Thanks for the compliment, but I thank you even more for the criticism.
When it comes to generational ships, there’s really no set-in-stone requirement that such will be necessary for interstellar travel. The problems inherent in such are legion, but nothing that we can’t overcome. One might think it’s a stretch to compare them to our modern supercarriers (I served on such for a total of eight years out of a twenty-year career in the Navy), but…well, we went from the age of wooden ships and iron men to the age of nuclear carriers and internet trolls in less than two hundred years. That being said, the biggest problem with generational ships has less to do with hardware engineering and more to do with (1) the human condition, the psychological and social hazards of confinement in a tin can (however big that tin can may be), and (2) the physiological effects of spaceflight over the span of lifetimes (even with gravity generated by a large ship’s spin). The second of these is actually the easier to overcome, especially with the advent of CRISPR technology. But (Asimov’s theory of psychohistory not being applicable on relatively small populations), there’s no way to predict or allow for what people will do. In, say, a thousand-year voyage, even assuming the spacecraft lasts that long, can there really be any doubt that there would sooner or later be deadly conflict between groups to the extent that the entire habitat would be endangered? That’s why, in my certainly-unqualified opinion, the only real hope for a successful sub-lightspeed transit over hundreds or thousands of years is if we develop long-term hibernation reliable enough to allow awakening with little- or no loss of physical or intellectual capability…and I’m pessimistic at best that such is even possible. I really hope I’m wrong.
Fortunately, history over the past three centuries shows that mankind has developed an annoying habit of eventually doing things undreamt-of a few generations earlier. My personal hope is that we’ll find a way to make an Albucierre drive practical, since the energy required (in the estimates of theoreticians) has dropped precipitously over the years. Yes, the current estimate is still far beyond our current capability…but hope springs eternal.
I strongly agree with you when it comes to Von Neumann probes. I’ve been thinking for a long time about writing such a novel. Feynman first pointed the way to nanoscale engineering. I’ve long thought that such may be the only practical way to build a space elevator (by cannibalizing a large carbonaceous asteroid), to terraform distant (sterile) planets, and perhaps even to carry “seedlings” of our DNA to distant worlds.
Interestingly enough, just this morning I was looking at the Bobiverse books on Audible, trying to decide whether to get the first one or to get Will Durant’s “Life of Greece”, the second volume of his masterwork “The Story of Civilization”. I’ll go with your recommendation.