With Freeman Dyson:

My optimism about the long-term survival of life comes mainly from imagining what will happen when life escapes from this planet and becomes adapted to living in vacuum. There is then no real barrier to stop life from spreading through the universe. Hopping from one world to another will be about as easy as hopping from one island in the Pacific to another. And then life will diversify to fill the infinite variety of ecological niches in the universe, as it has done already on this planet.

If you want an intellectual principle to give this picture a philosophical name, you can call it "The Principle of Maximum Diversity." The principle of maximum diversity says that life evolves to make the universe as interesting as possible. A rain-forest contains a huge number of diverse species because specialization is cost-effective, just as Adam Smith observed in human societies. But I am impressed more by the visible examples of diversity in rain-forests and coral-reefs and human cultures than by any abstract philosophical principles.

I agree. This is one of my fundamental religious beliefs.

The Principle of Maximum Diversity.

Professor Harold Bloom of Yale University is my favorite literary critic. This excerpt repeats one of Bloom's off-hand observations that The Blessing which is handed down in Jewish Scripture (if you are Jewish there is nothing "old" about the Old Testament) is actually nothing more (or less) than the promise of life:

We read Shakespeare, Dante, Chaucer, Cervantes, Dickens, Proust, and all their peers because they more than enlarge life. Pragmatically, they have become the Blessing, in its true Yahwistic sense of "more life into a time without boundaries.

To enlarge Life, both in quantity and quality, to extend Life into time and space without boundaries simply is what we were commanded to do and what we were promised in The Book of Genesis.

Terraform Mars? Fill the solar system with a diverse multitude of life? Hey, its just the most recent chapter in a story that saw Avrum leave the city of Ur to found a new people in the wilds of Canaan.

And thus, when all is said and done, space exploration is about making babies, out there.

Rand, we may share at least some fundamental religious beliefs even if we disagree strongly on other points.

Cheers!

But why hop from island to island (ie, deep gravity wells) when the ocean is where the excitement is. :-)

Same here Rand & others; life, freedom, and diversity go hand in hand. Looking at the world I fail to see how anything else could be the case (and since I believe in God I believe it's intentional).

Do steamship (however the steam may be generated) captains worry as much about the wind as pure sail captains?

If you have the ability to cross interstellar space in anything approaching reasonable times (no, I don't mean FTL, though that would be welcome. Just relativistically meaningful fractions of c), then another few tens of thousands feet per second to get on and off anything sufficently un-massive to be a planet is nothing (yes, gas giants have other issues, like pressure and no surfaces at all, but that's not my point).

Concerns about gravity wells* are for wimp civilizations that haven't developed serious propulsion yet...

(* Well, anything less than those of close-range white dwarfs / neutron stars / stellar black holes)

Of course, if the life-forms that manage to adapt to vacuum and spread far and wide through space are hostile towards humans, then maybe the word optimism is inappropriate (at least from our standpoint).

Frank Glover I think it depends on personal preferences and I'm not going to keep anyone from settling other planetary bodies, nor do I think Karl Hallowell will want to stop you ^_^

I would much more prefer to live (as in "spend most my time") on an 1g space island (preferably of my own design as I'm not completely satisfied with several aspects or missing details of the O'Neil ones) than on the surface of Luna or Mars. A 1g Venusian blimp habitat might be interesting as well but the main reason I like the idea of free-space habitats is not only the 1g environment (not that they have to be 1g on the inner surface), and that almost nonexisting escape velocity, and the plentiful energy, but that such space habitats might themselves travel between destinations (destinations I will be as suited to visiting as if I still lived on Earth).

Such inter-orbit travel might not make much sense for the enormous habitats seen as the goal by O'Neil but I'm not aiming for those.

Well, the obvious flaw in his argument is that life has already had bazillions of years to colonize interstellar space, and it hasn't. To paraphrase Fermi, if life in a vacuum were at all possible, where is it? It's not like the Universe has been waiting around to display the full range of its possibilities until H. sapiens evolved to appreciate them.

But why hop from island to island (ie, deep gravity wells) when the ocean is where the excitement is. :-)

First, I agree.

Second, we need practice before we can live in deep space. Mars is the 2nd safest place in the solar system to raise a family (after Earth) with water and carbon dioxide (3 of the 4 needed for CHON chains) and 3/8th gravity.

Children of children born on Mars will be well suited to move on to free floating colonies.

As far as L-5 style colonies, why stay in one place? Build a whole bunch of L-5 colonies and send them on free return trajectories around various other planets.

Then, the Dyson sphere to capture ALL of Sol's energy. ;-)

Then, the Dyson sphere...

Photons, phooey. Gravity is where it's at. Learn to manipulate spacetime directly and the universe is your oyster. FTL motorcycles, widgets to speed up, slow down, or stop the clock, near infinite energy weapons. Everything a guy needs to impress the babes.

Step by step, Carl

But yes, once we learn to manipulate gravity we can perhaps create entire new universes. I was recently reading about a theory that our cosmos has the cosmological constants it does because certain key bits of information were conveyed via a prior collpasing black hole into our Big Bang.

A multi-verse theory with cosmological evolution.

How cool is that?

The universe is probably already big enough as it is (the size at which the expansion of the universe prevents light from traversing it end-to-end, not sure if it's a fact yet) so I don't think we need more space, more matter perhaps (unless it turns out that matter is slowly being created from underlying quantum fluctuations occuring "undiluted" throughout the universe*) but not more space ^_^

I think interstellar lifeforms will have a very hard time and thus are less likely to exist than for example "free-floating" lifeforms orbiting and feeding off a sun (severely limited by how far away they can travel and still get enough nourishment to survive). So I'm not going to worry about the Invasion of the Monster Giant Space Jellyfish ^_^

* the universal quantum fluctuation being udiluted is science fact as far as I know, but it might just be "mathematical" and I'm not prepared to bet on it.

the universal quantum fluctuation being udiluted is science fact as far as I know, but it might just be "mathematical" and I'm not prepared to bet on it.

I can help you out here, since once thing I do know pretty well is quantum mechanics. There's nothing purely mathematical about fluctuations in the vacuum. They're well understood. The problem is that they don't conserve energy. Fortunately energy only needs to be conserved when you make measurements. Between measurements -- when, for all we know, the universe ceases to exist, or all the stars of spectral class O and above turn into pumpkins -- energy needn't be conserved, and particle-antiparticle pairs can jump out of nothing at all and zoom about.

However, they have to recombine and vanish before you measure the energy again. Sort of like the kids may jump wildly on the bed when you close the door, but they're back under the covers, eyes closed, innocently sleeping when you open the door again to see what all the noise is about.

That doesn't mean quantum fluctuations have zero effect by any means, but it does mean they can't stick around indefinitely, contribute to an increase in "permanent" matter.

There is one exception I know about, which is Hawking radiation. In this case, when pairs are created very near a black hole, one of them can drift across the event horizon. Since it can never recombine with its partner, the partner becomes part of the "permanent" matter of the Universe. Of course, since energy must be conserved, the black hole itself has to lose the equivalent mass. Eventually it can entirely evaporate through this mechanism.

I don't know of any mechanism to support spontaneous creation of "permanent" matter -- those better informed about HEP might -- but there's certainly enough energy down near the Planck length to do it. Problem is, we have no theory for down there where gravity* dominates.

* Gravity again! Vide supra.

That's good to know Carl, I might annoy you with a terribly uneducated question from time to time hehe ^_^ I feel like I should apologize in advance. And I guess I should add I was afraid so regarding quantum fluctuations.

I suffer from this strange notion of an expanding universe creating (or more like "growing" to my mind) matter as a consequence of some threshold level of emptyness and/or weakness of any fields. It makes for a completely unscientific "too cool not to be the case" idea I have a hard time shaking off ^_^ The problem is of course that I doubt there would be any way of telling if it even happens (which I gladly admit is unlikely) except for hanging around for an extreme amount of time (like perhaps a few billion years) and see if one notices any unexplained differences in the amount of matter.

The universe is probably already big enough as it is (the size at which the expansion of the universe prevents light from traversing it end-to-end,

If, as the evidence seems to indicate, the cosmological constant is a constant and is substantially nonzero, then the galaxies we can see at sufficiently high red shifts are already unreachable by any signal limited to the speed of light.

As the universe expands eventually all galaxies not bound to ours (the Local Group) will flee over this horizon and be forever lost to ours.

Believe in the Big Rip, do you, Paul?

Carl,

You make an excellent point when you paraphrase Fermi. I am an optimist by nature and very much want to believe Dyson. But intellectually I can never get over the hurdle you refer to. In fact, I'm posting this in the hope that someone will come up with an argument I can cling to.

Carl:

"Well, the obvious flaw in his argument is that life has already had bazillions of years to colonize interstellar space, and it hasn't."

13.7 billion years isn't infinity. Further as the article points out HAR1 did not evolve linearly in time. If you had been watching the experiment on earth 7 million years ago, would you say something like:

"Well, the obvious flaw in his argument is that life has already had bazillions of years to produce intelligent life, and it hasn't."

What was that theory again that describes evolution in fits and starts.. Punctuated Equilibrium?

Bill White:

Space may be for making babies, but I'd hold off for now. ;-) I know you bring this (let's make babies theme) up often...Even Dyson quite approves of curbing population growth on this, the currently only habitable planet. It's a bit hard to appreciate the diversity of the earth if we overbreed. Replacement or less should be the goal for now..until we figure out how to live in a vacuum etc.

The "Big Rip" (where the universe eventually tears itself apart even on subatomic scales) is even more extreme (effectively the cosmological "constant" increases with time). Instead, you have basically a minute constant expansion of spacetime so near space should continue to look normal, but things very far away (billions of light years) look further away that you expect. Also space is bigger than in a zero cosmological constant universe. If you look at the volume of a four-dimensional sphere, in addition to increasing as the fourth power of radius, it has an exponential factor proportional to the cosmological constant.

Paul Dietz:
Thanks for the clarification, interesting stuff.

Toast'n'Tea:
The idea of a Malthusian catastrophe that saw a revival of popularity in the late sixties is somewhat of a tautology and thus somewhat meaningless since it talks about unrestricted growth when growth obviously always meets at least inherent and escalating restrictions. With that in mind it should surprise no-one that we presently have a falling (yet not negative) rate of population growth in the world. As India and China become more successful this will likely drop further.

If we add to that a future in which those of us that are free strive to make more areas of the world democratic (which without fail seems to lead to a rise in wealth, freedoms, and education -particularly for females) then we're likely to see growing underpopulation rather than overpopulation.

I predict a "Global Underpopulation" scare as a rallying cry for the masses some time in the not-too-distant future (decades).

Go make babies, raise them to the best of your ability, and be happy ^_^

Here's a wild-assed thought experiment...

Why not instigate panspermia ourselves?

Find some ponds, maybe a dozen or so, freeze them solid with a truck or so of liquid nitrogen, scoop them up, and launch them into space at solar escape velocity. Maybe set them up with small explosives to break apart at the Kuiper belt range, so that various sized chunks go off in nearly identical galactic orbits. Sort of shotgunning random DNA out into the universe. Sure, we won't live to see the results, if any, but maybe in a couple hundred million years whoever comes after us might find a slightly less lonely galaxy...