Reality Check

The local public library has hundreds of books on religion, but only a handful on atheism. Yesterday I checked out The Atheist’s Guide to Reality, by Alex Rosenberg. At first glance, it seems sensible enough, but problems soon develop.

Rosenberg is absolutely right to insist that science provides the only usable source of information with which to address life’s important questions. He gives himself a quick pop quiz, and gets the answers right: Is there a God? No. What is the purpose of the universe? There is none. What is the meaning of life? Ditto. Does prayer work? Of course not. Is there free will? Not a chance!

He’s also correct, I think, in noting that a big part of the appeal of religion is that the human brain is hard-wired by evolution to relate to stories. Religion is a huge repository of stories — charming, inspiring, or scary. Science is hard for people to grasp because it isn’t a collection of stories.

Where he runs off the rails is in his discussion of science. He doesn’t get his facts straight. Instead, he starts telling stories. Okay, there are no people in the stories, but they’re fables nonetheless.

He accepts the hypothesis of a multiverse as fact, when in fact it’s no more than a vague guess, unsupported by a shred of evidence. He asserts that the entire physical universe is made up of fermions and bosons, even though physicists have no idea what sort(s) of particles dark matter (if it even exists) may be composed of. He dismisses the anthropic principle without troubling to explain that there is a weak anthropic principle (which is quite sensible) and a strong anthropic principle (which is silly).

Or consider this passage: “The physicist’s picture of the universe is the one on which all bets should be placed. The bets are not only that it’s correct as far as it goes, but that it will eventually go all the way and be completely correct. When finished, it will leave nothing out as unexplained from physical first principles (besides those principles themselves).” [Italics in original.] This reminds me of the apocryphal comment, made toward the end of the 19th century, that the Patent Office might as well be closed, because all of the devices that could be invented had already been invented.

As any reader of Scientific American knows, the frontiers of physics are very fuzzy indeed. The essential problem — and it’s not just a practical problem, though it is that; it’s essential — is that the things physicists would like to study are so very small or so very distant in space and time that we’re reaching the limits beyond which it will be impossible to gather raw observational data.

And while we’re on the subject, where exactly did those first principles in physics come from? This is not a trivial question. As Einstein once remarked (or so I’ve read), “The most incomprehensible thing about the universe is that it is comprehensible.” Why exactly should all electrons behave identically? And isn’t that question one that physics should be prepared to investigate?

No, Mr. Rosenberg, physics will never be complete.

His discussion of the Second Law of Thermodynamics is conventional, but flawed. (I’m sure this same flaw is found in physics textbooks. You don’t have to thank me.) Here is how Rosenberg puts it: “The second law tells us that in any region of space left to itself, differences in the amount of energy will very, very, very probably even out until the whole region is uniform in energy.” A few pages later, he says the second law “requires only the extremely probable increase in entropy from moment to moment in a closed system — the whole universe or some isolated part of it.”

There are two related problems with this formulation.

First, there is no such thing as a closed system. You can build an iron box if you like, and pack it full of gas molecules, and observe how they mix. That’s the sort of “closed” system theorists like to talk about. But every second, millions of neutrinos will be zipping straight through that box, as if the iron walls weren’t even there. The iron walls themselves, not having been cooled to absolute zero, will be radiating heat into the interior of the box while simultaneously absorbing heat from whatever is outside the box.

Yes, the Second Law will describe what’s going to happen in the box, unless some outside source of energy intervenes. If an improbable distribution of gas molecules shows up, you look for the outside source of energy. That’s very sensible, but let’s not talk about closed systems, shall we? There are always outside forces acting on a “closed” system.

Second, and more important, we don’t know that the universe as a whole is a closed system. It may be infinite in extent. The part we can observe appears to be finite, though extremely large — but there is an edge past which we can’t see. We don’t know what may be out there past the furthest objects we can observe. If the universe is infinite, then the Second Law becomes meaningless as applied to the universe as a whole, because somewhere out there, there will always be regions of improbably high energy density.

And that’s just the chapter on physics. Having barely started on the chapter about biology and evolution, I stumbled on this howler: “Darwin estimated that at least 300 million years had been required for natural selection to provide the level of adaptation we see around us. (He was off by three orders of magnitude….)” Sorry, Mr. Rosenberg. The difference between 300 million and 3 billion (the actual time span) is only one order of magnitude, not three.

With friends like this, atheism may not need enemies.