Facts do not cease to exist because they are ignored. -Aldous Huxley
People who don’t like their beliefs being laughed at shouldn’t have such funny beliefs. -Anonymous
Over at The World’s Fair, the question of belief in science arose with the provocative question, “Do you believe in the Big Bang?” I thought about it for a few seconds. What popped into my head?
The thought that, 13.7 billion years ago, all of the matter and energy within our observable Universe was concentrated into a space no bigger than the size of a single proton. That the incredibly high densities and temperatures in this region caused an expansion at nearly light-speed. As the Universe expanded and cooled, protons and neutrons formed,
nuclear fusion happened for the first time, producing nearly all of the deuterium, helium, lithium and beryllium in the Universe,
and eventually neutral atoms formed, leaving behind the relic radiation from the big bang, which is still cooling today, and which has been discovered as the Cosmic Microwave Background.
“Yes,” I thought to myself, “I do, in fact, believe in the Big Bang.” It is superior to all of the proposed alternatives, it is consistent with all of our observations, and it makes predictions that have allowed us to discover new things about the Universe. What more could one need to be convinced of its validity, and hence, to believe in it?
What’s more, I reasoned, is that if an observation came up that was in conflict with the Big Bang, I would either need to explain the observation or revise my belief in the Big Bang. And if another, superior scientific theory came along, I might be compelled to believe in that in lieu of the Big Bang.
But after showing his class Lauren Gunderson’s play, Background, about Ralph Alpher (a student of Gamow’s) and the prediction and discovery of the cosmic microwave background, Vince asked his students to define “nucleosynthesis.” Let’s listen to Vince’s account:
The answer is that Big Bang nucleosynthesis is the formation of several different elements (including deuterium, helium, beryllium, and lithium) from protons and neutrons during the first 2-5 minutes after the Big Bang. What was interesting was that one student gave exactly that answer, then added “if you believe in the Big Bang.”
Now, Vince (and many of his commenters) have a problem with this. Specifically, with the “belief” aspect. The discussion spirals down into a “science vs. religion” debate after that.
Why? Why can one not believe in the Big Bang as opposed to the major rival theory of the day, the Steady State Model? (In which, incidentally, “nucleosynthesis” has a very different definition.) Why cannot one “believe” in global warming, as a preponderance of the evidence supports it, or “believe” in evolution or general relativity or any other scientific theory, as opposed to any other alternatives? Why cannot one make the best decision one can with the information available and stand behind it with conviction, whether it’s to believe or disbelieve string theory, supersymmetry, quantum gravity, or any other theory? What’s the worst that happens; that new evidence comes in and proves you wrong, forcing you to either change your beliefs or continue being knowingly wrong?
If I look up believe, I find:
to have confidence in the truth, the existence, or the reliability of something, although without absolute proof that one is right in doing so.
In science, we never have absolute proof. We are always subject to observations and experiments, and to new data forcing us to revise our theories, opinions, and yes, our beliefs. Why do we not reclaim this word, and use it to mean exactly what it means? Or, to be blunt, what, exactly, is the problem with having an informed belief in a scientific theory?