Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Sunday, March 6, 2011

Sending pucks to Bolivia

In yesterday's post, I made the claim that men don't necessarily always think only about sports or sex, that sometimes we think about other things, such as quantum mechanics.  This caused a couple of my female readers to snort with derision, and remark that they've never seen evidence of any such thing.  Just to prove that my statement was true, today's subject is:  quantum mechanics.

Actually, I've been thinking about quantum mechanics a good bit lately, as I've been re-reading Brian Greene's awesome and mind-blowing book The Fabric of the Cosmos, surely one of the most lucid, readable books ever to be written on the subject of how completely freakin' weird the universe is.  No offense to Stephen Hawking, but it beats A Brief History of Time by about a megaparsec.  Even the illustrated version.

I think the thing that strikes me the most, every time I think about such things, is that our perception of the objects in our lives as ordinary misses how strange even everyday objects actually are.  I have no claims to be an expert -- despite the "B. S. Physics" on my diploma, I was a lackluster physics student at best, and most of what I understand about such things has come in the last fifteen years when I really started reading up on the subject -- but what I do understand about it rocks my world.

Here are a few bits of physics weirdness, just to turn your Sunday morning inside-out.  Please keep in mind as you read this that all of this isn't speculation -- it's hard science, experimentally verified over and over.

1)  You never see the present.  Everything you've ever seen is in the past.  Even these words you're reading right now.  You are seeing your computer screen as it was about a billionth of a second ago, when the light left the screen.  The further away something is, the further back in time you're looking.  You see the moon as it was three seconds ago; the sun as it was nine minutes ago; and the closest star (Alpha Centauri) as it was 4.3 years ago.  If Alpha Centauri vanished at 8:00 this morning, you would have no way of knowing it for another 4.3 years.

2)  What the word "now" means isn't the same for everyone.  Einstein did away with that notion.  Not only does relativity predict that individuals traveling relative to each other experience differences in the rate at which time passes, they don't even agree on whether two events were simultaneous or not.  So if I snap my fingers, and at that moment Steve and Joe were the same distance away from me but Steve was moving toward me and Joe was moving away from me, by Steve's clock the snap would have occurred earlier than it would by my clock, and by Joe's clock it would have happened later... and we'd all be correct.  Further, if (by my perspective) Steve and Joe both snapped their fingers simultaneously, neither Steve nor Joe would think those two events were simultaneous at all -- both Steve and Joe would perceive his own snap as coming first!  Three different measurements of the same events -- and once again, all three perceptions would be 100% correct.

3)  Particles aren't hard little billiard balls.  Remember the protons, neutrons, and electrons your chemistry teacher drew on the board, looking like little dots?  Forget that.  They don't exist.  Or at least, that's not the most fundamental reality.  Electrons aren't particles, they're fields of probabilities -- a smear of likelihoods that the electron is in one place or the other.  It's convenient to say that "an electron is here" -- but what this really means is that "here" is the location where the probability field has its highest value.  Now, don't misunderstand this; physicists aren't using "probability" to mean "it's definitely either here or there, and we just happen not to know," in the same sense that I could say that the probability of rolling a four on a fair die is 1/6, and that (even if I can't see the outcome) it either is or isn't a four.  No, it's weirder than that: the electron is the probability field.  If I use a detector, I can pinpoint its location for a moment, but before that moment and after it, the electron really is a spread-out haze of probabilities.  The experimental confirmation of this idea, revolving around the mind-boggling principle called Bell's Inequality (after the brilliant Irish physicist John Bell), showed that until it hits a detector, an electron flying from a source takes all possible paths to get there.  It's as if when Joe Nieuwendyk winds up for a slapshot, the puck travels between his stick and the net by all possible trajectories at the same time, including pathways that went from stick to net via Bolivia, Mars, and the Andromeda Galaxy.  What we see -- that the puck goes straight from stick to net -- is just the average of all of the possible pathways!

(Drat, I slipped back into talking about sports, didn't I?  And I was doing so well, up until that point.)

Again, recall that this is not just some metaphorical way of talking about things; this is the reality of the universe, experimentally confirmed every which way from Sunday.  Even our conventional perception of objects as solid is an illusion -- most of matter is empty space, and the feeling of solidity when you give a passionate kiss to your significant other is just because you're feeling the mutual repulsion between the electrons in your lips and the electrons in your sweetheart's.  Your lips never really touch, as peculiar as that sounds.

(Admit it: after I slipped up with sports, you knew I'd have to work in sex, as well.)

I wish I knew more about this subject (quantum mechanics, not sex).  I find it fascinating that our simplistic understanding through classical physics can be simultaneously so useful and so wildly incomplete.  I, for one, enjoy having my mind blown occasionally, to see that the world is amazing and beautiful and bizarre.  Or, as J. B. S. Haldane once said, "The universe is not only queerer than we imagine; it is queerer than we can imagine."

2 comments:

  1. "You keep using that word. I do not think it means what you think it means."

    I once posed a question in one of my classes, concerning electron clouds. I wondered if there could be a point where one could touch the electron and not touch it, simultaneously. My thinking was that the speed of contact and the acknowledgment of contact made it such that it could be both there and not. I was greeted with stares. Needless to say, this was almost thirty years ago... but it left me with lots of questions. Nice to see you playing along similar lines. I love the ambiguity of empty space. It isn't really empty, it just isn't what we'd planned for.

    Alright, next... let's talk about Dark Matter!

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  2. Every conceivable comment that I could make has been made and you are just seeing the average of them all. Science is awesome.

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