Reply To: Toshiba's "Micro Nuclear Reactor" – it's not fusion, but it's here now

[Lerner]

I think it is relevant, and it is not selfish if what we are talking about is slowing aging. It’s not selfish to want to stick around longer—even a couple of centuries longer– assuming you are doing the world some good. We would all very much miss you, Rez, if you weren’t around! People having much longer lives would actually make advances like fusion easier in some ways—I wish I could ask some questions of Bostick and Nardi, pioneers of the DPF, who are now dead.
Clearly aging can be radically changed—look at the differences in life spans among dog breeds, which are all the same species.
But to have longer life spans, you need a rapidly growing population. Otherwise, you have too many old people relative to young ones. Even if there were very slow aging, people do get stuck in their ways for social, not biological, reasons. If there is rapid population growth—say 2% per year, the 200- year old people are a very small fraction of the population and most people are young. That’s what you get if the average couple has two kids by age 35. The median age will also be 35.
A rapidly growing population with a decent standard of living requires aneutronic fusion. Also eventually space travel to someplace nice, but we won’t run out of actual living space on Earth for a long time.