I am actively engaged in a religious debate forum where many Christians claim that astronomers are almost all Christians. They say the universe is so complex and yet orderly. If there isn't a God, it would be chaotic, they claim. I am undecided, but I would really like your opinion on the matter.
First of all, there are plenty of people who believe in God who aren't Christians - either members of other organized religions or just people who believe in a deity or greater power but don't subscribe to any of the tenets of a particular religion. So it seems like you really have two questions: (1) what percentage of astronomers are Christians? and (2) what percentage of astronomers believe in God?
I know there have been a lot of surveys done over the years about these questions (at least polls of scientists in the United States - I'm not sure how much it's been done in other countries). As with all surveys, their methodologies are open to question so it's not always easy to say how reliable the results are. I am aware of at least one survey published in the scientific journal Nature in the 1990's which showed that around 60% of American scientists (astronomers and otherwise) either do not believe in or doubt the existence of God. This definitely represents a greater rate of disbelief and doubt than the U.S. population as a whole. Personally, I am often skeptical of the detailed results of these surveys, simply because I think a lot of people's answers to the questions depend on how the questions are asked. It's possible to believe in God but yet still have doubts, and sometimes surveys don't seem to do a very good job making this distinction.
As for me, I do think that modern science leaves plenty of room for the existence of God and that there are plenty of places where people who do believe in God can fit their beliefs in the scientific framework without creating any contradictions. (This is not, however, the same as saying science proves or requires the existence of God, as I will explain below.) A couple examples in particular:
(1) The Big Bang. We have extremely strong evidence that the universe as we know it had a beginning, that everything which we can think of, matter and space alike, started off compressed together and has been expanding ever since. The fact that the universe is developing and not just standing still certainly makes the questions of how it started, where it's going, etc. very relevant, and a lot of people might find a place for God in trying to answer those questions.
(2) Quantum mechanics. We know from quantum mechanics that at the microscopic level, our world has an inherent uncertainty. If you make measurements of microscopic particles, there is absolutely no way you can predict the results of a given measurement. The probability of getting a particular measurement (if you do the experiment many times) can be accurately calculated beforehand, but quantum mechanics tells us that there is absolutely no way to determine what the result of a given measurement will be because the microscopic particle simply DOES NOT HAVE the property you are trying to measure until you actually measure it - it is in a "superposition of states" consisting of all possible outcomes, and when you measure it, it "chooses" one of these particular outcomes to be in. This of course raises the question of how the particle does this "choosing", and I think many people might see the possibility of God intervening every time a measurement (or any event on the microscopic level of our world, for that matter) occurs. This would then be a God who was bound by certain general rules (the probabilities of particular outcomes to the measurement) but who had freedom to choose the results of any particular set of measurements and to influence the world in that way. (Note added September 2003: Strictly speaking, quantum mechanics does not require that the universe behaves indeterministically in this way, i.e. where the particle mysteriously "chooses" its properties at the moment a measurement is made. However, it is the simplest interpretation that we have to explain experimental results obtained on the microscopic level, and thanks to the amazing mathematical result known as Bell's Inequality and the experiments that followed its discovery, we know that there is only one possible alternative to the above interpretation. This alternative is in some ways more profound; it would require a universe in which the properties of an individual particle are instantaneously and continuously altered by the actions of other particles located at arbitrarily large distances away, with no obvious mechanism in place for the alteration to occur. Standard quantum mechanics, meanwhile, still requires instantaneous communication in some cases, but only at the moment the measurement is made.)
However, the bottom line of what I think is this: science has not even come close to being able to prove (or disprove) the existence of God, and perhaps never will. So whatever the real statistics for how many astronomers believe in God, I don't think there's a single competent astronomer out there who believes in God because of his or her work in astronomy. Astronomers may believe in God for other reasons, and in that case they may find aspects of astronomy which allow them to comfortably fit their conception of God, such as some of the ideas I discussed in the above paragraph. Some astronomers might even go so far as to say that astronomy contributed to their belief in God. For example, some people believe in God because of an impression they have that the world is a beautiful place with many complex, wonderful things in it. To the extent that science consists of allowing us to see more of these things (such as faraway galaxies, the structure of molecules, etc.) it might contribute to the strength of their belief. But I guess what I'm worried about is when people get into the part of science that consists of trying to explain the causes of things we see (i.e., scientific theory) and take a specific example from this part of science and say "Look! This fact proves/disproves the existence of God!" I really don't think that is legitimately possible to do with anything that science has discovered so far.
The ultimate point is that science does not deal with belief; it deals with things that you can prove. And since we can't prove or disprove the existence of God, the question of whether or not a person believes in God doesn't (or at the very least shouldn't) have anything to do with scientific reasoning.
Note added 2016: Here are some related discussions:
- Do astronomers believe in a divine creator? from our June 2014 Reddit AMA. (Summary: "Some of us do, and some of us don't.")
- Do you believe in the Big Bang theory, or Creation? from Dr. Sten Odenwald's Astronomy Cafe. (Summary: "You are asking me to compare two things that have nothing to do with each other.")
- What should I tell my daughter about the creation of the Universe? from NASA Goddard Space Flight Center's "Ask an Astrophysicist". (Summary: "Scientists are concerned with the 'whats' and 'hows' of the Universe, rather than whether or not there is a 'why'.")
This page was last updated on March 31, 2016.