I've been following Alicorn's sequence on luminousness, that is, on getting to know ourselves better. I had lowered my estimate of my own rationality when she mentioned that we tend to think too highly of ourselves, but now I can bump my estimate back up. There is at least one belief which my tribe elevates to the rank of scientific fact, yet which I think is probably wrong: I do not believe in the Big Bang.

Of course, I don't believe the universe was created a few thousand years ago either. I don't have any plausible alternative hypothesis, I just think that the arguments I have read in the many popular science physics book I have read are inconclusive.

First, these books usually justify the Big Bang theory as follows. Right now, it is an observable fact that stars are currently moving away from each other. Therefore, there was a time in the past where they were much closer. Therefore, there was a time where all the stars in the universe occupied the same point. It is this last "therefore" which I don't buy: there is no particular reason to assume that if the stars are moving away from each other right now, then they must always have done so. They could be expanding and contracting in a sort of sine wave, or something more complicated.

Second, the background radiation which is said to be leftover stray photons from the big bang. If the background radiation was a prediction of Big Bang theory, then I might have been convinced by this experimental evidence, but in fact the background radiation was discovered by accident. Only afterwards did the proponents of Big Bang theory retrofit it as a prediction of their model.

Third, the acceleration. The discovery that the expansion was accelerating was a surprise to the scientific community. In particular, it was not predicted by Big Bang theory, even though it seems like the kind of thing which an explanatory model of the expansion of the universe should have predicted right away.

Fourth, the inflation phase. This part was added later on, once it had been observed that Big Bang theory did not fit with the observed homogeneousness of the cosmos. To me, this seems like a desperate and ad hod attempt to fix a broken theory.

Now, it could be that all these changes are a progression of refinements, just like Newtonian physics was adjusted to take into account the effects of relativity, and just like the spherical Earth was adjusted to make it an elliptical Earth. But the adjustments which Big Bang theory has suffered seem like they should change the predictions completely, rather than, as in the other cases, increasing the precision of the existing theory.

I am, of course, open to being convinced otherwise. If Big Bang theory really is true, then I wish to believe it is true.