Population reduction isn't necessary for wilderness (was Space habitats)

--- In spacesettlers, "hitssquad" wrote:

> Energy from space (to Earth) isn't realistic, given the
> presence of cheaper alternatives.

Ah, gee. I guess we should just give up then.
The alternatives are cheaper RIGHT NOW because
a) it's so expensive to launch anything into space,

b) we don't have the infrastructure in place to make stuff
IN SPACE from stuff already IN SPACE, and

c) the alternatives are are not priced according to their
full cost (it doesn't cost you more to buy a gallon of
gasoline it cost a Kg of pollutants to refine than to buy
a gallon of gasoline it cost a g of pollutants to refine),
and finally,

d) the alternatives are subsidized while space solar power
is not.

> A population of less than a billion is realistic, but not
> necessary. Most of the planet could be set aside as a
> nature preserve even with an Earth population of a trillion.

With unlimited clean, cheap energy and aggressive recycling,
and people living in dense arcologies, maybe.

> Also realistic would be 100 trillion on Earth, and another
> 100 trillion on Venus.

I'm not going to say it's utterly impossible, but I will say
that calling this "realistic" while saying that power from
space solar is not, is pretty silly.

> A compounding APR of 3.4% would do it (implying 28x growth
> per century).

This I want to look into a bit. How does this compare with
the last century, or the one before that? After all, a whole
lot of things become realistic with growth like that.

> Venus's greater natural-abundance of nitrogen.

I doubt not that this will eventually come in handy.