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I live in Ohio, a high-stakes testing state. The deal is, if a school’s students perform consistently poorly on the Ohio Achievement Tests (OATs), eventually all the teachers and school’s principal get reassigned and the school starts again from scratch.
Pretty high stakes, for the teachers who try to build a career and a life, and for students who find their school turned upside-down.
I’m by no means a fan of what happens in most classrooms, but I do feel for teachers forced to teach to a test. And as a father of two children in these high-stakes schools, I definitely feel for the kids who’ve had any remaining joy sucked out of the educational process. According to the politicians, these schools are teaching so poorly that they deserve to be punished.
But are they teaching poorly? There’s a new study on the Ohio Achievement Tests that was reported in the local newspaper on Sunday. Here’s an online version. In short, it says that the OATs map nothing nearly so well as the socio-economic situation of the students in a school. We’re punishing students for coming from poor families, and we’re punishing teachers for working in poor districts. We’re hurting most the very kids who most need our help. And this we call “no child left behind.”
Isn’t it amazing how easy it is to fool yourself? Notice where the criticism of this study is coming from. Ohio Department of Education officials have an awful lot invested in the current high-stakes testing environment, so any evidence against it it is discounted or ignored. Teaching to the test is compared to coaching to win. But if the game is invalid, what’s the point of winning it? What have you really taught? “Fairness and sensitivity committees” review the questions. But if the data shows that the tests still map to socio-economic status, even after the review, then clearly the review process was a failure, right? Beware the things you want to believe. The easiest person to fool is yourself.
Ironic it is that if education did what it is supposed to do, then those in charge at ODE would understand that they can’t ignore scientific data simply because they don’t like the results.
I went to a lecture by Sir Anthony Leggett at Otterbein University tonight. His question was this: where does the weirdness of quantum mechanics go in the real world?
He started by describing the double-slit experiment as the classic example of quantum weirdness. I actually prefer Richard Feynman’s much simpler example of quantum weirdness in everyday life. Aim a photon gun at a pane of glass. To make it easy, suppose there is a 50% chance of the photon getting through. If your photon gun shoots one photon at a time, say, one every hour, then you can capture each photon event. Either the photon gets through or it bounces off.
Here’s the problem. Each photon is absolutely identical. Why does one get through and the other not? There’s no reason, and no way of predicting which photon gets through and which doesn’t. According to quantum mechanics, until someone observes the photon it has neither passed through nor bounced off. Experiments of similar situations confirm that the photon really is in this weird middle world.
In the world of big things, we never see such strange behavior. Why? The traditional answer is that the real world is so complicated that quantum effects get smeared out. Dr. Leggett sneered at this answer, saying that just because evidence disappears (for instance, an axe used in a crime) doesn’t make the perpetrator any less guilty. In a bit of a twisted argument, Dr. Leggett said then that just because quantum effects aren’t visible in the world of big things is no proof that quantum effects are simply hidden by messiness.
OK, that’s a little twisted, so let’s try it again. Dr. Leggett is hoping to do experiments with several billion helium atoms. These several billion helium atoms could potentially display quantum behavior. Dr. Leggett says one of three things might happen.
First, the experiment might not work. Quantum effects are hidden by the noise, just as conventional wisdom says happens for any other event in the world of big things.
Second, the experiment might show quantum effects. If so, it would be the largest system yet to show quantum weirdness, bringing quantum weirdness one step closer to the world of people, turtles, and peanut butter sandwiches. That would be an achievement.
Third, the result Dr. Leggett hinted strongly that he was hoping for, the experiment might show no quantum effects, yet clearly not be swamped by noise. If this happens, Dr. Leggett says, then reductionism is dead. There are additional laws of physics, not just fuzzy smeariness resulting from complexity, that prevent quantum weirdness from showing up in the macroscopic world. There are laws of physics, in other words, that work only when lots of things are brought together. One hundred monkeys.
Dr. Leggett is excited by this idea. I hope it is the wrong idea. Why do I hope that? Surely new laws of physics, new things to discover, opens an exciting new world, much like the world that suddenly opened to scientists at the beginning of the last century as quantum mechanics, radioactivity, and relativity burst into the world.
Maybe I’m just too old. But I would mourn the loss of reductionism. Reductionism gets a bad rap, because people feel constrained by it. But reductionist ideas have been so very powerful. Atomic theory in physics and chemistry. Evolution in biology. Plate tectonics in geology. Big Bang cosmology in astronomy. These great ideas, these “theories of everything” have been so useful in all these fields.
Also, to me, reductionism is the essence of understanding. To understand something is to see its inner workings in terms of simpler, more fundamental somethings. I understand an engine when I reduce its parts to the laws of thermodynamics and motion. I understand the gas laws when I reduce them to the behavior of atoms. If, instead, the gas laws only made sense when you considered the collective, emergent behavior of 100 or 200 or 10 million atoms, we lose an elegant piece of the explainable universe.
Emergent properties are certainly real things (Why does water feel wet?), but my hunch, and my hope, I have to admit, is that as we understand more and more about emergent properties we’ll see that they “emerge” directly from the fundamental laws underlying everything, and not, as the non-reductionists hope, from new laws that only kick in as complexity grows.
The great thing about science is, someday we’ll know!
After many delays, finally I watched Episode Five of Cosmos: Blues for a Red Planet. This was one of my favorites back in 1980. I loved the HG Wells passage, the lesson about Percival Lowell and how easy it is to believe the things you want to be true, and especially the simulated flight over Olympus Mons and through the Vallis Marinaris.
But what struck me on this viewing was the excitement of the Viking landings on Mars, and how Sagan re-captured that excitement. I remember well that first landing day, seeing pictures of Mars with rocks, a pink sky, that distant horizon. It was a golden time – there were the Viking landings, the Voyager encounters with Jupiter and Saturn, and the Russian Venera probes to Venus. And of course there was Cosmos.
It seemed to me that I was growing up in the golden age of science – space science, anyway, and I’m not sure I made much of a distinction. There were so many amazing discoveries, and so many more yet to come. I looked forward to the future missions to the planets, to the return of Halley’s comet, so many other things. And I started to wonder what happened to all that excitement? Where is it today?
Then I took a look at some of the recent events. Huygens landed on Titan. The Mars Polar Lander touched down successfully, even as Spirit and Opportunity still explore the hills and dunes of Barsoom. The LHC just started up (and had a glitch, but still should give some amazing results soon). LIGO is even now listening to space for the first faint gravity wave whispers. Scientists have discovered that universal expansion is not slowing, as expected, but is accelerating. We’re hot on the heels of dark matter and even dark energy. We have new photos of Mercury. And on and on. THIS is the golden age!
So why is science news these days so often glum and depressing? Here, I think, are some of the problems:
1) Everybody’s worried about the economy, the environment, the future of the planet and our species. How is science going to save us from ourselves? Those stories are of course important, but they’re pretty weak on wonder. You can only take so much gloom and doom.
2) There’s a huge push to be practical. What good is space exploration, LHC, etc? I think it relates to this obsession we have right now with measurable outcomes for everything. Whatever happened to passionate people studying what they’re passionate about? Who will champion that? Do what you love, and the money will follow.
3) There’s too much confusion between science and technology. Sure cancer drugs, the power grid, and improved solar panels are important, but they don’t get me closer to understanding the big questions. Those are the questions I’m after.
Why is there something rather than nothing? Why do electrons have just the charge they have, no more, no less, and always exactly the same as every other electron? What is causing these intense gamma ray bursts from deep space? Is it black holes, quasars, or something else we don’t understand at all? Why was the early universe so incredibly ordered?
These are all questions we have a chance of answering in the near future. THIS is the golden age of science!
I was driving to work a couple of mornings ago and following a white car. It suddenly occurred to me that I wasn’t following a white car at all. Rather, I was following a car that reflected all the colors of the rainbow. If I could analyze each individual photon entering my eyes, I would discover not a single white photon in the bunch. Yet knowing this reality had no effect whatsoever on my perception of the car. No matter how hard I looked, all I saw was white.
That got me thinking about light and vision and how we see. Even when surrounded by white light, white isn’t really there. Instead we’re surrounded by individual photons, all different colors, none of them white. But of course “color” isn’t really there, either. There’s absolutely no difference between a red photon and a green photon except for a tiny difference in frequency (energy, wavelength, whatever you want to measure). The greenness or the redness doesn’t materialize until the photon enters your eye – and then it’s not a photon anymore!
And yet again, knowing that the greenness of a leaf or the redness of an apple doesn’t really exist until the light enters my eye doesn’t change the perception. Even more, just because an object like an apple looks red doesn’t mean it’s reflecting red light. It might be reflecting many colors which just add up to red, in the same way the white car is just a combination of colors that add up to white.
Trees grow red apples to make them more conspicuous to animals who eat fruit. This makes it more likely that the tree’s seeds will be spread. But apple trees have no eyes. Amazingly, they still produce the right chemicals to make the apple red. Pretty amazing. It’s like us being born with a dog whistle and knowing exactly how to use it.
Then the car turned and I went to work.
One of my greatest fears growing up (OK, I was a weird kid) was that I was getting opposing sides of a story without knowing it. I read a lot of different kinds of science books. I read books about evolution, I read books about astronomy, I read books about physics, chemistry, dinosaurs, nuclear power, all sorts of animals and ecosystems, ancient humans, and on and on. The books I was most attracted to were the ones in which I felt the author was talking right to me, as if we were in the same room and this was a private lesson meant just for me.
I always worried, though. What if this author’s voice and that author’s voice weren’t really the same voice at all? What if author A started with one set of assumptions (the Earth is 4.6 billion years old, for instance), but author B started with a completely different set (no, the Earth’s only 6 thousand years old, silly. Everyone knows that). Which voice of authority should I believe? Could it be that biologists had this beautiful story all laid out, but behind the scenes physicists were all shaking their heads and wondering how anyone could believe such baloney?
Fortunately, Isaac Asimov, Carl Sagan, and others showed me that modern science really is one story. There might be disagreements within fields, but everyone agrees on the basic framework. It wasn’t always so.
I wonder how I would have reacted to the disagreement between physics (led by William Thomson) and biology (led by Darwin) had I been reading around 1900. Darwin said the Earth had to be hundreds of millions, maybe even billions, of years old to give evolution time to work. Thomson said the Earth could be no more than a few million years old, due to its internal temperature. Probably I’d have sided with the physicists. They had the numbers, after all.
But the physicists were wrong. What Thomson didn’t know – couldn’t have known – was that there was a hidden heat source in the Earth, radioactive decay. I’ve always thought it was beautiful that not only did radioactive decay give Darwin the billions of years his theory needed, it also gave a yardstick for measuring those billions of years.
Of all the beautiful things about modern science, I think the most beautiful must be the way it all hangs together so elegantly. In another hundred years, will science still work this way? Or will our ideas seem as quaint and out of place as the disagreement between Darwin and Thomson?
I was listening to a book on cd recently when the speaker made an interesting claim. He claimed that “what is a scientific question” can change over time. His example was that once the question of the origin of the universe was not a scientific question, because we had no evidence for such a beginning. Then Edwin Hubble discovered the expansion of the universe, and suddenly we could see that looking out into the universe pointed us toward a time when the universe was very different. Suddenly the origin of the universe was a scientific question.
I started thinking of other examples. The classic one, that I wrote about before, is the composition of the stars question. Once we had no way of knowing, so the question was not a scientific one. Then we discovered that we could read the composition of a star in its spectrum. Once we couldn’t know the true age of certain fossils, only their relative ages. Then we discovered radiometric dating, and suddenly dinosaurs and other old things had a numeric age.
I’m wondering if it ever goes the other way. Once we thought the universe was all clockwork; if you knew the initial conditions exactly, you could exactly predict the future. Then Heisenberg and the uncertainty principle came along and knocked that idea out. But is that really a scientific question becoming a non-scientific one? I don’t think so, because the idea was never a real prediction about the future, just a theoretical idealization. We never could know the initial conditions so perfectly, anyway.
So I’m wondering. Is it true that the “scientific question bubble” always gets bigger, and never smaller? Does a question ever go from a scientific one to a non-scientific one?