Why the Age of the Earth Matters

Senator Marco Rubio got some publicity of a kind he probably didn't want this week with the publication of an interview in GQ in which he was asked about the age of the Earth:

GQ: How old do you think the Earth is?
Marco Rubio: I'm not a scientist, man. I can tell you what recorded history says, I can tell you what the Bible says, but I think that's a dispute amongst theologians and I think it has nothing to do with the gross domestic product or economic growth of the United States. I think the age of the universe has zero to do with how our economy is going to grow. I'm not a scientist. I don't think I'm qualified to answer a question like that. At the end of the day, I think there are multiple theories out there on how the universe was created and I think this is a country where people should have the opportunity to teach them all. I think parents should be able to teach their kids what their faith says, what science says. Whether the Earth was created in 7 days, or 7 actual eras, I'm not sure we'll ever be able to answer that. It's one of the great mysteries.

Since it is one of the most essential functions of the news media to catch Republican politicians saying dumb things and then discuss the sheer dumbness of what was said for as long as possible, we'll be hearing about this for a while. I'm not clear from Rubio's answer whether he thinks is something of a Young Earth creationist, and he's trying to sound less scary about it, or whether he just wants to avoid offending the sensibilities of those who are Young Earth creationists by not flatly disagreeing with them. Either way it's a bit dispiriting.

Rubio makes the argument that the age of the universe doesn't actually have anything to do with the sort of everyday concerns that a Senator deals with. Over at Forbes, Alex Knapp points out that the age of the universe actually does have huge implications for the kind of science we deal with in our everyday lives.

The emphasis in Rubio’s statement is mine. I say that because the age of the universe has a lot to do with how our economy is going to grow. That’s because large parts of the economy absolutely depend on scientists being right about either the age of the Universe or the laws of the Universe that allow scientists to determine its age. For example, astronomers recently discovered a galaxy that is over 13 billion light years away from Earth. That is, at its distance, it took the light from the Galaxy over 13 billion years to reach us.

Now, Marco Rubio’s Republican colleague Representative Paul Broun, who sits on the House Committee on Science and Technology, recently stated that it was his belief that the Universe is only 9,000 years old. Well, if Broun is right and physicists are wrong, then we have a real problem. Virtually all modern technology relies on optics in some way, shape or form. And in the science of optics, the fact that the speed of light is constant in a vacuum is taken for granted. But the speed of light must not be constant if the universe is only 9,000 years old. It must be capable of being much, much faster. That means that the fundamental physics underlying the Internet, DVDs, laser surgery, and many many more critical parts of the economy are based on bad science. The consequences of that could be drastic, given our dependence on optics for our economic growth.

Here’s an even more disturbing thought – scientists currently believe that the Earth is about 4.54 billion years old because radioactive substances decay at generally stable rates. Accordingly, by observing how much of a radioactive substance has decayed, scientists are able to determine how old that substance is. However, if the Earth is only 9,000 years old, then radioactive decay rates are unstable and subject to rapid acceleration under completely unknown circumstances. This poses an enormous danger to the country’s nuclear power plants, which could undergo an unanticipated meltdown at any time due to currently unpredictable circumstances. Likewise, accelerated decay could lead to the detonation of our nuclear weapons, and cause injuries and death to people undergoing radioactive treatments in hospitals. Any of these circumstances would obviously have a large economic impact.

Knapp does a good job of pointing out that issues like the age of the universe are not simple trivia from a scientific point of view. If someone were really serious about believing that the universe was only 9,000 years old, it would imply that a lot of the physical laws we take for granted at the moment (a lot of our paradigms) are wrong. I think it's important that people have an understanding of how seemingly separate areas of scientific knowledge are in fact intimately tied together, so this is a very useful reminder.

That said, I think this misses something about the way in which most people who say that they think the Earth is only a few thousand years old actually use that belief. I've read explanations by Creationists that attempt to put together some story as to how we see light from objects more than 10,000 light years away, how radioactive decay could have been faster in the past, etc. in order to explain how the world looks the way it is while being less than 10,000 years old. However, these explanations invariably seem to be focused on coming up with an explanation as to how things used to be different for a while in the past -- they never attempt to make any predictions about the world behaving in strange and unexpected ways in the future. This is, of course, one of the several reasons that "creation science" can't really be considered a science, it's not predictive. Creation science is the attempt to use scientific language to explain how two seemingly incompatible things could be true: the world could look and act the way it does now (far away objects, radio isotope dating, fossils, etc.) and yet be very young. However, now and in the future, "creation science" is comfortable assuming that the world will continue to work exactly the way it does now -- not in the crazy ways it allegedly did for a couple days 9,000 years ago.

One can simply see that as being very bad science, and I think that's certainly appropriate. But as I think about Rubio's comments in particular, it strikes me that part of what's going on in many cases when people express doubts as to the age of the universe is that they're effectively walling off the question of the age of the universe and choosing to think of that in a context other than a scientific one. Sen. Rubio's expressed doubts as the the Earth's age and Rep. Broun's expressed belief that it's only 9,000 years old don't actually have any implications for science and technology applications in the present because they don't think about the age of the universe as a scientific question. I doubt very much that they expect the laws of physics to suddenly start acting differently any more than any other person does. Like anyone else making the leap from inductive knowledge to general laws, they are quite happy to act as if the speed of light and the breakdown of radioactive elements is constant. They just don't want to apply those practical beliefs to the question of the age of the universe.

In one sense, this isn't that odd. There are lots of areas of life where we don't attempt to apply science as a way of answering questions because science is incompetent to answer them. Examples of such questions would include: What is the meaning of life? Does my wife love me? Is Brahms better than Shostakovich? Should I become an academic or go into business?

What is odd is that those who believe in or hold open the possibility of a young earth are choosing to take a topic which science would appear to be well suited to "How old is the Earth?" and choosing to hold that out as an area where they do not apply science.

UPDATE: Of course, it's not just the Right that has its science problems. As a friend quipped on Facebook: "Rubio says he doesn't know the earth's age. Obama says he doesn't know when life begins." One of those is more likely than the other to result in making bad decisions.