DOES ANYBODY REALLY KNOW WHAT TIME IT IS?

I’ve been pondering the nature of time since reading “Slaughterhouse Five” by Kurt Vonnegut in high school. In case you haven’t read the book, it involves a protagonist, Billy Pilgrim, who has become “unstuck in time”, meaning that he bounces between various times in his life and experiences events in real time. While this premise is an interesting science fiction twist in itself Vonnegut uses it to make a statement about the bombing of Dresden Germany during WWII.  More about this later.

Walking around my house the other day I noticed we have clocks everywhere; on the walls, on night stands, on my microwave and oven, on my arm, and in my pocket of all places. The other thing I noticed is that none of them had the same time. I was about to reset all my clocks when I remembered my sainted grandmother Alice. Alice was born in Cornwall at the turn of the 20th century into a world much different than ours. Hers was a world without electrification, where horses were the primary mode of transportation, and people died routinely of diseases we've put behind us. She lived through two world wars and saw humans walk on the moon. Yet through it all her concept of time never changed. To Alice there were only four times, on the hour, quarter past the hour, half past the hour, and quarter to the hour. That was all the accuracy she needed to order her day. There is a simplicity to this that is strangely compelling. Time is such an artificial construct and our communal illusion of accuracy fostered by digital timepieces makes it even more so.  

The discrepancies between timepieces made me think of the term “precision”.  Precision is a mathematical term that speaks to the accuracy of performing a mathematical function on numbers that have a different number of significant digits. The rule is that the result of any mathematical function performed on any series of numbers cannot be more precise than the number with the least significant digits following a decimal point.  For example, let’s multiply 452 times 5.7563. If you are using a calculator that will display fractions to the 10,000^th place you will get the following result:

452 X 5.7563 = 2601.8476

In mathematics this is known as false precision. Since the number 452 does not contain any digits to the right of the decimal place the result of the multiplication cannot have a higher level of accuracy than the number 452.  Therefore, the correct answer to the multiplication problem is:

452 X 5.7563 = 2601.8476 or 2601. 

Note also that you cannot round the .8 up to make the answer 2602 either since that would make the .8 a significant digit in this case.

What does this say about how we measure and perceive time? Can I really say that at this instant it is 4:27:18 in the afternoon? Do the tools I have to measure time perform at that level of accuracy or is this another example of “false precision”? Perhaps more importantly, do I really need to know the time to the hundredth of a second, or the tenth of a second, or the second, or the minute? Or, as I suspect, do I need no more accuracy than that of Alice to give structure to my day?

Now back to Slaughterhouse Five. Slaughterhouse Five led me to question how we experience time. We perceive time as a continuous flow from the past, to the present, to the future. Proof of the linearity of time generally centers around entropy. Since entropy involves the linear decomposition of the universe from a higher energy state to a lower energy state scientists use entropy as an analog for the linearity and directionality of time. But what if, as proposed in Slaughterhouse Five, time isn’t linear? What if our perception of linearity is nothing more than an artificial construct of our human minds?

Silly you say? For evidence of the non-linearity of time we need look no further that Einstein. Einstein’s work demonstrates that time is relative and can be affected by factors such as velocity and mass. How I experience time is different from how you experience time if, for example, if I am traveling at extreme speed relative to you or if I am in close proximity to a large mass and you are not. Elements of the film “Interstellar” depend on this fact. This holds true for us in our physical environment as well. For example, if you and I are walking down the sidewalk at the same velocity we experience time in the same way. 

 

If, however, one of us diverges from this path and walks in a different direction at the same velocity, how we experience time is now different. 

 

Of course, at walking speed this difference is too little for us to notice. So while it may not be possible for use to become “unstuck in time” as was Billy Pilgrim, it certainly is possible for us to experience the passage of time differently.

But what about space-time? You and I occupy the same physical space as countless other entities but at a different point in time. Is it possible to be aware of the entities that occupied the same space as us in the past? I had a “time traveler” moment while on a trip to Rome a few years ago. I was standing in the center of the old Roman Forum and, for a brief moment, I thought I could feel the presence of the thousands of people that occupied this space before me. I sensed the presence to Roman legions parading past the cheering throngs along the Appian Way. I felt the presence of emperors, senators, citizens and slaves going about their daily business around me. Unfortunately, the connection did not last and I was brought back to our space-time by our guide for the day. 

So time remains an enigmatic mystery to me. I find that I continue to ruminate on the nature of time when I find myself gazing at the stars.  And since that day in Rome I’ve tried to tune into the lives of those that went before me, and in doing so break the bonds of space and time.