The Second Law of Thermodynamics is effectively the most fundamental law in all of science apart from, as you may have guessed, the First Law of Thermodynamics. The First Law is pretty simple and fairly intuitive; in essence, it just says that you can’t make something out of nothing. It doesn’t have the profound implications which the Second Law has.
From here on we’ll normally refer to the Second Law of Thermodynamics as simply “2TD”. What it says, in very, very simple terms, is that over time things get worse. This is also stated as things moving into greater chaos, or, more scientifically, as the “Increase of Disorder.” It may well be that in a particular place at a particular time things have become neater, better organised, cleaner or whatever, but overall there is always a decline because energy has inevitably been used. When used, energy degrades, and that degradation has an end point where it can never be used or do anything again. That is a very big deal indeed, since nothing happens without energy being used. This gradual degradation of energy is what tells scientists that the Universe had a definite beginning, and must also have an end, because the energy is running down so that the Universe is, in effect, gradually dying. (Physicists say “Entropy increases”.) This is a process which is quite different from, for example, planetary orbits which appear to be a cyclic, repeatable phenomenon. The degradation of energy is neither cyclic nor repeatable; it’s a one-off, single occurrence. It is, in fact, what gives us Time itself! If you ever wondered if Time was an invention of men to make life more convenient, or alternatively something that has an actual physical reality (as I did in my teens), you now have the answer; Time is a result of 2TD. I did say 2TD was fundamental, didn’t I?
This has implications for Eternity. If Time is limited, Eternity must be something different from Time and infinitely greater than Time. This concept of being Outside of Time gives us the understanding that Eternity is not Time going on, and on, and on, and on; it is actually the absence of Time. You can think of Time as a bubble within Eternity.
This understanding of Eternity and Time is also scientifically satisfying due to the principle that the “Cause is Always Greater than the Effect“. When we try to understand the beginning, or creation, of Time, that principle leads us to conclude that before Time existed there must have been something greater that could have caused it, which logically would be Eternity.
So the first points to take away from an understanding of 2TD are that Eternity is not a long extension of time, but the absence of it; and that time can run alongside or within Eternity. That’s a bit mind-boggling for most people, but follows logically from the science.
The next point to ponder is that Thermodynamics only relates to physical things: matter and energy. Such things are locked within Time. It is therefore a reasonable assumption that anything which existed in eternity/Outside of Time would also be completely outwith the matter/energy/time matrix that Thermodynamics defines. As such, it might also be non-material, and have no requirement for energy. Hold this in mind, and read on.
A related matter here is Information. Wherever we observe a high-level of organisation, which is the opposite of chaos or Disorder, Information is always involved. This is true regardless of whether that organised system is a living thing or an object like a car. The Universe is commonly defined as “All the Matter and Energy that exists.” But the Universe also contains Information; there happens to be bucket-loads of it on DNA! And two things science knows about Information are that, firstly, it only derives from Intelligence; it can never be created by chance. And secondly, that Information is a fundamentally different quantity from Matter or Energy. If it were not, it could be measured with the same units; but it can’t. Matter is measured in grams, Energy is measured in joules; and Information is measured in bytes. We use both matter and energy all the time to store or transmit information, but information has absolutely no fundamental or mathematical connection to either. The only entity it directly connects with is Intelligence. Since there is no Intelligence in the Matter or Energy within the Universe, and since there must be an Intelligent source for the Information on DNA, we should logically expect such a source to exist outside the Universe.
Putting all the points above together leads to a most interesting conclusion: such an information source would be outside the Universe, outside of Time, and non-material. That is exactly how we conceive of God or a spirit, and it is surely not coincidence that the most fundamental science implies the existence of such entities.
The Second Law also provides us with a devastating one-shot kill of Evolution. The many difficulties of Darwinian Evolution actually happening are always explained away by the supposed power of billions of years. But when we understand 2TD we know that billions of years of Time must produce chaos. That would be true even if the starting point were something highly organised. If the starting point is accepted as something as chaotic as a massive, mindless “Big Bang”, then the idea of aeons of Time ever producing anything organised is a double absurdity. Either Darwin’s Theory is wrong, or 2TD is wrong. The Second Law of Thermodynamics is never wrong! (This might just be why you never heard of 2TD in school. Pupils are forced by law to learn Darwin’s theory. Teaching them a physical law that contradicts it might cause doubts.)
