The only reason why I’m posting this is because I’m writing it in one sitting, late at night, and after some drinks, so keep that in mind. Editing be damned.
So I’ve been doing some thinking about Time, Time with a capital “T”, Time in the sense that physicists talk about Time, and these are my thoughts:
Time as humans think of it is an illusion, resulting from a curious combination of the laws of physics together with the biology of memory. These thoughts that I will discuss are not new; many smart people know of it, and allude to it. Most recently, Brian Greene convinced me that he is clued in, in “Cosmos”, and Neal Stephenson convinced me that he, too, is in the club, in “Anathem”. I come across hints of other indoctrinees occasionally, so I am well aware that I am talking about old ideas. Truthfully, the only reason I have resorted to this sort of introduction, naming names, is so that you are more inclined to give my explanation here a chance. I’m not the only one, is what I’m saying. Other people get it. Just because it doesn’t agree with our sensory observations doesn’t mean you should dismiss it out of hand. Undoubtedly all sorts of physicists and possibly even mystics have a feeling for the notion of Time that I am going put forth here, but the trick is to get some to listen to you. Right now I don’t care, which is why I’m writing. It all just seems so counterintuitive; no one (that I know) will listen to me. Jon thinks I’m silly with these ideas, Gary won’t accept them either, so I wonder whether I’ve gone off the deep end this time.
But here’s the thing: although it feels wrong, as humans, it feels ever so right, as a physicist. When I finally put it together, I had an “ah hah” moment, one of those “of course this is that way it is” feelings, because it explains so much, it makes so many puzzle pieces fit into place, and just like a puzzle suddenly a much bigger picture suddenly clarifies. I’m missing many pieces; much is still very unclear to me; it is likely that I am wrong about quite a few things. However, I feel very strongly that the overall sense of Time as I explain it here is accurate, because it makes so much sense of so much unexplained physics. Just as a Roman may not be able to explain exactly how the sun comes up and the seasons change, and yet nevertheless the explanation that our earth is rotating and we are orbiting around the sun seems so very powerfully helpful in deciphering that mystery, SO TOO I have an abiding sense that these ideas about Time are powerfully explanatory in a way that cannot be wrong–and that even though I may not have a 10th of the answers required to fully enumerate the theory, nevertheless the truth must incorporate as a special condition these very ideas, because they seem to me at this point to be self-evident. When it came together for me, it was a eureka moment, and I said to myself “of course this is the way it is!”.
Okay now that you are sufficiently primed, I will start in with the explaining. I will give you the conclusion, and then I will lead you down the path to reach the conclusion.
We feel that there is a past, present, and future. We feel that there is a single moment of time that is the present, a privileged moment; we feel that there is a portion of the universe that is over and done with, and we call it the Past; and we feel that there is an indeterminate portion of the universe that has not yet happened, that is yet-to-be, and we call this the Future. The Present is a single instant, illuminated like a spotlight, moving forward through history at some pace, that both the Past and the Future are inaccessible, and that the only thing that exists is the Present moment. That is the common view, that is what we feel, what we know of life.
This is an illusion. The history of human thought is filled with examples of species self-centered thought which has proven to be mistaken. We once thought that we were the center of the Earth, around which a disc of flat ocean encircled us. We once thought that we were the center of the universe, around which the Sun and everything else rotated. We once thought that our solar system, even with the Sun at the center, was the center of the larger universe, around which everything rotated. We were once ABSOLUTELY CONVINCED of all of these things, and yet we were wrong, wrong, and wrong. We should be skeptical of what our senses indicate to be de facto truth!
Here’s the truth of this one: Time is an illusion. The passage of Time is an illusion. There is no Past, Present, and Future in the universe; it is a conceit resulting from arrow of Time (Second Law of Thermodynamics) coupled with the nature of human memory.
Let’s revert to kindergarten and use stick figures to draw each second of our life on a piece of 1ft x 1ft clear plexiglass with a sharpie. If you are 32 years, old, go to TAP plastics and purchase a little over 1 billion sheets of thin plexiglass and use a sharpie to draw each second of your life, reduced to the bare essentials of plot (think kindergarten here) on these sheets. Now take all of them and line them up in one continous block of Life. Each sheet represents a single second of your existence.
This stack of plexiglass moments, altogether in one unbroken block, represents the universe as it actually exists. Select one sheet of plexiglass at random, just slip one out, and interrogate the “you” of that particular slice about Past, Present, and Future, and that version of “you” will answer that she happens to reside in the one and only Present, and that the Past is behind her and the Future is ahead of her. Pick another plexiglass page at random, and the answer will be the same. Every single iteration of “you” in that stack will think that they are in the one-and-only Present, and that the Past has already happened and the Future is ahead of them. In that stack of plexiglass moments, no one sheet is more real, or “now”, than any other. They all exist, “simultaneously” if you will (though now we run up against the constraints of our syntax in providing the best imagery, since “simultaneous” is clearly defined within our conventional notion of “time”), and no one moment is more privileged than another. All of our “selves” in that plexiglass block of time are equally real, and every single one of them thinks that she is in the present and “moving through time”, because moving through time is AN ILLUSION.
This illusion of time arises from a combination of the second law of thermodynamics together with the nature of human memory. If you start out with a deck of cards all nicely ordered from 2 to Ace and in their respective suits too, and you shuffle it, you know that when you turn the deck over they will be less organized and more of a mess than they started out as. The principle that drives the evolution of the state of cards is the same principle that results in our sense of time, and you may be disappointed to discover that it arises from mere statistics. The past is an ordered deck of cards, and the laws of physics are the rules for shuffling the cards, and the result is, inexorably, a less organized state of affairs. We no more expect the universe to go backwards in time, as we expect a deck of cards to put itself back in order, and this is the thing: every microscopic, subatomic, interaction in the universe must obey the same statistics, and as a result, the macroscopic, large-scale world that we see seems to evolve in a particular direction. We call this the “arrow of time”, and it results from the “Second Law of Thermodynamics”, which is sometimes stated as “entropy always increases”, and otherwise you can think of as the same rule that means the deck will get more random the more you shuffle it.
Take the three hundred pages of a book, and throw them in the air. When they come down, will they fall in order 1 to 300, just so? Of all the inconceivably enormous ways in which the pages could come down together, there is only one in which they will be all in order, and there is an inconceivably larger number of ways in which they will be out of order.
Our world is comprised of an indescribably, inconceivably enormous number of particles, which comprise everything that we see and know, and all of these particles follow those same laws of statistics. Every moment, the particles are metaphorically “thrown in the air”, and every moment they come down less ordered than they started out. These statistics cause there to be a “forward” and “backward” in time. The statistics define a direction. Though there is no one single Present, Past, and Future, there is a definitely a distinction between moving “forward” and “backward” in time. There is an “arrow of Time”, as physicist refer to it, that results from the simple fact that the world we know of consists of countless billions of particles that are constantly interacting in ways that cause the deck to be more random, as it were.
This forwardness and backwardness, this distinction between forward and backward, this arrow of time, is what gives us the illusion of being in the Present, and as follows:
We can only form memories of the Past. Statistics causes the “backward” direction of Time to be more “knowable” in a way, than the future. In the shuffled deck, you can make memories of it being all in order! You can make memories of the more ordered state, you can make memories of the “past”, but you cannot make memories of the future. This is not because it has “not yet happened” as we usually say! In the plexiglass block of time slices, the “you” from each slice is capable of forming memories of the universe in only one direction–this results from the statistical evolution of the universe!
Memory is biased; memory is what makes you feel like you are moving through time. Memory gives you knowledge of the moment previous, but not the moment to come; memory makes you feel as if you are always on the edge of the Present. Memory separates the universe into two halves: Past and Future, and makes you feel like you are riding right on the line between the two. This is an illusion!
Take yourself above and outside it all, and consider the stack of plexiglass moments of time, every second of your life already laid out. Pull out each stack and interrogate your own self in that moment, and the “you” of that moment will have a memory of their past, and not of their future, and will think that they are in the one and only Present moment. But they all think they are in the Present! In every single slice, they think they are in the one and only privileged Present, because in every single slice, the version of you in that slice has a knowledge and memory of one half of the plexiglass universe, and a total inability to know anything about the other half, and as a result every version of you feels poised in the Present moment. I think I’m repeating myself. If Gary’s reading, I consider it my duty to do so–take that, naysayer! Listen to it a few more times, biotch, until you give it an honest chance!
There will be objections that this is a deterministic universe, and that there is no free will. Some will complain that in my explanation, everything is already determined and nothing we can do will change anything. That is both true–and an inaccurate way of looking at it. The universe IS; all of Time, past and future, is part of it. We can never know the future, determine the future, or change the future, because there is NO FUTURE. It is an illusion. Everything is “already done”, if you will. Every interation of us is simultaneously feeling as real as any other. We are all in existence, “simultaneously” if you must cling to our inferior syntax, and every slice of ourselves “feels” the Present as strongly as any other. And no one single slice can feel the mindset of another; no single slice can have the knowledge or the perspective of their own iteration in a different slice–which is exactly why all of us feel like the very only privileged one.
I’m done for now. I’ve started to write something about this many times, and always give up because I sound a bit mad, and I don’t have all the answers, and I haven’t had enough to drink to start blabbing on as I have been here. In another installation I’ll try to convince you that this viewpoint of Time, i.e. that looking at Time in this way, makes sense of many other generally counterintuitive aspects of physics (and thereby hopefully provide some more compelling evidence than just a good explanation). It makes clear sense of special relativity, and it may even be able to resolve the difficulty that all sensible people have with quantum mechanics. I’m not yet sure, but I don’t think that this view of Time is the same as Einstein’s hidden variable interpretation, which has been conclusively routed by Bell’s inequality (i.e. EPR paradox and the victorious copenhagen interpretation). I feel somehow that, because this idea showcases the symmetry of time on the non-statistical scale, the contradictory aspects of some experiments in QM may make intuitive sense. What if the parting pair of entangled particles must obey the rules of the future as equally as the past? Is it not sufficient to explain the faster-than-light communication between them? Perhaps not. Smarter people than me have been thinking about this for a long time, so I expect that Bell’s inequality will limit my views of Time in some fashion–we cannot avoid the randomness in any case, but I’ll finish with this: it can only help us to start thinking of Time as it really is, and dispensing with this illusion we have of a privileged Present moment.