> We don't have a good idea of how to go faster than we can now without literally blowing up nukes behind our ship, and hoping we can magically ride the waves r

> We don't have a good idea of how to go faster than we can now without literally blowing up nukes behind our ship, and hoping we can magically ride the waves reliably, and even that is not exactly revolutionary in terms of speed. There are other, better, designs for nuclear rockets beside the Orion drive. Some proof of concept devices have already been built. And if we could get our hands on sufficient quantities of anti-matter there are even better designs for anti-matter rockets. It’s an engineering problem not a problem of fundamental physics.