You are currently browsing the monthly archive for February 2011.
Sometimes I worry that I’ve given a blog entry a title that someone else has used before. This time I think I’m safe.
I saw Black Swan over the weekend and loved it. For me this movie was about losing yourself in your art, and in that way finding that experience of being alive, what Joseph Campbell called “following your bliss.” I think this movie is metaphor. I could argue that all the horrible things Nina the ballerina does or experiences in this film are in her imagination, and I actually think a strong case can be made for it. But I don’t have to, because real or not the events are all just metaphor. The film is about art, and Nina’s discovery of the artist within her. The rest is incidental (yes, even THAT scene!)
Most reviews I’ve read describe the movie as a descent into madness, but they miss the point. Creating art is like madness, but that doesn’t make it madness itself. Art is by its nature the creation of something that wasn’t there before, and is therefore unreal. What you see in your mind, what you imagine, what you are driven to create doesn’t exist until you create it. So of course that act of creation feels crazy. It’s believing in something that doesn’t exist – yet.
Emily Dickinson wrote a poem about what it feels like to give birth to a poem – how painful, tortuous, maddening, and finally liberating it can be. The creative power! The power to give life to something that never existed until it somehow grew within your own mind, sprang from your own soul. Here’s the poem:
I felt a Funeral, in my Brain,
And Mourners to and fro
Kept treading – treading – till it seemed
That Sense was breaking through –
And when they all were seated,
A Service, like a Drum –
Kept beating – beating – till I thought
My Mind was going numb –
And then I heard them lift a Box
And creak across my Soul
With those same Boots of Lead, again,
Then Space – began to toll,
As all the Heavens were a Bell,
And Being, but an Ear,
And I, and Silence, some strange Race
Wrecked, solitary, here –
And then a Plank in Reason, broke,
And I dropped down, and down –
And hit a World, at every plunge,
And Finished knowing – then –
OK, now you’re convinced. I’m out of my mind. This isn’t a poem about writing poetry, it’s a poem about going crazy. That’s what all the critics and all the web sites say. And THEY’RE ALL WRONG! Notice the hints Emily Dickinson leaves us.
Sense was breaking through – not through the floor, that comes later in the poem. This sense is the sense of what this newest, latest poem is going to be about. Dickinson, who wrote in the metaphor of death, had a muse. That muse was a funeral.
Those same boots of lead, again. Several times in the poem, Dickinson indicates that this experience was not once in a lifetime. It has happened to her, in her, again and again.
All the heavens were a bell and being but an ear. She couldn’t help but listen to her muse, the sound in her head was so loud that it consumed her existence, turning her into a receiver only, just an ear.
Her race is with silence, in other words, with death. It isn’t clear in this poem if Dickinson fears death, but it is quite clear that she fears losing to silence, not creating this new poem before she dies. She sees herself wrecked, solitary, unable to complete this thing that is her child, her creation, before silence finally wins.
So far, maybe you’re not convinced. All these things could just as easily apply to madness. Fair enough. But in the final stanza, Dickinson reveals the true nature of this act of creation.
A plank in reason breaks. The final wall, the final block between her and this future place where the poem lives, complete and perfect. With this plank broken, Dickinson falls freely. Again we see that she’s made this journey before, hitting a “world” (a poem) each time she’s taken the plunge. What an amazing metaphor! Writing poetry, creating anything really, is taking a plunge, believing that you’ll hit a world, not knowing, yet taking the leap. The leap . . .
And then the last line, where Dickinson reveals that now, finished, she has a knowledge she lacked before. As painful as it was, she has followed her bliss, she has hit a world, she has finished knowing.
But she’s not done, and maybe never will be. The word –then– followed by Dickinson’s favorite punctuation, the pregnant, anticipatory dash, sends us back to the top of the poem, where the entire process begins again. Lather, rinse, repeat.
This act of creation, this birthing and breathing of life into art, is never pretty. It upsets people. It makes one late for dinner. It soils what we think is proper in ballet, or poetry. Or science. Yes, you knew I had to get there eventually.
Niels Bohr was an artist, as much as he was a scientist. Just like Nina in Black Swan, just like Emily Dickinson with her world plunging, Niels Bohr fought and struggled and convulsed in agonized spasms of pure beauty – and out popped the Bohr model of the atom.
It’s 1911. One of my all-time heroes, Ernest Rutherford, that living bowling ball of enthusiasm and intuition, has just discovered something that cannot be. Rutherford has found that the atom consists of an incredibly dense central nucleus surrounded by bits of orbiting electronic fluff, a little like a miniature solar system. But that is, according to all the science Rutherford or anyone else knows, impossible. Electrons have an electric charge, and whenever objects with an electric charge accelerate, they must radiate away energy. If electrons in an atom did that, all atoms in the universe would collapse to nothing in a tiny fraction of a second.
A tall, shy, and brilliant student of Rutherford’s named Niels Bohr determines to find out why the universe still exists. He plays with an impossible idea. Maybe the electrons don’t fall. No reason, they just don’t. Or rather, they fall, all right, but only an exact, specific amount, and never beyond their lowest energy level. There they stay, never to cease. Why? Mystery . . .
But Bohr’s model, illogical, ugly (and yet so, so beautiful), without any reason behind it, worked. A plank in reason broke (not Max Planck, though I’m sure he wasn’t pleased) and Bohr plunged into a new world. And it worked. When Bohr compared his model to the spectral lines produced by hydrogen, the model worked.
What does that mean, worked? Here’s the picture. A Bohr hydrogen atom has a single electron in orbit. Let’s suppose this atom is energized, perhaps heated, jostled, it doesn’t matter. That means the single electron is orbiting higher than its lowest possible orbit, and that makes the electron unstable. Then, suddenly, the electron falls (a plank in reason breaks?) and out flies a photon. The electron reaches its ground state orbit and stops falling.
Here’s the amazing thing, the thing that Rutherford himself pointed out.
“How,” Rutherford wrote to Bohr, “does an electron decide what frequency it is going to vibrate at when it passes from one stationary state to another? It seems to me that you have to assume that the electron knows beforehand where it is going to stop.”
Indeed. Bohr’s answer, that the transition itself is fundamental, not capable of simpler explanation, was so disturbing that many physicists detested it. Paul Ehrenfest, another physicist and one of Bohr’s closest companions, said, “Bohr’s work . . . has driven me to despair. If this is the way to reach the goal, I must give up doing physics.”
But Bohr had shown the way to the goal. Yes, it is true that the Bohr model was soon eclipsed by better models. But this doesn’t change one bit the amazing accomplishment of this artist doing science. Bohr created something that wasn’t there before, an atom in which electrons behaved like nothing else ever conceived. Bohr hit a world, and finished knowing – then –
Just like Black Swan, just like Dickinson’s funeral in her brain, Bohr’s atom was metaphor. It was creation itself, that act that makes us uniquely human. We are pattern-makers, story tellers. We are the creators. Whether a poem that lasts as long as there are readers, a dance that lasts only moments on the stage, or a model of the atom that holds sway until a better model replaces it, all these creations are metaphor.*
*What’s a metaphor? It’s for cows to eat in!
I have a confession to make. I don’t know squat about nuclear power.
I don’t know if nuclear fission is really safe, if we can deal with nuclear waste in a responsible way, if nuclear fusion can ever be made viable in anything by a hydrogen bomb.
And yet I’m a huge advocate of nuclear power. Why? Because I think it’s freakin’ cool. I think it would be so cool if our society ends up running on the power of atoms first formed in exploded stars from billions of years ago. I think it would be amazing if the power of those same stars were harnessed here on Earth. Every kid learning about our power grid would in turn find out about the secrets of atoms and stars, and the world would be a better place.
I’m also a huge fan of space travel. I am a child of Apollo, born in the late sixties. Some of my earliest memories are watching astronauts on live TV from the Moon. There was a book in my kindergarten classroom that I’ll never forget, a picture book all about Apollo 11, this tiny, spidery lander heading toward a barren landscape, while the faraway white capsule circled overhead. I remember Michael Collins going on Mr. Rogers to talk about why he had to stay behind while his friends walked on the Moon.
I remember putting on my winter coat in the middle of the summer, because I thought it looked like a spacesuit, and pretending to land and walk on the Moon. And I remember eating Push-Ups (best ice cream ever) and then turning the tube, plastic pushing wheel, and plastic stick into a rocketship and flying through the universe in my back yard.
So naturally, when nuclear power and space travel come together, I can’t resist it.
Remember the story of how we know that the helium here on Earth came almost entirely from nuclear decay? It’s because almost every bit of helium we have is helium-4, and helium-4 is made quite easily in alpha decay. The other isotope, helium-3, is almost completely absent from the Earth. But it’s not like that in the Sun.
The Sun makes both helium-3 and helium-4. And it fires both away from itself as part of the solar wind. Atoms of helium-3 streak from the Sun and fly all over the Solar System. Any that impact the Earth are quickly lost, as our atmosphere buffets the speeding particles, slowing them down until they finally drift off and out of the atmosphere.
But the Moon has no atmosphere. Helium-3 that smashes into the Moon has a chance to stay there, especially if it gets trapped in the loose, powdery rocks found on the Moon called regolith.
Scientists estimate that there are over one million tons of helium-3 embedded in the regolith of the Moon, compared to maybe a few hundred pounds of helium-3 to be found anywhere on Earth. So what’s the big deal?
The big deal is this. Nuclear fusion – the technology that’s twenty years away and always will be, as the saying goes – combines deuterium (hydrogen-2) and tritium (hydrogen-3) to make helium-4 and energy. But it also makes lots and lots of neutrons. Neutrons are hard to handle, carry away valuable energy, and also make the surrounding walls radioactive over time. This is nothing like the radioactivity problem of nuclear fission, but it is still a concern.
If we replace tritium with helium-3, the neutron problem disappears. Fusion between deuterium and helium-3 produces helium-4 and a proton, and that proton can be used to make electric current. Fusion with helium-3, so the scientists say, can be 70-80 percent efficient, and eliminate the need to replace radioactive container walls every few years.
So all we have to do is go to the Moon, harvest the helium-3, bring it back to Earth in huge quantities, (oh, and build a working nuclear fusion reactor), and voila! Our energy problems are solved!
Well, you’re right to be skeptical. If it sounds too good to be true, it probably is. But wouldn’t it be so cool? Imagine having the world powered not only by the process the powers the Sun and the stars, a process that requires us to understand matter on its most basic level, but if the fuel for that star-powered world came from space itself? What an incredible world that would be!
And that, my friends, brings us to the end of my story of helium. That’s one element down, only 91 more to go. Wait, didn’t they just discover element 118? Oh, well . . .
Thanks for reading!
As we’ve moved through the story of helium, I’ve found that I know a little less about each topic. We’re now on the next-to-last entry, and its a topic about which I knew close to nothing until I did some research. So if I’ve convinced you through the first ten entries in this series that I know a little about things, this entry will dissuade you of that notion. But here goes, anyway.
Liquid helium is just darn cool. Yes, it’s cold, around 4 degrees C above absolute zero (or 4 Kelvins). But it also is cool in the full of wonder sense, particularly when pure helium-4 reaches a temperature of 2.17 Kelvins. At that temperature, liquid helium-4 becomes something called a “superfluid.”
Here’s a video of what happens when liquid helium reaches 2.17 K. Yes, it’s in Greek. Somehow that makes it even cooler.
When helium-4 reaches 2.17 K and even colder, all the helium atoms in the sample act like a single atom. This explains why the boiling stops; boiling is the process of some atoms (with more energy) escaping and other atoms (with less energy) staying behind. That’s why sweating cools you off; the evaporating sweat carries away heat energy, leaving cooler liquid on your skin.
But if all the atoms in a sample of liquid helium are behaving as a single atom, then none of them can have more energy than any other. They must all have exactly the same energy, and so boiling isn’t possible! Notice in the video how the boiling stops the moment the temperature reaches 2.17 K. When that transition occurs, you are looking at what amounts to a single atom!
But why that temperature? This is the part that blows my mind. There’s this thing called the Heisenberg Uncertainty Principle. It essentially says you can’t have perfect knowledge about two related variables at the same time. In the case of these helium atoms, you can’t know both their position and their momentum. Momentum is related to speed, and speed to temperature. At a particular temperature (you guessed it, 2.17 K), we know a lot about the atoms’ momenta (because it doesn’t have much). As a result of narrowing down the momentum knowledge, our knowledge about the atoms’ positions becomes worse – bad enough that we can’t tell any two atoms apart! Quantum uncertainty means that the atoms overlap!
There’s one further detail here. Only some kinds of atoms can overlap this way. If you remember a couple of posts ago, I wrote about the idea of the Pauli Exclusion Principle, and I hinted that it didn’t always apply. Well, here’s where it doesn’t apply. The reason is number again. Helium-4, with 2 protons, 2 neutrons, and 2 electrons, has 6 particles all with half-integer spin. Big deal, right? It is a big deal, because you can’t add together 6 halves and end up with anything other than a whole. Try it! This means helium-4 always has a whole number of spin. And particles with a whole number of spin don’t obey the Pauli Exclusion Principle!
Helium-3, with only 1 neutron, won’t do what helium-4 does (ok, yes it will, but only at much, much lower temperatures, and for a reason that is thankfully “beyond the scope of this blog entry”), because helium-3 has 5 particles with half-integer spin. But helium-4, with a whole number of spin, behaves in this strange way that electrons can’t. Helium-4 atoms can all be in the same exact state. Crazy!
That might not excite you too much, but maybe this will. If this liquid helium really is, now, a single atom, then maybe it can start to do some of the weird things atoms do. For instance, atoms can interfere with themselves. One of the weirdest things about quantum mechanics is that, because atoms have a wavelength, atoms passed through double slits can create interference patterns just like light beams. Well, quantum mechanics works for atoms, but surely it doesn’t work for things as large as that sample of liquid helium in a test tube? Or does it?
Sir Anthony Leggett, at a lecture I attended a few years ago, suggested an experiment aimed at testing this idea. Once we have this superfluid, macroscopic single atom of liquid helium, let’s try to make it interfere. Do we get interference patterns? If we do, then quantum mechanics applies to the macroscopic world of cats, turtles, and you and me. If we don’t, and we can eliminate any other errors, then there must be other, “hidden” laws of nature that draw a line between microscopic quantum weirdness and the macroscopic world we live in.
As far as I know, the experiment hasn’t been done yet. But other experiments with helium-4, including things like quantized vortices in the spinning fluid and this property of near-zero viscosity, point in one direction. Macroscopic quantum effects are real. Quantum mechanics really does describe our world, not just the world of atoms, but the large world of people and peanut butter sandwiches.
Go back and look at that video again. You’re looking at a single, quantum mechanical “atom” made of billions upon billions of individual helium atoms, each of which has lost its own identity to quantum weirdness. And that is crazy cool!