Sunday, November 29, 2009

What Alien Colonization Would Look Like

In the previous blog entry, I explored what galactic colonization must inevitably look like to any civilization conducting it.

Note that any civilization that fails to expand its technological and industrial base to the point where galactic colonization is easy and cheap will eventually become extinct due to an asteroid collision, supervolcano eruption, glaciation or global war. This argument was first made years ago and it is well-established.

Note also that such homebody civilizations have average lifespans of at most a few million years. Given the many hundreds of millions of years in our galaxy's past such blatantly suicidal fucking idiots are of no consequence to us. I would even say, if they want to die, why should we not help them die?

But that isn't the subject of this post. Here we explore what galactic colonization looks like to any hypothetical backwards inbred hillbilly civilization unfortunate enough to be trampled underneath its expansion.

As already established in the previous article, AI makes starflight cheap and distance irrelevant. It takes just as much resources to accelerate a starship to near light speed then hibernate the AI for a 10 year flight as it does to accelerate a starship to near light speed then hibernate the AI for a 100 year flight. Or a 1000 year flight, or a 10,000 year flight. Or even a 50,000 year flight. There is no friction in space.

The only difference is the increased risk of a micrometeorite vaporizing the starship. And that can be easily surmounted by building an AI with an appropriate martyr complex and fanatical dedication to its mission. Why does that matter? Because it means that the wave of colonization will NOT be lackadaisical with sporadic branching to the nearest possible systems. Rather, the wave of colonization will be perfectly spherical.

The homeworld will be launching starships one after another, with the nearest star systems first in line, and it will never stop. Because it won't matter that the nearest 1000 systems are successfully colonized, the only thing that will matter is that there's another system out there that you can send an AI colonization ship to. And it won't matter that there is no immediate benefit. At some point down the road, perhaps only in 10,000 years, the homeworld will benefit in some way. If only due to exchange of technological information. And if it doesn't benefit, it's not like the starship was expensive anyways.

Let me make the point again. Many people (even supposedly educated people who study technology) have the deeply mistaken notion that the homeworld will send a short burt of colonization ships only to the nearest star systems. Perhaps even only to the nearest "inhabitable" planets. Then, after suitable millenia when each of those systems are developed enough, they will each send out their own wave of starships. That's not going to happen. This is ludicrous Star Trek fantasy.

What's going to happen is this. The homeworld will send a single giant wave of starships to every possible star system within line-of-sight. First to Alpha Centauri then, as soon as the first ship is accelerated to near-c, then to Barnard's star, then to Wolf 359, then Lalande 21185, and so on until the last star system in the galaxy within line of sight is targeted. Once the starships are all launched then the Homeworld will simply begin targeting the globular clusters and Andromeda. This wave of colonization will occur over centuries or at most millenia.


Now some uneducated people scoff at the idea of starships going near the speed of light. They claim that humanity has no idea how to accelerate starships to that speed and that our civilization will never develop such technology even given a million years. From fire to controlled nuclear fission in 10,000 years? Certainly. But from slow starflight to fast starflight in a million years? No never. Never ever! Apparently, technological development is something that only ever happens in the past.

As it happens, we already have a good idea of how to accelerate a starship to near-lightspeed. Isaac Kuo of Bad Astronomy and Atomic Rocket fame came up with a Starship Design Concept which can easily be accelerated to such velocities using current industrial technology. The best part is that it's cheap because it's reusable. Once the launch system is built, it can accelerate 1000 starships (one after the other) as easily as it can accelerate a single one.

For those who are interested, the idea involves an array of free electron X-ray laser beam emitters in solar orbit. The beams are focused using a giant fresnel lens. They can easily target the back of a starship's solid lead plate to a distance of several light-years. This enables the starship to be driven to anything from 0.9c to 0.99c. It also enables the starship to be decelerated using the exact same mechanism (x-ray laser beams near the homeworld) within a few light-years. Not that deceleration is the difficult part.

Furthermore, since every gram of matter carried by the starship at 0.9 c has an impact of a small 9 kiloton thermonuclear explosion, the starship can spray a fine mist of gas ahead of itself to annihilate all but large meteoroids in its way. The resulting spray of elementary particles can be swept aside with a magnetic field. To carry more gas for longer journeys, it's sufficient to make the starship longer. So long as you don't increase its cross-section, you don't make it a fatter target at all.

So yes, we actually do have a good idea how to go near the speed of light. And a civilization that's dismantling its home system to build a Dyson sphere will have centuries to perfect the design before implementing it.

What You Would See

So what would you see if some alien civilization were out there, colonizing our galaxy? Well for a millenium or so you would get radio waves. Then you would see the star associated with the radio waves becoming markedly darker. Within decades or centuries you would see the nearby stars go dark. Then you would see a hemispherical wave of darkness engulf every star at an astonishing rate. Within a bare thousand years from the first star going dark, you would see every other star from that origin point to your own sun going dark. And you would see this no matter where in the galaxy you are because the Dyson-sphere building starships would be only barely slower than the light you use to see them.

This is why everyone who yammers on about invisible or "hidden" aliens is a useless twit not worth listening to. Because you can't hide the stars going dark. If aliens were out there, it would be one fucking impressive sight. And as for the SETI notion that there is an alien civilization out there in the miniscule window between "doesn't have radio technology" and "is turning off the stars you see in the sky" ... Or perhaps SETI is interested in talking to blatantly suicidal fucking idiots? I don't know. I don't care either.

Do you see those stars in the sky at night? That's all the evidence an educated person needs that aliens really aren't out there. Unless you think the Great Void between galaxies is caused by aliens. Unfortunately, it isn't because dark stars emitting in the infrared aren't even remotely the same thing as no stars at all. Dyson spheres are quite distinctive and our astronomy hasn't found any. So are partial Dyson spheres for that matter, because the stars they partially cover would vary in brightness as regularly as pulsars.

Next up, what a galactic civilization might choose to do.


S. Datskovskiy said...

All of this is perfectly logical, but only if you assume that the hypothetical aliens travel and communicate through standard spacetime. Which they might not. (I am almost entirely convinced that you have proven that they do not. Which is not quite the same as a proof of their non-existence.)

Richard Kulisz said...

You mean, you think that the laws of physics might change in the future.

First of all, this notion is entirely ridiculous and contravenes the very concept of 'universal laws of physics'.

Second of all, any relaxation whatsoever of the speed of light makes colonization FASTER and makes Fermi's paradox WORSE.

The lower bound on the average time between galactic civilizations in our galaxy is 4.6 million years. That's using the extreme assumption that galactic civilization was utterly impossible more than 65 million years ago due to magic.

Are you comfortable saying that the average time between space-going civilizations in the UNIVERSE is 4.6 million years? That in a huge fucking universe, intelligent (by which I mean far smarter than the average human has proven to be) technological civilization only arises on average 4.6 million years *in the entire universe*?!

Fermi's paradox is bad enough using only our Milky Way, but as soon as you allow for faster than light travel, exponential growth (and thus the Paradox) stretches to encompass the entire universe. As soon as you allow for unlimited time travel, it stretches to encompass the future. And as soon as you allow travel between parallel realities, it stretches to encompass the entire multiverse.

And are you really, really comfortable saying that we are the ONLY technological civilization in the whole universe / timestream / multiverse? Or that some magic causes technological civilizations to ALL die out in the universe / timestream / multiverse?

There is no escaping Fermi's paradox with FTL or other crap. It's not an escape because you would have to escape from exponential growth and there is no escape from that. So FTL just makes it worse. This is why Fermi's paradox is actually a PROOF that faster than light travel CAN NEVER BE FEASIBLE. Maybe one day it will be possible *in principle* but it can never, ever be feasible (ie, economical) even for a galactic or super-galactic civilization. EVER.

That's why I hate wide-eyed FTL advocates, especially the educated engineering types, as much as alien conspiracy theorists. Because they peddle the worst possible nonsense. How can they believe in something that reduces the chance of their existing *right now* to absolute zero? Don't they even believe in their own existence?!

Do you really want to be saying that the laws of physics in future might be understood in a way that prohibit your having ever existed?

Richard Kulisz said...

My calculation of MTBF is wrong for an exponential distribution which this problem is. It's off by 13%. There's a 63% chance a galactic civilization would arise every 4.6 million years, not a 50% chance.

S. Datskovskiy said...

> FTL just makes it worse

Given everyone sharing a physical space (as we understand it), I agree. But can we entirely rule out civilizations escaping into "parallel universes" or something equivalently inaccessible and unobservable with current tech? (Disclaimer: I am not a physicist.)

S. Datskovskiy said...

> And as soon as you allow travel between parallel realities, it stretches to encompass the entire multiverse.

I should always add that there is always another room available at the "Hilbert Hotel." We might be living in a genuinely infinite multiverse.

Richard Kulisz said...

We can't rule out a Hilbert hotel in the sense that new space gets created. So travel to the past or to alternate realities would *cause* those realities to come into existence. Or even restricted (ie, consistent) time travel back to the time travel device being turned on.

As an aside, I used to disbelieve the "something stops you from destructively changing the past" line of bullshit for its arbitrariness until it was pointed out to me that symmetry breaking was involved and that in a many-worlds universe ALL things that can prevent you from destructively changing the past HAPPEN. Just in different worlds. IOW, sending a billiard ball down a portal to knock itself off course is impossible so as soon as the portal opens and the ball is launched, it spontaneously degenerates into a billiard ball coming from the future to knock the current one off-course in just such a way that it will go back into the past and knock itself off-course. So yeah, time travel is actually possible within the same timeline. It can change the past, just not in an anti-causal way. One wonders whether the will to fake the past (the conscious decision to go back in time even if there's no "need") is sufficient to preserve causality while you massively alter the past.

For that matter, the multiverse could just be growing with a much faster exponential than any and all intelligent species within it. WHich means that naive "dimension crossing" isn't ruled out by Fermi's paradox. Just by common sense.

And last but not least, the physical universe *IS* infinite. There is no evidence whatsoever for a Big Bang. The dirty little secret of cosmology is that the Big Bang was insufficient to explain the evidence and so they came up with Inflation theory with a hot umm oozing afterwards. And the funny thing about that is that Andrei Linde showed that Eternal Inflation is by far (*infinitely far*) more likely than one-time limited inflation.

So all the physical evidence for a Big Bang had to be reinterpreted as being for hot inflation. And cosmologists being worthless moronic idiots as 90% of the human population is, kinda "forgot" to either 1) evaluate Linde's idea critically (probability of eternal inflation given ANY inflation very high, probability of our universe coming from eternal as opposed to rather one-shot inflation being infinitesimally close to 1), or they just kinda forgot that eternal inflation means there never was a big bang.

This is NOT the only case where educated top-notch senior physicists act like grossly retarded infants. The whole of quantum mechanics for the last century still takes the cake. It is however the most recent case of physicists deserving lobotomies.

Do I think there's any method of travel that can punch through the walls of a real-space universe to go in the exponentially expanding inflaton region and then into a nearby universe? No, the notion is too bizarre. And that's another reason I don't believe in FTL. Because it opens up absurd consequences like pieces of real-space (a starship) possibly going faster than an already maximally expanding bubble of real space in the inflaton. Just Just like naive (non-creationary) travel between "dimensions" causes ridiculous propabilities of probabilities ad infinitum. I try to avoid infinite regress, it's bad for business.

And I try to keep my physics away from my need to avoid mortality. I'm not willing to imagine reality in any way other than it actually is. I hate self-delusion.

On the other hand, if our universe is just a brane in a higher dimensional space then maybe there's a way to escape into the bulk. Especially with outside assistance, something we certainly will never ever get so long as 90% of humans are cretins and retards.

Richard Kulisz said...

Of course, if the only thing that matters about time travel is preserving each temporal incursion then the time-stream quickly becomes everywhere dense with temporal incursions. To the point of almost seeming non-deterministic. That's not exactly elegant, is it?

Either way the Fermi question becomes, how likely is it that we are the first civilization in our light-cone to develop time travel. Semi-probable if time travel is restricted, improbable it's open. So temporal colonization has the same Fermi implications as spacial colonization. Reconcilable if there's a limit, irreconcilable if it's unlimited.

After a lot of thought, I can't come up with any serious objections to restricted time travel. Even if it's taken in combination with FTL, the objections to it boil down to the same objections against FTL. That is, how likely is it that it took 12.7 billion years for any civilization in the whole universe to develop the technology? Note that unrestricted time travel is a form of FTL.

Finally, any time travellers will automatically start colonizing outwards at the speed of light from the point where they develop time travel. Contact with aliens in the future will guarantee this just so that the aliens encounter the time traveler's tech base ASAP so that they all can benefit from contact as much as possible. Even if they're short-sighted self-satisfied homebodies, they will at least send probes to other civilizations.