Does the past exist? I don’t mean in a figurative sense: the stuff of history, (actually memory), relics and artifacts; I mean, does the past have any physical reality? Is the past an actual place that you can go to visit, like in “Back to the Future”, Jules Verne’s “The Time Machine” or my real all time favorite (this is a secret pleasure, because in many respects it’s just a low budget, low-brow sci-fi thriller) “The Terminator”. (I’ve always liked the Terminator because it’s an ‘inverse’ Oedipus story, if you will, where the protagonist comes back in time to become his own father.)
One can argue that the reflected light, the radio waves, the television broadcasts and life forces travel outward at the speed of light forever, waiting for some clever species to resolve them sufficiently to realize that we existed, thus giving credibility to the fact that we were (are) here. That we existed and did important things. But does this constitute a reality, separate and distinct from the present?
Does the past exist?
Any reflective person wishes that they could return to the past to right some perceived personal shortcoming or to change things for the better. Who among us does not wish to return to the past to retract an impulsive or life threatening action? To catch the disease before it becomes malignant? To undo the car wreck? To take back the unkind or thoughtless word? And yet we can’t, can we?
Try as we might, the past is the past, and as much as we wish, in our striving for personal perfection and desire to remake our world, we can’t change the past. What’s done cannot be undone. And despite the world’s historical revisionists (and there seem to be a lot of them in Washington, D.C. lately), the past is what it is, not being changeable or altered except by perception; and it does not seem like a ‘place’.
Of course we fantasize about time travel, but memories are all that we really have. They are what mold us. They make us who we are, and determine how we interpret the world around us. Our acquired wisdom and knowledge (such as it is), our preconditions and histories, are what help us to accomplish the daily tasks and the great things that we, as a species, aspire to do. Let’s face it, it’s not all about existence and the propagation of the species (although that does count for something). The past, as it lives inside our memories, is our most powerful tool. And even though any representation of the past is flawed (because, of course, memories are flawed) and does not have its own true and separate reality, it is a force that affects how we interpret the present. Through memory it has some sort of cosmic substance that gives it a virtual reality that transcends and enhances the present.
Do you suppose that it’s the same for dogs? How about whales? My personal feeling is that any being with a capacity to leverage experience feels this way, and that casts a wide net over living beings.
Does the past exist?
This is not merely a philosophical question, because it has great ramifications to our discussion and, in the end, the structure of the universe. Dr. Steven Hawking spent a lot of time talking about this; much more than I will, I’m sure. Dr. Hawking liked to talk about the arrow of time. He reduced the discussion regarding the direction of time to the molecular level, arguing that there are irreversible processes that show that time can move only forward.
Human experience shows the same thing. Try as you might, the only way to remake a broken egg is to feed it back to the chicken.
Time is a forward arrow, a positive only value that, while connected to the past by its legacy, moves only outward toward the future which it becomes.
So where do all of the old, used up minutes go?
Because of our ‘flat and static earth’ psyche, we tend to perceive time as an independent variable. A wisp of a dimension. A value that we can count and measure, yet can never catch or directly see.
We track time using the relationship between matter and motion. A pendulum clock is a fine example. Pendulum clocks mark time using the known relationship between gravity, mass and rotational motion. Interestingly, in this particular case, the period of the motion is determined not by the weight of the mass at the pendulum’s end, nor by the input energy. The period of the cycle is determined by the length of the pendulum. In this case, and in others as we shall soon see, time is determined and specified by the length of the system.
All of our other clocks work on similar principles. Some use the regular motion of tuning forks. Most these days, rely on the regular vibrations of crystalline structures. This is directly related to resonance, since these crystals vibrate at a resonant frequency that does not change over time and is not affected by gravity, temperature or outward velocity. But such clocking is still reliant on motion. It is the detectable motion of the vibrating crystal that creates the counts that we use to measure time.
For millennia, civilizations could only track time using the motion of the sun and the stars. This really hampered the scientific exploration of physics (among other things), for while a sundial and star charts are effective ways to know what the time of day might be, these tools are particularly ineffective when applied to events that are shorter than a few minutes. Miles per hour could be measured, but feet per second could not.
And when our perception of and our ability to measure time changed, it changed the human outlook in many ways. We are still adjusting to this ‘new’ perception, being the tribal, Earth based sort of beings that we are. But somehow, although we know that time is fleeting, and that measuring time requires motion, we have a confused sensibility about it and still tend to think that time, by itself, is some sort of river that is has a clear flow that may be entered and traversed at will, whose path and boundaries, though ever moving and changing, can be short circuited or cheated to allow us at least a view over the last hill to catch a glimpse of a lost path or a rosy future.
We’ll talk a lot more about time in subsequent chapters, because our perception of and the descriptions that we use for time are at the heart of our geometrical and numerological shortcomings. But for the time being, let’s just say that, as far as we can presently perceive, as far as time is concerned, that there is only the present, no past, no future, that has any physical reality.
And that really distinguishes it from the other, physical, dimensions.