Posted on 08/26/2013 4:29:42 PM PDT by LibWhacker
(Phys.org) —Scientists as eminent as Stephen Hawking and Carl Sagan have long believed that humans will one day colonise the universe. But how easy would it be, why would we want to, and why haven't we seen any evidence of other life forms making their own bids for universal domination?
A new paper by Dr Stuart Armstrong and Dr Anders Sandberg from Oxford University's Future of Humanity Institute (FHI) attempts to answer these questions. To be published in the August/September edition of the journal Acta Astronautica, the paper takes as its starting point the Fermi paradox – the discrepancy between the likelihood of intelligent alien life existing and the absence of observational evidence for such an existence.
Dr Armstrong says: 'There are two ways of looking at our paper. The first is as a study of our future – humanity could at some point colonise the universe. The second relates to potential alien species – by showing the relative ease of crossing between galaxies, it makes the lack of evidence for other intelligent life even more puzzling. This worsens the Fermi paradox.'
The paradox, named after the physicist Enrico Fermi, is something of particular interest to the academics at the FHI – a multidisciplinary research unit that enables leading intellects to bring the tools of mathematics, philosophy and science to bear on big-picture questions about humanity and its prospects.
Dr Sandberg explains: 'Why would the FHI care about the Fermi paradox? Well, the silence in the sky is telling us something about the kind of intelligence in the universe. Space isn't full of little green men, and that could tell us a number of things about other intelligent life – it could be very rare, it could be hiding, or it could die out relatively easily. Of course it could also mean it doesn't exist. If humanity is alone in the universe then we have an enormous moral responsibility. As the only intelligence, or perhaps the only conscious minds, we could decide the fate of the entire universe.'
According to Dr Armstrong, one possible explanation for the Fermi paradox is that life destroys itself before it can spread. 'That would mean we are at a higher risk than we might have thought,' he says. 'That's a concern for the future of humanity.'
Dr Sandberg adds: 'Almost any answer to the Fermi paradox gives rise to something uncomfortable. There is also the theory that a lot of planets are at roughly at the same stage – what we call synchronised – in terms of their ability to explore the universe, but personally I don't think that's likely.'
As Dr Armstrong points out, there are Earth-like planets much older than the Earth – in fact most of them are, in many cases by billions of years.
Dr Sandberg says: 'In the early 1990s we thought that perhaps there weren't many planets out there, but now we know that the universe is teeming with planets. We have more planets than we would ever have expected.'
The Acta Astronautica paper looks at just how far and wide a civilisation like humanity could theoretically spread across the universe. Past studies of the Fermi paradox have mainly looked at spreading inside the Milky Way. However, this paper looks at more ambitious expansion.
Dr Sandberg says: 'If we wanted to go to a really remote galaxy to colonise one of these planets, under normal circumstances we would have to send rockets able to decelerate on arrival. But with the universe constantly expanding, the galaxies are moving further and further away, which makes the calculations rather tricky. What we did in the paper was combine a number of mathematical and physical tools to address this issue.'
Dr Armstrong and Dr Sandberg show in the paper that, given certain technological assumptions (such as advanced automation or basic artificial intelligence, capable of self-replication), it would be feasible to construct a Dyson sphere, which would capture the energy of the sun and power a wave of intergalactic colonisation. The process could be initiated on a surprisingly short timescale.
But why would a civilisation want to expand its horizons to other galaxies? Dr Armstrong says: 'One reason for expansion could be that a sub-group wants to do it because it is being oppressed or it is ideologically committed to expansion. In that case you have the problem of the central civilisation, which may want to prevent this type of expansion. The best way of doing that get there first. Pre-emption is perhaps the best reason for expansion.'
Dr Sandberg adds: 'Say a race of slimy space aliens wants to turn the universe into parking lots or advertising space – other species might want to stop that. There could be lots of good reasons for any species to want to expand, even if they don't actually care about colonising or owning the universe.'
He concludes: 'Our key point is that if any civilisation anywhere in the past had wanted to expand, they would have been able to reach an enormous portion of the universe. That makes the Fermi question tougher – by a factor of billions. If intelligent life is rare, it needs to be much rarer than just one civilisation per galaxy. If advanced civilisations all refrain from colonising, this trend must be so strong that not a single one across billions of galaxies and billions of years chose to do it. And so on.
'We still don't know what the answer is, but we know it's more radical than previously expected.'
On the other hand, there seems some connection of the chemical reproduction of certain clay minerals and the biological reproduction of species?
I think it’s all terrestrial.
...After God....
I always had this thought where by the time civilization has split the atom, the clock is ticking to whether they will be able to take off from their planet or they will collapse at some point. Since World War II, we have been in that race. I can’t say for certain but I am convinced that civilization might have risen once or twice prior to our and then they collapsed. It reminds me of the book, “A Canticle for Leibowitz.”
Who's talking about time travel?
The Alcubierre “Warp Drive” isn’t physics; it’s fiction.
So was heavier-than-air manned flight, until the Wright brothers did it. Landing men on the moon was widely ridiculed at one time, because it seemed so far-fetched.
You live in an age of technological marvels and breakthroughs. Things are yet to be invented that seem like pure science fiction to you today.
The Earth and the Moon are aligned in such a way that the Sun casts a total eclipse for us to see and understand that Einstein was correct.
Interesting coincidence don’tcha think.
___________________________________________________
What are the odds ?
You would think that some guys would have done the math ?
Oh, wait, they did the math.
Ok, so, that’s not important right now, we got a story to tell.
A lot of hard archaeological evidence has been found that supports that hypothesis, but most of it has been shut away in the basements and back rooms of dusty museums by politically correct scientists and researchers.
Can't upset the accepted order, ya know.
That was hillarious, those poor cats didn’t realize who they screwed with, lol.
A civilization intelligent enough to be able to contact us, would be smart enough to recognize the danger of broadcasting your position before you discover the capabilities and intentions of the other civilizations.
I think the great leap will come when we can mine and refine metals in space and build the very large ships we would need for deep space travel. Obviously we aren’t going to see anything approaching light speed in our lifetimes. Probably a few hundred years of expanding across our solar system with ships that can achieve maybe 10% of light speed.
The guy that wrote the book (literally) on Chemical reproduction, came out a few years later and destroyed his own hypothesis.
They still use his book.
Sad.
I believe it was Dean Kenyon.
Very interesting twist wasn’t it.
Maybe radio waves are as quaint as two cans a string to et???
Yes it was, I like the jaw dropping conclusion that the alien captain had at the end, WHAT HAVE WE DONE?
I think by the end of the next decade humans have pretty much taken over the galaxy at that point....
I agree.
I think you're right, but I'd put the timescale at closer to a hundred years hence - IF we can keep from blowing each other up in our petty squabbles back home.
We're in the so-called 'J-curve' of technological development now. The pace of discovery is literally straight up, and accelerating. The only things that can slow it down, are lack of will to push the boundaries forward, or outright suppression of actual advancements.
If we can somehow survive and overcome our specie's violent tendencies, we'll make it to the stars.
I've said for years that SETI is monitoring the wrong spectrum.
I had just never really thought of it from that direction before but it appears to be the way Turtledove writes all the time.
They could travel all across the galaxy at will but had zero understanding of anything above muzzle loading rifles.
With that being said, I don't believe for a second that we're the sole creation of God..........There would have been no reason for Him to stop with us......
The Deadelus project is the direction I think we’ll take.
http://news.discovery.com/space/private-spaceflight/tau-zero-project-daedalus-icarus-110119.htm
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.