And then I wrote… in 2015, I was invited to speak at Starfest, the annual star party of the North York (Ontario) Astronomical Association. I was invited to contribute a short piece for their program booklet; here’s what I sent them… a tease for my lecture, Discarded Worlds: Astronomical ideas that were almost correct…
From the North York web site, a view of the 2011 campgroundsOne of the great strengths of science is that it is able to correct itself. If Dr. Smith makes a mistake, Dr. Jones can point it out and fix it. But what most people don’t appreciate is that the whole progress of science depends on Dr. Smith making the mistake in the first place! That’s what motivates Dr. Jones; that’s what moves the process forward.
In other words, if we are to do science justice, we have to learn how to glory in its mistakes. Good mistakes, that is.
What’s a good mistake? It’s an idea that’s new; it’s an ideal that is reasonable, and pushes our understanding deeper in directions that we might never have thought about before. And it’s an idea that is almost correct. Which is to say, wrong. A mistake. But it’s a mistake that can be tested, and found wanting… especially, found wanting in interesting ways.
The fact of the matter is, science will always be found wanting. A science that is perfect, is a science that is dead.
Science is not about proofs. You find proofs in mathematics; but while science uses math, science is different from math. A mathematical proof is only as good as its assumptions, and the “assumptions” of science, its data, are never perfect – there is always uncertainty, always error. So science’s results are always open to further refinement.
Science doesn’t prove how the universe works. It tries to describe it. But descriptions are not enough; they also have to lead to insights. After all, Ptolemy’s description of planetary motions, in circular epicycles revolving about the Earth, was able to describe the observed positions of planets in our sky every bit as accurately as Copernicus could do. But the Copernican idea of orbits around the Sun led to Kepler’s much better idea of ellipses around the Sun, which were an essential confirmation of Newton’s ideas about gravity and the laws of motion… insights that the Ptolemaic view could never have led to directly.
Yet every step along that way, we see mistakes. We now know that the original Copernicus theory was wrong; he still had planets in circular orbits. And Kepler was wrong; the orbits are not perfect ellipses, because the planets perturb each other. And Newton was wrong; his theory cannot explain the precession of Mercury’s orbit or the decay of the spin rate of pulsars or the other extreme cases where General Relativity is needed. But each step got us closer to a better description of the truth, and no one of them could have occurred without the previous step. Copernicus, after all, could not have done his work without starting with the insights of Ptolemy.
Notice another thing about science. Science describes; and descriptions are usually in the form of analogies… metaphors, similes. The stuff of poetry. Science is not literally true; it is a poetic description of reality.
Thus, Newton can say, “here’s an equation: the acceleration that a falling object experiences, is like the solution to this equation…” Like; but not exactly identical. The equation may not include wind resistance, the baseball’s spin, or the bird that was hit by the infield pop-up. That’s why every theory has to be matched against experiment. That’s why we play the game. And that doesn’t even go into the extreme cases where you need General Relativity to describe the path of an infield bunt in the neighborhood of a black hole.
Example of gravitational lensing known as an Einstein Ring. Credit: NASA & ESA. Acknowledgement: Judy Schmidt (geckzilla.org)Furthermore, I am confident that some future physics will point out where Einstein’s General Relativity is an oversimplification. Some say that that’s already happening with Dark Energy and Dark Matter; the jury’s still out. Stay tuned.
And that points up the most difficult part of doing science. It’s not making the discovery, or even coming up with the clever (if not completely accurate) explanation. It’s knowing when to hold onto your theory in the face of opposition, and knowing when to admit you have to change.
There’s no formula to tell you when to hold and when to quit. Like playing poker, playing science is always a gamble. There’s a wonderful story about Einstein, related in Abraham Pais’ biography: in the 1920s, Einstein was informed of an experiment at Cambridge which appeared to undermine General Relativity. Einstein’s response? The experimenters must have made a mistake. “The Lord is subtle,” said Einstein. “He is not malicious.” (That’s where Pais got the title of his biography, Subtle is the Lord.)
Science is a poetic description of reality. Like poetry, it requires an ill-defined but undeniable sense of “elegance” to be able to recognize a hypothesis that can lead to deeper insights, compared to one is merely a kludge, something that might fit the data in hand but is otherwise sterile, a dead end description of what’s going on.
Finally, notice one essential point of science that we’ve assumed almost without noticing in this whole discussion. For science to have descriptions, metaphors, or mistakes, it must have an audience. You need not only Dr. Smith screwing up, and Dr. Jones correcting her, but also Drs. Patel, Kikwaya, Kurzynski, and Yamamoto to be following the debate and asking the questions that keep both Jones and Smith honest.
Science is a community. The very activity of science, description and insight, requires a whole lot of scientists who are talking to each other, doing the describing and listening to the descriptions, sharing the insights. It’s not enough to see a marvelous sight in your eyepiece; the science is not complete until you have told someone about it.
That’s why we have astronomy clubs; and Starfests.
