How is prime factorization ‘unsolvable’ on a classic computer? It seems like something any programmer could pound out a simple program to do pretty easily.

It would be slow as heck for really big values, due to recursion involved, but it would eventually give a solution.

Is there some kind of math definition of ‘solved’ that I’m unfamiliar with?

Great Filter.

To go interstellar, you need very powerful energy generation and storage. The kind of tech that can do so can be easily repurposed into making really big bombs. Therefore, any potentially spacefaring civilization definitionally has access to at least nuclear scale weapons.

I believe the great filter is ‘can we use this technology to get off this rock before we use it to blow everyone up.’ Which, considering that our Cold War came dangerously close on several occasions, and we haven’t had them for that long, I don’t hold out much hope for ourselves or any other civilization.

I should probably be dead by now, but as my grandmother used to tell me: