A short post about space, time, and entropy.
We usually talk about the three dimensions of space as a set of three axes labeled X, Y, and Z. These three axes will usually be drawn as three intersecting lines with arrows pointing in all directions. The arrows on both ends of these lines have significance. They represent the fact that there is no directional preference when it comes to the three dimensions of space. We can imagine objects being moved in any direction in space with ease. Time is different. Time is drawn as a line with only one arrow on the end. Time is the one dimension with an asymmetrical directional preference. In other words, time only moves in one direction. This is what physicists call, the arrow of time.
This may seem like just common sense and not at all surprising to you, since this is how we experience time every moment of every day. The past is different from the present, is different from the future. Time passes moment by moment and we cannot easily undo the effects of time passing. For example, if an egg falls off of the counter and breaks on the floor, we can’t reverse time and unbreak that egg. The other three dimensions are different though. Imagine instead of an egg it’s a ball that falls onto the floor. We could easily pick the ball up and put it back on the counter. The ball is back where it started, but we can’t erase the fact that it did fall off the counter and onto the floor. No surprise, right?
It is surprising from a physics perspective though. The fact that this one dimension only moves forward and never backward demands some sort of explanation. Time has an arrow because entropy is increasing in our universe. This is the 2nd Law of thermodynamics. Entropy increases. That’s what makes today different from yesterday. It is why we experience time as a relentless march forward second by second, minute by minute, and year by year. It’s why we know things with clarity about the past but not about the future.
The arrow of time is why the past is unchangeable but the future is not. In other words, there are no do-overs. You can’t choose to have had something different for dinner yesterday, but you can choose what to have for dinner tonight. It may seem like I’m being Captain Obvious here, but I find that I often behave as if this isn’t the case. I know I’m not the only one. I often waste time as if it’s a renewable resource, but it really isn’t. We can’t go back and make different choices about time that has past. We put off making changes and procrastinate pursuing our dreams. There’s plenty of time for all of that later, we say. Is there really though?
Many of us spend our time in the present as if it’s gaining us time in the future, as if we could trade time while we’re young and our kids are around, for money and security and a similar quality and quantity of time later. We can’t. The Arrow Of Time ensures that the time we spend now is gone, while we and everyone around us relentlessly grow older (gain entropy). Bummer, I know.
So many of us abuse our values and the capacity of our bodies now in the present, making a futile attempt to gain freedom later on. Leisure is not the same as freedom. Now is the time to pursue your purpose and live the life you’ve always dreamed of. It takes work to overcome the increasing entropy of the universe, but it is possible. The world around us is full of beautiful examples of life and movement pushing back against the relentless force of entropy and time. Learn from the rivers and the trees. Look to the design of your own body and design the flow of your time.
You can’t change the past but you can choose right now to change the future. Make the effort to design the flow of time in your life toward what matters most to you, then put that design into practice. Declare your purpose and make a stand for your values and priorities. Live the rest of your life full of purpose, on purpose.
Don’t waste time on regret. You can’t change the past. It’s science! You can change the future and everything else about your circumstances. It’s hard work, but the results are worth it.