> “The abc conjecture is a very elementary statement about multiplication and addition,” said Minhyong Kim of the University of Oxford. It’s the kind of statement, he said, where “you feel like you’re revealing some kind of very fundamental structure about number systems in general that you hadn’t seen before.” I can kind of see that, but there's something in it that gives me the feeling of arbitrariness. It's lookin…
Another way to think about it is to consider what needs to happen for rad(abc) to be much less than c. This can only happen if the "dropping" you mention drops a whole lot of factors. In other words, it can only happen if a, b, and c all contain mostly large powers of primes. The prime factorization of a number is essentially "random". That makes numbers that are large powers of primes rare; it's like rolling a die a…
> And that seems to be roughly what the abc conjecture says: it is not likely that all of a, b, and c are rare.
It almost sounds like a tautology. Is your view that it is somewhat vacuous after all? Or maybe the interest comes from the fact that while it seems obviously true, we need a proof in order to use it as a theorem for other things where it would be a useful tool...