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One of my favorite science demonstrations starts like this. I ask my audience, “How many of you were ever babies?” Most indicate that, yes, they did begin life as infants. Next I ask if they are bigger now than they were then. Again, general assent.
“How did you get that way?” I ask.
“By eating food,” is the answer I eventually get, sometimes not without a little prodding.
Next I hold up two objects. One is an acorn. The other is a tree limb. Once we establish identity and relative size, I ask, “How does this (the acorn) grow into this (the tree limb)? We eat food to grow. What does the tree eat?
Nine times out of nine point one, the adults prod their children – with the wrong answer! They say things like “soil,” or “sunlight.”
I have to be very careful here, because it’s so important to teach gently. And yet the wonder of the answer is so awe-inspiring that I have to deliver it with all the gusto it deserves. A tree, I finally reveal, is made mostly of air.*
In my book The Turtle and the Universe I discuss this amazing fact in the context of global climate change. Trees turn air (actually carbon dioxide in the air) into wood. When wood burns, that carbon dioxide returns to the air, available for the next tree to consume.
When we burn coal, we’re releasing the carbon dioxide stored up not by a single tree over its lifetime, but rather the accumulated CO2 of thousands of trees, built up layer upon layer for thousands or even millions of years. A millennia’s worth of CO2, reversed in a single afternoon.
All this CO2 can have dire effects on sea turtles. Like other turtle eggs, sea turtle eggs depend on the temperature of the sand to become either male or female. As CO2 in the atmosphere drives up temperatures, more and more sea turtles become female, fewer and fewer turn out to be male. If global temperature change results in a imbalance of males and females, sea turtle populations all over the world could come crashing down.
But, according to Dr. Blair Witherington, a sea turtle expert and author, and one of the scientists I interviewed for my book, higher temperatures could have an even more direct effect on sea turtle nests. It could cause them to disappear altogether.
Witherington worries that as temperatures rise, sea levels increase. Humans, loving beaches almost as much as sea turtles do, build expensive structures right on those beaches. As sea levels rise, we will want to protect those investments. One way to protect beachfront property is to harden the beach, building sea walls or other hard structures that keep the rising water out.
But that which keeps out seawater keeps out turtles, as well. With no beaches to lay their eggs, sea turtles, those ancient mariners of an even more ancient sea, will disappear forever.
The Turtle and the Universe is a book of evolution – evolution of stars, evolution of the elements within those stars, evolution of the planet, and the biological evolution of sea turtles and all other living things. Evolution never stops, but one certain way to end a species’ biological evolution is to drive that species to extinction. It would be a sad end for such a distinguished group of animals.
And yet life, and the universe, often find a way. The Turtle and the Universe is a celebration of what’s possible, what this amazingly creative universe has done so far, and what it may still do in the future. It just may be, as we discover in the book, that it’s “turtles all the way down.”
*OK, for those of you more detail-oriented, here’s the story of photosynthesis. Trees and other plants take in CO2 and H2O and turn these raw ingredients into sugar (C6H12O6) and oxygen (O2). The sugar goes into building the tree – leaves, branches, trunk, and roots. The oxygen is released into the air as waste.
Clearly the carbon had to come from carbon dioxide. Just as clearly, the hydrogen had to come from water. What about the oxygen? The obvious choice is that the tree just splits the carbon off the CO2, combines it with water, and voila, there you have sugar.
But that’s not how it works.
In 1941 four scientists named Ruben, Randall, Kamen and Hyde performed careful measurements using a special kind of oxygen called oxygen-18. Oxygen-18 is heavier than ordinary oxygen (called oxygen-16). By giving one set of plants oxygen-18 rich water, and giving another set oxygen-18 rich carbon dioxide, and then looking for oxygen-18 in the plant’s waste gases, the scientists showed that the oxygen given off by plants comes not from carbon dioxide, but rather from water. The absorbed carbon dioxide stays within the plant. In this way, scientists showed that the dry weight of a tree comes chiefly from carbon dioxide gas, not from water. In fact, around 93% of the tree’s dry weight is from carbon dioxide. Trees are made mostly of air!
OK, I have to come back to reductionism. It’s like a sore in your mouth that you just have to keep touching.
I’m reading this book “Darwin Loves You” by George Levine. He at first gives a decent account of reductionism and its power. Then he goes into the most bizarre straw man argument. Honestly, I can’t find an argument against reductionism that isn’t a straw man (or perhaps I’m just not smart enough to see the error of my ways – please help me!)
Levine quotes a philosopher of science named John Dupre. According to Levine, Dupre says, “as objects are united into integrated wholes they acquire new properties.” OK, I’ve no problem with that statement, nor I believe would anyone calling herself a reductionist.
Then Dupre makes the further wild-eyed claim that “these higher-level wholes . . . have causal properties just as real as those of the lower-level wholes out of which they are constructed.”
Wow. So much for reductionism.
I honestly, completely, utterly don’t get it. Someone please help.
No one would ever deny that new properties appear as objects are united. Look around! A single water molecule displays no sense of being wet, but a mole of water molecules suddenly displays wetness. Of course they do (it does?). But surely no one would claim that this “new” property arises from some new law of nature? “Wet” is a property of hydrogen bonds, the fact that the loose hydrogens on every water molecule are attracted to all sorts of other things, resulting in the sticky adhesion that we call wet. That property doesn’t suddenly appear when we put a million, or a billion, or a mole of water molecules together. It was there from the start. That’s all reductionism says.
As for the second point (what little sense I can make of it), once “wet” is established, it can cause lots of other things – presumably things like the squishiness of bread or the slickness of concrete or the stickiness of flour once these things get “wet.” And again, surely no one is claiming a new law of physics for bread dough? Surely squishiness, slickness, and stickiness, all caused by the emergent property of wetness, are best explained by the same hydrogen bonding that makes water wet in the first place?
I understand that as a practical matter reductionism doesn’t always work. Even within physics this is well recognized. My own physics professor used the example of fluid flow. One could try to describe a flowing fluid as a combination of all the positions, all the momenta, and all the physical properties of the flowing particles. But the exercise is hopeless in its complexity. So physicists create a macroscopic object called the body of water (or whatever fluid) and describe it with properties – surface tension, adhesion, cohesion – that “emerge” within the fluid.
This approach has a chance of working. It can’t describe the motion of an individual molecule, but it can capture the motion of the fluid body. And yet surely no one using these simplifications imagines them to be real? Surely everyone recognizes that this is a shortcut, designed to make an impossible problem soluble? Surely no one believes that surface tension, adhesion, and cohesion are anything more than the collective actions of lots and lots of itty bitty molecules?
I know this topic doesn’t have the heat of an evolution vs creation debate. To me, though, the fuzzy thinking I see associated with “holistic science” is a bigger threat than all the young earth creationists you can shove in an ark.
Any thoughts on why this reductionism bashing has become so popular (particularly with, I’m sorry to say, the political left – where I find myself on most every other issue), yet (at least to my undiscerning eye) to be so utterly bereft of substance? Anyone? Bueller?
I’ve heard these words used to describe people like Richard Dawkins, Daniel Dennett, Victor Stenger. Other words, too – like, “confrontational,” “extreme” and, my favorite, “virulent.” How nasty is that?
I am an atheist. I’m also a teacher. Does this make me one of those dangerous people I read about? When I teach, I teach gently. This is both a philosophy and a matter of practicality. While I love to read Dawkins, Dennett, and Stenger, I do believe that there is a tendency to forget, when dealing with the questions these great men deal with every day, what it is to teach.
Teaching is by its very nature risky. You never know what someone else will take from your efforts. When you teach, when you’re committed to it, when it is what you want to do, you have to accept the reality that your learners might take away something completely different from what you intended. It’s their experience, not yours, and you must allow them to wander.
So, for instance, I might show three skulls – a modern chimp, a modern human, and an A. afarensis. I might show that from the front the modern human skull is very different from the other two. The A. afarensis skull looks remarkably chimpanzee like. These observations come from the learners, not from me.
Now we turn the skulls over. The chimpanzee skull has a hole, the foramen magnum, near the back of the skull. The human skull has a similar hole right in the bottom. What about the A. afarensis skull? Where is the hole? In the chimp location, or the human location? The answer, marvelous and clear, is that the A. afarensis hole is in the human location. Why? Like us, A. afarensis walked upright.
From here I can go into a discussion of just how long ago A. afarensis lived. Suppose one minute was a hundred years. Then three minutes ago (more or less) Thomas Jefferson was born (the actual number is two minutes, 40 seconds). On this scale, the Great Pyramid was built 45 minutes ago. A. afarensis lived roughly three weeks ago! And so on, unrolling the wonder of these things.
Here’s my question for all of you. Suppose the learner looks at this timeline, these artifacts of the past, and says, “Where are Adam and Eve?” Obeying my directive to teach gently, yet maintaining my commitment to teach truth, what do I do? Thoughts?
I’ve been researching a story about the sea turtles of Ascension Island. In the center of the South Atlantic, almost exactly halfway between Brazil to the west and West Africa to the East, lies tiny Ascension Island. It is home to one of the most important Green Sea Turtle rookeries in the world. The turtles travel thousands of miles across the Atlantic from their feeding grounds off the coast of Brazil to lay their eggs on this island. Why?
Archie Carr, one of the gods in my pantheon, had a theory. Ascension, you see, is a very young island. Only a million years ago or so, it rose from the depths. The birth of Ascension, as a fiery volcano, is one event in the much larger story of the Mid-Ocean Ridge. The ridge is where new ocean is born. On globes it looks like a stitch down the middle of the Atlantic, perfectly mimicking the coasts of South America and Africa in its undulating motion across the ocean floor. For millions of years, new ocean floor has arisen at the ridge as the Americas and the Old World move further and further apart.
Carr proposed that Greens began nesting, not on Ascension, but on a prot0-Ascension that formed when South America and Africa were still close together. Then, as the seafloor spread and the island moved away from the ridge, it sank. Fortunately for the turtles, about that time a new proto-Ascension formed. This happened again and again. As Brazil and proto-Ascension got further and further away, the distance the turtles had committed themselves to traveling got greater and greater, until we see the modern situation – a monumental migration across half the Atlantic.
It is a beautiful theory. It links together plate tectonics and turtles in a way that is extremely attractive to me. Unfortunately, it isn’t true. Beware the things you want to believe.
Archie Carr had no way of knowing it wasn’t true. He lived just at the very beginning of the time when the tests of his theory could be made with something called mitochondrial DNA.
Mitochondria are amazing. Every one of us has them in our cells. They process our food, “burning” it with the oxygen we breathe. They are the power plants of our cells, the place where all the dirty and dangerous work of combustion happens. They are tough.
If you like dark turkey meat, then you like mitochondria. The dark meat is from the harder-working parts of the turkey, and those parts need lots of mitochondria to process lots of food and oxygen.
The most amazing thing about mitochondria is that we animals didn’t invent them. Instead, we co-opted an already-existing organism to come and live inside us. This may have happened many times. Most of the organs in our cells (organelles, if you cast your mind back to high school biology class) may have originated in this way. Even our own cell nucleus that holds our DNA may have started as an individual organism. It makes you question what “we” really are.
Mitochondria, as once free-living organisms, had DNA. They still do. We can collect that DNA, study it, and learn lots of interesting things.
When I die, my mitochondria will die with me. I have no chance of passing it on. I’m a dead-end street, because I am male.
In each of my daughters’ cells, there are mitochondria. Those mitochondria are copies of my wife’s mitochondria. If I had a son, he, too, would carry my wife’s mitochondria. I myself carry copies of my mother’s mitochondria, and none of my father’s. In other words, mitochondria (through mitochondrial DNA) is an unbroken record from mother to daughter to granddaughter.
Why? Sperm cells contain no mitochondria. Egg cells contain lots. When the sperm cell fertilizes the egg cell, the cell begins dividing, resulting eventually in a baby -be it human, butterfly, or sea turtle. Each cell in the baby contains mitochondria, and they all came from copies of mitochondria found in that original egg cell – the mother’s mitochondria!
So turtle scientists realized they could find out, just by looking at mtDNA, who these Ascension Island turtles really were. What they discovered was amazing.
Mutations build up in DNA all the time. Most of the mutations are harmless, resulting in no effect at all. But still, those mutations are passed on. By mapping the mutations that happen in mtDNA (which is the only way this DNA can change, since it doesn’t recombine during sex), scientists can see how far apart in time any two pieces of mtDNA are. The Ascension Island turtles, though definitely isolated from the other Green Sea Turtles of the Atlantic, had been isolated for only around a million years. That’s just about the age of the current Ascension Island. These turtles never visited proto-Ascension (even if such a place existed). Instead, they began, just a million years ago, to lay eggs on the present Ascension Island.
So Archie Carr’s theory is incorrect. And yet the answer brings on so many new questions. How did a single line of turtles begin one million years ago to lay eggs on faraway, isolated Ascension? Was the population the result of one lost turtle? If so, why were her eggs fertile? Turtles usually mate just offshore of their nesting beaches – certainly that’s how Ascension turtles do it today. And how do the turtles today find their way across these vast distances, again and again, to lay their eggs in this faraway sand?
The amazing thing about science is that for every answer, a thousand new questions spring up. It’s turtles all the way down!
Dancing with the Stars. American Idol. Barack Obama. Lindsay Lohan. These are the things people are interested in.
How carbon forms inside giant, dying stars, and how that carbon comes to know itself, that, not so much. I’m a Jeopardy guy in a Wheel of Fortune World.
OK, now I’ve loaded up this blog entry with search terms that maybe will get me some action. Clever, aren’t I? Or not.
I received a discouraging e-mail from my editor today. It seems that the utter failure of The Turtle and the Universe makes it less likely that any other books I ever write will ever get published. That’s right, everyone in the world who has never published a book has just jumped ahead of me on the list of marketable authors.
Funny that if I write a book bad enough to not get published I can just start over, but if I write a book just bad enough to get published and then do horribly, I am saddled forever. Yes, I shot the albatross.
Oops, that reference will not do well with those readers who got here because they searched for Lindsay Lohan. Sorry.
I started a new book today. That’s one of my favorite things to do. I tend to start many more books than I ever finish.
The book I started reading today is called Darwin Loves You. Unlike most things I read, I’m not reading this one for any particular reason, no article I’m writing, no book I’m researching. Instead, the title caught my eye on a recent trip to the library (to get books for articles I’m writing and books I’m researching).
So I started reading and the author right away talks about the way Darwinism has been viewed by social commentators through history. One in particular, Max Weber, said that a “rational scientific outlook expels the meaning from life.” The author is trying to disprove this notion, and in that I’m already in agreement with him. But even so it is almost shocking for me to read these words actually put to paper. Do people really think this way?
The author talks a lot about mystery, and how it has been suggested again and again that science in general and Darwinism in particular have removed the mystery from life. But it is rare in science for the solution of a mystery to be the end of the story. Instead, the solution leads to both deeper understanding and deeper, more profound mysteries. So when James Clerk Maxwell solved the mystery of light – what is light? It is a vibrating electric and magnetic field – his answer led to deeper questions. Why do electricity and magnetism affect one another as they do? The answer to that question led to Einstein’s special relativity. What is the nature of this electromagnetic wave when it encounters matter? The answer to that led to the photoelectric effect, quantum weirdness, and wave-particle duality.
I wish I could sing this to the world. Mysteries do not become less interesting when they are solved. History shows us that exactly the opposite is true.
BUT (and this is what I really want to say, the point of this blog entry) . . .
even if it were true, even if it were, wouldn’t we have to live our lives as if it weren’t?
Here’s an example. Suppose you buy an old house with many rooms. Each day you explore a new room, discovering uncharted territory. Eventually you come to the last room in the house. Loving adventure and mystery as you do, you decide not to enter that room, to leave it mysterious. You never enter that room, and tell yourself how good you are at preserving mystery.
Aren’t you exactly the same as someone who explores every room in the house? Aren’t you just as bereft of mystery? If you never try to solve the mystery, if you never go into that room, or do anything to find out what’s inside, aren’t you in exactly the same position as one who has no rooms left to explore?
Maybe there’s just something wrong with me. I remember as a kid being fascinated with cryptozoology – you know, Bigfoot, the Loch Ness Monster and such. I wanted to KNOW, are they real? Then I’d talk to adults, or maybe read in a book, expressing the opinion that, “Isn’t it better to have a little mystery in life?” NO! It’s not! If you decide that, then it’s not a mystery any more, because you’re not looking for the answer. You have to look; you have to try to solve a mystery or else it ceases to be mysterious.
The classic example of the piece of information you wouldn’t want to know is the time and place of your own death. This strikes me as particularly stupid. First of all, it’s a ridiculous example. If we did live in a completely deterministic universe, then the fact that I knew this information would be part of that universe, and clearly I would take steps to avoid whatever fate held for me. If it’s a traffic accident, I don’t drive that day. If it’s colon cancer, I get it looked at immediately.
But we don’t live in a completely deterministic universe. Quantum weirdness rules such a universe out. Still, if someone could glean from all the crazy connections of this world that I am most likely to die by X, then I could actively try to change the connections to make X less likely. That information can do nothing but help me.
There is real mystery in the world – What is consciousness? Why do all electrons have the same mass and charge? Why that mass and charge? Why was entropy so incredibly low in the early universe? Will the Cubs ever win the World Series? – but looking for the answers to these mysteries doesn’t sap them of their strength. Rather, the act of looking is what makes them mysteries. Solving them won’t take away the mystery, but only add new and deeper mysteries.
But even if it wouldn’t, we have to live as if it would.
I attended a cultural diversity training today and was introduced to a new idea. At least, it was the first time the idea was presented in such a head-on fashion. It is the idea of posing.
One example given was that of Madonna and her adoption of the Jewish tradition called Kabbalah. Without really experiencing the full Jewish heritage, the argument goes, Madonna is devaluing Kabbalah by using it for her own purposes.
Here’s an article that argues the point.
I disagree. Strongly. And let me just say I never in a million years thought that I would, in my blog about science and a sense of wonder, be defending Madonna, much less Ashton Kutcher.
I’ve tried looking at this from the other side. What if a cherished bit of my own culture (quantum mechanics, say) were usurped by a pretender? Let’s just say his name is Deepak Chopra. Well, yes, that would bother me – it does bother me, in fact. The great thing about science, though, is that it is a self-correcting mechanism. When Chopra makes some bizarre claim and pretends that modern physics backs him up, someone with actual knowledge of science can use Chopra’s distortions as a teaching moment. Maybe even Deepak himself could learn something (though I won’t hold my breath).
But it’s a mistake to claim that Deepak Chopra somehow devalues science in this way. Science is what it is, and you can get it right or get it wrong (as Chopra does). And getting it wrong is nothing more (and nothing less) than a chance to learn.
Bad Astronomy, one of my favorite websites, is a perfect example of this approach. Instead of using the science blunders in movies to denigrate, criticize, or feign offense, Phil Plait uses these blunders as a chance to teach his readers the amazing world of real (ie good) astronomy. Each mistake is a chance to teach, a chance to learn.
OK, back to Madonna, Kabbalah, and offense. I don’t believe Kabbalah belongs to anyone, any more than science belongs to anyone. I believe we all create our own culture, our own universe. I believe we each adopt the parts of culture that work for us, and reject those that do not.
Some of us more or less accept the culture that is handed down to us, by parents, pastors, etc. Others pick and choose from a variety of ideas. But we’re all making choices. As Albus Dumbledore said, “It is the choices we make that show what we truly are, far more than our abilities.” Oops, there’s some of my chosen culture showing through again. So be it.
I have chosen as an important part of my culture an earthwork in Southern Ohio called Serpent Mount. It is a place that helps me remember who I am and how I relate to this universe that made me, for what reason I do not know. I use Serpent Mound in a way that is, I’m certain, very different from the use intended by the Mound’s creators. Do I denigrate it?
Some would certainly think so. I once attended a program on the Octagon Earthworks in Newark, Ohio. I arrived late and had to stand in the back. While a man (a white man) read a story about the Octagon and how it had affected his life, some Native Americans just in front of me made racial comments about the speaker, clearly unhappy that someone from outside their culture would have adopted the Octagon, as I had the Serpent.
The Native Americans are among the most abused people in history. For white Americans to weep over events like the Holocaust or the genocide in the Sudan, yet not recognize the inhumanity of the intentional spread of smallpox and the Trail of Tears is the height of hypocracy. But I, a white American, am here, now, and my choice is to create a culture in which I can live. I don’t believe that Serpent Mound or the Octagon can belong only to Native Americans, any more than the Holocaust can belong only to those who lost loved ones to that horror.
To finish with two “I never thought I’ds” in the same blog post, there’s a pop singer named Anna Nalick who wrote a song that I especially like. The emotional stinger of the song is this:
“2 AM and I’m still awake, writing a song
If I get it all down on paper, it’s no longer inside of me,
Threatening the life it belongs to
And I feel like I’m naked in front of the crowd
Cause these words are my diary, screaming out loud
And I know that you’ll use them, however you want to”
And this is what creation is all about. A song, a story, a mound of dirt, a tradition. They’re our diaries, our screams into the world. If the world hears our screams (and isn’t that why we scream?) we have to accept that the world will use our creations, perhaps in ways we’d not intended.
The creators of Serpent Mound put something into the world, something that, once there, belonged to us all, just as all art and all science belong to all humanity. I have taken Serpent Mound into my own culture, my own universe. If that offends, teach me. I will try to learn.
At COSI we have an exhibit called the Centripetal Generotor. As the device spins, guests are pinned between their own inertia and the inward push of the wall. The friction between the wall and their bodies overcomes the downward pull of gravity, so that even when the floor falls six hundred million nanometers (around two feet), the guests stay stuck to the wall like a radioactive spider.
We recently reopened the Rotor after its winter hiatus. On one of the first days, a young boy described to me his ride. “The floor fell and we stayed stuck to the wall. It was awesome!”
He was clearly excited. “That sounds amazing!” I said. And then, “So why did you stick to the wall?”
“The air pressure pushed against me,” he replied, “and I stuck.”
“Wow, that’s fantastic,” I said, “Have a great rest of your day.”
Misconceptions aren’t limited to young boys on carnival rides, however. Just yesterday I was reading a biography of physicist Lise Meitner for a book I’m writing. I came across this account of her first experience with physics demonstrations.
“Dr. Szarvasy had a real gift for presenting the subject matter of mathematics and physics in an extraordinarily stimulating manner. Sometimes he was able to show us apparatus in the Vienna University Physics Institute, a rarity in private coaching – usually all one was given were figures and diagrams of apparatus. I must confess that I did not always get correct ideas from these, and today it amuses me to think of the astonishment with which I saw certain apparatus for the first time.”
So where do misconceptions come from, and what can we teachers do about them?
I don’t put much stock in most theories of learning. I think the one thing the history of science has shown us is how really, really hard it is to get good data out of nature. Even relatively simple subjects like physics and biology require huge efforts, lots of simplifying assumptions, and repeated trials to get useful results. So when we tackle really complex topics like human psychology, the odds that we’re going to get anything useful are pretty slim. But of the learning theories I’ve encountered, I do at least see some sense in the theories of Piaget – in particular his ideas of assimilation vs. accommodation. And I think that is exactly how we can see misconceptions.
When I see a physics demonstration, I assimilate that demonstration into what I already know of the world and how it works. If I know that heavier things fall faster than lighter things (you’ve seen feathers and bowling balls, haven’t you?), then when the funny guy at COSI drops a tennis ball and a basketball from the same height at the same time and they hit the ground together, well, they must weigh the same, right? I’ve assimilated the demonstration into my view of the world.
If, then, the COSI demonstrator shows that when the tennis ball is on top of the basketball, and they again fall together, the heavier basketball gives a huge push to the lighter tennis ball, I am forced to accommodate my world view to this new piece of information. Wow! Light and heavy things fall at the same speed. That’s amazing!
(OK, to be honest it is probably rare to wipe out a misconception that easily. Most guests probably walk away from the basketball/tennis ball demo with the same set of misconceptions they started with – 0r maybe even more. Remember, even Lise Meitner, who became one of the world’s greatest physicists, developed misconceptions about the demonstrations she saw as an undergraduate.)
So misconceptions are a bad thing, and we as teachers should develop our presentations to combat them. Yes, OK. I agree.
But misconceptions are how we see the world. We each of us create a universe. We populate that universe with our misconceptions. We build our imperfect understanding of the world on our collected experiences. What else could we do?
We are all a big bagful of misconceptions. When we get more sophisticated, we call them “models,” but they’re still misconceptions. The only difference is we know about them now. (Of course I can’t tell you about the misconceptions I have that I don’t know about, sort of by definition really).
For instance, I have a misconception about alpha decay. A radioactive nucleus fires off an alpha particle in one direction and, like the butt of a rifle, the nucleus gets pushed back the other direction by the recoil. I’ve related a microscopic event to a common, everyday occurance, and it makes sense to me.
Only it’s wrong. There’s no mechanism inside a nucleus to fire off an alpha particle. Instead what happens is the alpha suddenly and quite by accident finds itself outside the nucleus through something called quantum tunnelling. Once there, the positive charge of the alpha and the much larger positive charge of the nucleus push against each other, sending the alpha flying one direction and the nucleus recoiling in the other.
Only that’s wrong, too. Alphas aren’t particles, at least not until I observe them. Instead they are waves. The alpha is not in the nucleus, not really, but exists in all parts of the universe. It’s just that the most likely location is inside the nucleus – but just outside is relatively possible, too. And when the wave function collapses, the alpha might be in that relatively possible place that causes the pushing of positive against positive.
Only that’s wrong itself. I’m used to a macroscopic world, where things like refrigerator magnets can repel one another. I know what that feels and looks like, and I imagine it for alpha particles, too. But that’s not right. Instead, virtual photons from the alpha and the nucleus interact, and that interaction produces the positive and negative momentum that sends the alpha and the nucleus flying.
Then there’s the fact that the alpha isn’t really made of two protons and two neutrons, but instead is made of 12 quarks, each of which might actually just be a string, each of which . . .
The point is this: our misconceptions, or models, help us get across the bridge. They help us make sense of the world. When we discover something new, we’re not building on virgin soil. Instead, we’re tearing down the old structure and replacing it with something better, something that matches what we’ve just seen, just heard, just learned a little better. We build the new on top of the old.
When we feel that joy of learning, that amazement at a new and profound idea, we’ve just built a new universe within, constructed from the shattered pieces of the old. It reminds me of my very favorite Emily Dickinson poem:
And then a plank in reason, broke,
And I dropped down and down–
And hit a world at every plunge,
And finished knowing–then–
We need our misconceptions. We need to break through the planks of reason we’ve built. We need to hit new worlds. We need the joy of being wrong.