STEM Tuesday: Time is a human construct


4th of July 7

I planned to write about fireworks today.  How do they work?  Of course colors explode because of chemical reactions, but my oh my, the fireworks today are so amazing and they change colors, and little whirligigs shoot out blue then white, and how do they make those smiley faces and hearts pop out?  I turned to my favorite podcast, “Stuff You Should Know,” and soon I found something that reminded me of something that I really wanted to learn more about.

Several years ago, I read an article by a physicist about Time.  That we humans invented it to fit our need to categorize, record, and capture our history and plan our future.  That our nows all happen at the same time, piled on top of each other like a stack of photographs. Well, that’s the intriguing way I remember it.  Josh and Chuck flagged Aeon’s post by Robert Lanza and Bob Berman  as part of their “Best Stuff We’ve Read this Week.”  If you’ve never heard of Josh and Chuck or “Stuff You Should Know,” click here.  You will be so glad you did.

‘If you try to get your hands on time,’ said the physicist Julian Barbour, ‘it’s always slipping through your fingers. People are sure that it’s there but they can’t get hold of it. Now my feeling is that they can’t get hold of it because it isn’t there at all.’

According to John Wheeler, you can change the past.  He set up an experiment to alter a particle of light. As light passed a fork in the experimental apparatus, it had to decide whether to behave like particles or waves. Later (after the light had already passed the fork),a scientist could turn a switch on or off. What the scientist did at that moment retroactively determined what the particle actually did at the fork in the past. Wheeler called this the “delayed-choice experiment.”

The past is just our memory of Nows, the future is a mental construct. None of it can be measured.  Basically, we invented time to cope with the ever-changing Now. The astrophysicist, Julian Barbour’s  invites us to imagine all the

“Nows” as pages of a novel ripped from the book’s spine and tossed randomly onto the floor. Each page is a separate entity existing without time, existing outside of time. Arranging the pages in some special order and moving through them in a step-by-step fashion makes a story unfold. Still, no matter how we arrange the sheets, each page is complete and independent.

That’s about the same analogy I use as our lives as a stack of photographs, each moment existing as a concert of Nows.  Our great-grandmothers “Nows” are our past, a memory, and her future is our “Nows.” Well, not exactly, because we remake the “Nows” of the past through written history, oral tradition, and memories. Our minds imagine a future, because we haven’t yet experienced those “Nows.” Or to put it another way, we haven’t picked up that page of the novel, or turned over that photograph.

Who knew that physics would thread around philosophy until they make one mind-boggling tapestry.

According to Berman and Lanza:

..death does not actually exist. Instead, at death, we reach the imagined border of ourselves, the wooded boundary where, in the old fairy tale, the fox and the hare say goodnight to each other. And if death and time are illusions, so too is the continuity in the connection of nows.

Or as Einstein said at the funeral of a dear friend:

People like us, who believe in physics, know that [tweetthis] the distinction between past, present and future is only a stubbornly persistent illusion.’[/tweetthis]

I’m going to take some time—I mean a bunch of Nows—to wrap my head around this one.  Right in the Now, it seems like science just past the border into mysticism.   There’s lots of room for science and faith to sleep together in the same house.  Don’t you think?

I love this Noir Sunset

Thinking back to the Now that was the beginning of this post, the chemistry magic of fireworks would have been so much easier.