Bad Science and Bad Logic

I wrote an entry a few days ago praising the science reporting in the New York Times. But it seems that for every good pop-science article, there are a dozen bad ones. Take this latest from Discover Magazine as an example.

Science's Alternative to an Intelligent Creator: The Multiverse Theory

Now, I can't speak with authority on whether the scientists quoted in the article are doing bad science (improbable), or whether they're just terrible at communicating their good science (entirely possible), or whether the person who wrote the article simply misrepresented them horribly (most likely in my opinion). But I do know that the article is woefully misleading in both science and logic.

The article discusses the idea of the "multiverse," which is actually an interesting idea to contemplate. It proposes that there are many (possibly an infinite number of) other universes, which may have different physical laws than our own. Some variations of this theory include the proposition that other universes are continually spawning (possibly even from our own, through black holes or other oddities). Now, there are significant and legitimate arguments for the possible existence of a multiverse. The ones described in the article are not among them.

The authors try to tie the multiverse concept to another legitimate scientific idea: that the existence of the universe as we know it is highly improbable. It turns out that if you tweak certain parameters of our fundamental physical laws, life as we know it - along with other elements of the universe as we know it, such as stars, planets, etcetera - could not exist.

In the process, they commit at least two grievous logical errors which not only undermine their argument but could serve to discredit in the minds of the public the real, legitimate scientific theories which they are claiming to promote.

The first sin against logic is basing their argument on a highly-flawed understanding of probability. In essence, the argument is based on the idea that our universe's laws are highly improbable, but would be more probable if there were a bunch more universes out there. This argument is perhaps emotionally compelling, but it is in fact ridiculous.

It is true that when you play a game of chance a lot of times, it is in fact more likely that you will get a specific desired outcome one of the times. If I play the lottery ten million times, it is more likely that I will win one of those times than if I only play it once. This is basic probability, and most people have an intuitive understanding of it.

However (this is a big however), our intuition frequently leads us astray. The fact is that playing the game many times does not increase the odds of getting the specified outcome on any one specific play. Most of us intuitively believe that it does. It's normal, when playing at a slot machine, to think "I've lost so many times, I'm due to win any minute now!" Casinos base their profits on this intuitive misunderstanding. In reality (and casinos' profit margins operate in reality) the odds of winning the next time you play are completely unaltered by the fact that you lost the last 50 times you played.

This seems contradictory - doesn't playing more increase my chances of winning? Yes. But it doesn't increase my chances of winning at any one particular time. The converse is that knowing I've won on one particular play does not increase the probability that I've played a bunch of other times and lost. If I went out tomorrow, bought a lottery ticket, and won, you would not be able to reason from that outcome that I'd probably played the lottery hundreds or thousands or millions of other times.

How does this relate to the Discover article? The fact is that (assuming the laws of the universe arose by chance and not by some mechanism of necessity that we have yet to discover) all we know is that we've played the game at least once and won. We won this one specific time, and this specific universe has stars and planets and galaxies and life in it. If we had not won, we would not be here to argue about it, so it's guaranteed that in any universe where we exist to talk about it, we won. We can not deduce from that outcome how many times the game was played. It could have been played once, ten times, a thousand times, a million times, an infinite number of times, and none of those would alter the probability of this particular specific universe being the winning ticket. The probability of us being here, in this universe, right now, would be completely unchanged and would remain (again, assuming the laws we're talking about are a matter of chance) statistically infinitesmally small.

The second is invoking a false dichotomy. Here's the claim in the article:

Call it a fluke, a mystery, a miracle. Or call it the biggest problem in physics. Short of invoking a benevolent creator, many physicists see only one possible explanation: Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multi­verse. Most of those universes are barren, but some, like ours, have conditions suitable for life.

Now, I don't know if they got this from the physicists. I certainly hope not. It lends credibility to two horrible anti-science arguments: first, that scientists are out to disprove the existence of a deity (and will go to any number of ridiculously absurd and illogical lengths to do so); second, that observations about the universe as we know it can be used as scientific evidence to point to the existence of a deity. Both of these arguments are patently false. Scientists in general are not hostile to religion and are not out to disprove it, and the fact that our universe is improbable is not an argument for the existence of an even more improbable entity.

Even barring the argument I made above from the discussion and assuming that the multiverse is actually a legitimate solution to the problem of the improbability of our universe (if it is a problem), this argument is still a false dichotomy.

First of all, for the same reason that intelligent design is not a solution to the problem of complexity, a divine or intelligent creator is not a solution to the problem of improbability. The creator/designer itself would have to be complex, and is certainly improbable - it would have to exist in the first place (how? we'll never know unless we can detect and measure it) and have a very specific set of characteristics in order to have created this specific universe as we know it.

Secondly, there are other possible solutions to the problem of improbability. Maybe there's something inherent to the process by which our universe formed that made its characteristics inevitable. Maybe there's something inherent to the stuff that comprises it. We don't know, and we're trying to find out. There are many potential solutions to this problem, and it is horribly disingenuous to point to two of them (neither of which is actually a solution) and claim that they're the only two.

Discover, I'm extremely disappointed in you.

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The Reason for Mass: Theory Confirmed!

Physicists ask some very odd questions. It's sort of a longstanding tradition; many of the really interesting discoveries in physical science have been the result of some strange question whose answer seems obvious to most people at the time. The real answer, however, is usually even stranger than the question. The question of what it might be like to travel at the speed of light, for instance, led Einstein to his theories of relativity, which to this day leave most of us with a puzzled feeling as we try to twist our brains in knots in an effort to comprehend it.

They also have a fascination with chopping things up into little tiny bits. We can blame this on the Greeks. Democritus, a fascinating individual, can be credited with the original atomic theory of matter, although it was not until the seventeenth century that this theory began to be accepted and elaborated upon based on observed evidence. Atoms (and their children, molecules) were pretty easy to understand; they were little tiny pieces of known materials. When we chopped up atoms, we got protons, neutrons, and electrons - a little odder, but fairly easily visualized as little spheres creating miniature planetary-system-like objects. The electrons made plenty of sense; they explain electric currents, predict the composition of certain kinds of compounds, and explain certain features of the periodic table. The protons and neutrons fit in with our measurements of atomic masses. So far, so good.

And then it got weird. The masses didn't quite line up; there was some extra mass that couldn't be accounted for using only the masses of the protons and neutrons, and the bigger the atom, the bigger the discrepancy. Some atoms didn't stick together as well as others; they occasionally spat out bits of mass in various ways, in a process known as radioactive decay. Scientists started trying to figure out what made atomic nuclei stick together at all (given that their electromagnetic repulsion ought to make them fly apart), and came up with something called the nuclear "strong force." This implied that there was a whole bunch of energy bound up holding these nuclei together, and that this energy had mass. This was the energy released and the mass lost in radioactive decay and nuclear fission. It was apparently "carried" by a sort of invisible particle called a "gluon." Seriously. Gluon.

And that's where everything came unglued. It turns out the force that holds nuclei together is only a residual effect of the force that holds protons and neutrons themselves together - you see, protons and neutrons are made up of even tinier particles called quarks. And quarks combine in all kinds of different ways besides the well-known protons and neutrons; in fact, there were a bunch of different kinds of quarks besides the ordinary ones in protons and neutrons. There are six different "flavours" of quarks: up, down, top, bottom, strange, and charmed (I told you, physicists are weird!) which combine to make particles. These composite particles were dubbed "bosons." The electron, by the way, is an entirely different sort of animal; it's elementary all by itself, not made up of quarks, and has a whole family of other vaguely-electron-like particles called "leptons." And even worse, all these particles had antiparticles. By the time the current working theory of particle physics, called the Standard Model, was fully-formed, we had a veritable zoo of exotic particles with peculiar names, odd properties, and different masses and behaviors.

This is where physicists started asking the question: Why do these things have the masses they do? The answer seems obvious; stuff has mass because it's made of matter, which has mass because mass is our unit for measuring how much matter we've got. Right? The "why" question seems like circular reasoning. But it's not. The bosons are mostly not exactly made of matter. They're a little bit of matter - the quarks contribute some mass - held together by a lot of energy.

So the "Why do particles have mass?" question is really a two-part problem. The first involves figuring out why quarks themselves have mass; a mechanism for this was postulated in 1963-1964 by several physicists independently, though the theory was eventually named for its last discoverer, a British physicist named Peter Higgs. Essentially, it involves the existence of yet another particle, this one responsible for creating a field which endows other particles with mass as they move through it. This particle has yet to be detected, apparently because it's really big by particle standards (paradoxically, being big makes particles harder to find); it's one of the main things the Large Hadron Collider at CERN in Switzerland is looking for. You may have seen this on the news recently, since it just came on line this fall.

The second part, however, accounts for the vast majority of the mass of bosons: the energy involved in "gluing" them together. And that is the real subject of today's entry. It appears that the theory was correct - the energy of the interactions between quarks and gluons is enough to account for 95% of the mass of protons and neutrons! (remember that we've already established that energy is mass). It gets a lot weirder than I've described here, what with the gluons popping in and out of existence and changing the colour of quarks. I'm not going to get into quark colours; flavours are enough for one day. But check the article out at Discover Magazine! This is really a big deal; we've made a real, significant advancement in particle physics, and it didn't even involve expanding the particle zoo!

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