The Lingering Appeal of Geocentricism
One expects science-themed documentaries to illuminate and educate—think of the recent hit show Cosmos: A Spacetime Odyssey or the climate change broadside An Inconvenient Truth. But in recent years, a small handful of science documentaries have been produced not as instructive tools for understanding our world, but as anti-science propaganda. Films like Expelled: No Intelligence Allowed and Cool It ignore mainstream and accepted scientific research in pursuit of their own conservative agendas. The Principle, which challenges the Copernican Principle in favor of the notion that the Earth is the center of the universe, is the latest in a wave of right-wing docs that have established scientists scratching their heads—even those who appear in it.
Earlier this year, one of the featured talking heads in The Principle, prominent cosmologist and theoretical physicist Lawrence M. Krauss, director of the Arizona State University Origins Project, and author of A Universe from Nothing, wrote an article in Slate entitled, “I Have No Idea How I Ended Up in That Stupid Geocentrism Documentary," in which he explains how he may have been misled and quoted out of context. For Sloan Science and Film, Krauss spoke about some of the fallacies and fascinations of the geocentric model, and the hard scientific evidence that helps explain the spontaneous birth of the universe some 13.8 billion years ago.
Sloan Science and Film: How old is this geocentric model?
Lawrence M. Krauss: It goes back to the early Middle Ages. Maybe earlier than that. The Greeks probably knew better. The point is that it’s in the dustbin of history. So there’s no sense worrying about it or resurrecting it. As a scientist, the great thing about incorrect models is that you can throw them out and forget about them. At least that’s what I thought. But there are still people who believe the earth is flat, so I guess nothing should surprise me.
SSF: Can you lay out the Copernican model which helped pave the way for our current understanding of the universe?
LK: Copernicus suggested the planets were in spherical orbits around the sun. That agreed far less with the data than the other models, but it wasn’t until [Johannes] Kepler that the actual real model of the solar system, with planets in ellipsis orbiting the sun, got better than the old heliocentric model. But now the point is that it’s not just a matter of choosing between two models, and which fits the data better. We can do much more than that: We can actually check with our satellites. Originally, it was just two models, and one fit the data better and more importantly, allowed you to make other predictions. For example, when Galileo saw the moons orbiting Jupiter, it really convinced people that not everything orbits the earth.
SSF: There’s something in The Principle about recently discovered cosmic measurements that showed forces pulling toward the earth.
LK: When the cosmic microwave background measurements—the afterglow of the Big Bang—came out we could see radiation coming at us from all directions from the time the universe was about 300,000 years old. What was surprising in some of the earlier versions of the data, or some people’s analyses of those versions, were some anomalies in the data that mysteriously lined up with the earth’s position in the solar system. But scientists just made fun of it; if you have a big data set, there are always things that are peculiar. When the documentary filmmakers talked to me, I said something to the effect that it was “intriguing.” But anything that they may have harped on in the movie is not relevant.
SSF: What do you think is the attraction of the geocentric model that keeps it from going away?
LK: It has gone away. I think the attraction for some is the following: It’s the same people who think the earth is 6,000 years old. For them, the reality of the universe is a threat to their religious faith. Therefore, they disregard all the evidence from the last 500 years and cling to this ridiculous belief that the earth is 6,000 years old or that the earth is somehow the center of the universe, because they want to be special. They want God to have created the universe for us. And I’m pretty sure that this is the motivation for this film, holding on to some poorly adopted idea that makes them feel warm and cozy.
SSF: We should probably note that being cosmologist doesn’t prevent you from having faith in God, right?
LK: Being a scientist doesn’t require you not to believe in God. That’s not to say science provides evidence for God; it provides none whatsoever. The point is that The Big Bang happened and the universe is 13.8 billion years old, whether or not you believe it. So if your belief in God requires you to disregard the evidence, you should reexamine your belief in God. And the first person who said that was Moses Maimonides, a Jewish scholar in the 11th century.
SSF: Where do you stand on the evidence of what caused the Big Bang?
LK: I wrote a whole book about it. As far as we can tell, the universe spontaneously came into existence from nothing. And the laws of quantum mechanics allow that. There’s no cause, per se, except for the laws of physics. But more importantly, since space and time in our universe came into our existence, it’s quite possible there was no before. And if there’s no before, we can’t talk about causes, can we?
SSF: Can you talk about the hard science that helps explain that?
LK: Quantum mechanics says things are fluctuating all the time, and in space, particles, virtual particles and anti-particles are popping in and out of existence all the time. If a particle/anti-particle pair has energy, it would violate the conservation of energy to exist for a long time. But quantum mechanics says over time, you can violate that law, which is why virtual particles can exist and not exist. But if a particle/anti-particle pair were created with zero energy, it could persist forever. Once you allow gravity into the mix, which has negative potential energy, you can imagine creating a particle/anti-particle pair with zero total energy, and then it could exist. So the first answer to why is there something rather than nothing is that “nothing” is unstable—empty space is unstable. But if gravity is a quantum mechanical theory, and we now think it is, then space and time themselves become dynamical and it’s perfectly possible to spontaneously create universes. Ultimately, if you ask what are the characteristics of a universe that would be created in that way, they would be precisely the characteristics of the universe we live in. Does that prove that was the case? No. But that’s largely what that particular book was about.
SSF: Now that you’ve written a book about one of the great mysteries of the universe, what is next in your research? What’s exciting to you right now?
LK: I just wrote an article for Scientific American about the potential discovery of gravitational waves, which may allow us to turn metaphysics into physics. It would, in principle, give us a signal a billionth of a billionth of a billionth of a billionth of a second after the Big Bang, which would increase our handle on the universe by 49 orders of magnitude. So it’s incredibly exciting. That, and I spend a lot of time trying to think about the nature of dark matter, and ways we can detect it. And with the discovery of the Higgs in particle physics, and what that may tell us about the early universe and how we use that to understand dark energy. Those are some of the things I’m thinking about now.