Uncertainty

The pace of farm life slows down this time of year. There’s still plenty to do, but things aren’t as urgent. And by 5:30 or so it’s too dark outside to do anything, which leaves me a lot more time for reading now.

It’s nice to have time for books again. I’m gradually reducing the big stack that I accumulated over the summer.

I’ve just finished David Lindley’s Uncertainty, a fascinating history of the development of quantum mechanics during the early part of the last century. Until scientists like Bohr and Heisenberg blew up classical physics, scientists believed that all effects had causes and that with perfect information about the present, one could precisely predict the future. But the quantum physicists proved that at the subatomic level reality is unpredictable. Things happen for no reason. At the quantum level we can determine only the probability of an event. There is an inherent element of chance, unpredictability, uncertainty. It seems that subatomic particles have personalities and they don’t obey the classical rules. So even though at the visible level things seem orderly and predictable, when we drill all the way down we find arbitrariness.

Of course these discoveries have been disconcerting to those who don’t like the idea that uncaused events occur. Einstein went to his grave refusing to believe it could be true.

But I kind of like knowing that all of nature, at its core, is a cloud of uncertainty. As Jonathan Fields says (in an entirely different context), “There is no such thing as possibility, without uncertainty.” I’ve never accepted the idea that we are just machines. Maybe nothing is. Maybe all of the things we take for granted as “certain” are in reality just very highly probable. (Of course I do appreciate the fact that classical physics still works just fine once we leave the subatomic world. It’s nice to be able to count on gravity, for example).

At the end of the book the author makes a fascinating observation, one new to me, and it is worth quoting:

There can be no going back to the old days of absolute determinism, when, as the Marquis de Laplace hoped, knowledge of the present would bring complete knowledge of  the past and the future.

Cosmically speaking, that may be a good thing. The Laplacian universe can have no moment of birth, because any set of physical conditions must arise, logically and inevitably, from some prior situation, and so on ad infinitum. Nothing uncaused can happen

But the quantum universe is different. Ever since Marie Curie wondered at the spontaneity of radioactive decay, ever since Rutherford asked Bohr what made an electron jump from one place in an atom to another, the recognition has grown that quantum events happen, ultimately, for no reason at all.

So we reach an impasse. Classical physics cannot say why the universe happened, because nothing can happen except that prior events caused it to happen. Quantum physics cannot say why the universe happened, except to say that it did, spontaneously, as a matter of probability rather than certainty….We come to a paradox that Bohr would have loved: it’s only through an initial, inexplicable act of quantum mechanical uncertainty that our universe came into being, setting off a chain of events that led to our appearance on the scene, wondering what initial impetus led to our existence.

Of course the philosophical (and theological) implications of that are obvious. And that is enough fodder to keep a nerdy farmer’s brain itching for a long time.

Advertisements

14 comments on “Uncertainty

  1. nebraskadave says:

    Bill, ha, some light reading before bed time. 🙂 I read “Mother Earth News” and “Grit” magazine articles with some books about new gardening techniques before bed. During the Winter months more videos about garden allotments and such keep me entertained. Quantum any thing is …. well …. just too quantum for me. You continue to amaze me with the depth of your interests while living the simple homestead life. There definitely is a randomness about nature that can only be explained by divine intervention. Animal and plant species have come and gone but were in existence at just the right time. Scientists have tried to explain the explainable for thousands of years. In this world of exploding knowledge, some things are still a mystery. Hence, we have quantum physics and quantum mechanics to try to make some sense out of the mysteries of the universe. As for me, I’m just a guy likes to dig in the dirt, take care of family, and reminisce about the good old days.

    Have a great quantum uncertainty day.

    Like

    • Bill says:

      I haven’t seen a Grit magazine in a long time, but I do love my Mother Earth News. I’ve never really gotten into watching the videos though. Out here in internet wasteland, it’s hard to get them to load.

      I’m kind of a science geek, as long as there’s not too much complicated math involved. 🙂

      Liked by 1 person

  2. avwalters says:

    Maybe, just maybe, in that gap between Newtonian physics and quantum, that uncertainty is the essence of hope.

    Liked by 1 person

  3. Joanna says:

    And I thought I was bad with the academic perusing. 😀

    Like

  4. EllaDee says:

    Fascinating… and makes perfect sense to me. I’m a fan of wonder, possibilities, uncertainties, magic, unbelievables, faith, belief and the changeability of knowledge.

    Like

    • Bill says:

      And isn’t it fun to know that the material universe, at its very base, operates unpredictably, on chance, possibility and randomness? The idea that with enough data we could derive equations that would explain everything now seems hopelessly old-fashioned.

      Liked by 2 people

  5. Laurie Graves says:

    Yay for nerdy farmers ;)! The passage you quoted brought to mind “The Hobbit,” and how Bilbo by chance stumbled upon the ring and set in motion totally unpredictable results. A fantasy story, of course, is not proof of real life. Yet perhaps Tolkien had his own point to make.

    Like

  6. Schrodinger’s cat lives! –Curt

    Like

    • Bill says:

      Ah, but does it? We can’t know without looking in the box can we? 🙂

      Interestingly, I read in the book that Schrodinger got the idea for his famous cat from Einstein, who made the same point but with a different illustration. Einstein imagined a bomb rigged to explode upon the occurrence of some unpredictable quantum event. How can a bomb be both exploded and unexploded at the same time, he asked. Schrodinger recast the illustration with an unfortunate cat. Much more memorable. 🙂

      Like

      • So, we have to return to our basic positive nature and assume poor kitty continues to exist with an ample supply of mice, water, catnip and all of the other things that make kitty happy. If it is going to either exist or not-exist, it seems only fair that it lives with all of the accouterments. 🙂 –Curt

        Liked by 1 person

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s