our universe is expanding, every photon now has a slightly longer wavelength than a moment ago so it has less energy than it did before, hence the cosmic microwave background, which was once white hot, is now freezing cold. Expanding space took its energy and didn’t give it back, so the total energy of our universe must be reducing 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?