Gamma-ray Bursts May Explain Fermi's Paradox 237
An anonymous reader writes: A new study confirms the potential hazard of nearby gamma-ray bursts. It quantifies the probability of an event near Earth, and more generally in the Milky Way and other galaxies over time: "[Evolved] life as it exists on Earth could not take place in almost any galaxy that formed earlier than about five billion years after the Big Bang." This could explain the Fermi's paradox, or why we don't see billion-year-old civilizations all around us.
Or maybe it's because (Score:3, Insightful)
Unchecked technology wipes out the technologists.
Re:Or maybe it's because (Score:5, Funny)
Indeed. My theory is that many of those mysterious gamma-ray bursts are civilizations earning a Galactic Darwin award.
"Hey look, we can create mini anti-black-holes in our la ~ ^ & [NO CARRIER]
Re:Or maybe it's because (Score:4, Funny)
It does not wipe them out, each civilization reaches a point where its porn and virtual reality are sufficiently advanced.
"Hey look, we can create totally realistic sex partners in our virtu--- [ FAP FAP FAP FAP FAP ]
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Interestingly, I oftened wondered if it was in the interests of intelligent life to focus their "expansion" inward to cyberspace vs. outerspace; transcending their evolution via forgoing the flesh bodies to machines of silicon based computers (or some such). Meaning, we're looking in the wrong places.
There was a Charles Stross book like that. The population of the solar system was moving into progressive levels of virtual worlds and never really looked at exploring the universe (except for the main characters of the book). Still, their civilization was limited by actual matter and energy in the real world. I find it surpassing they wouldn't look at getting some of that from nearby solar systems as the tech was there to do so. The main characters of the book did so, but they started early with great fina
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That could indeed be at the heart of one of the solutions to the paradox. As a civilization becomes more individualistic and inward focusing, breeding might drop off to the point of extinction. Think about it, if you could live 10,000+ years and have all of your needs (including emotional) met by synthetic means, would you bother having children? How many people would give any thought to the species as a whole continuing if we were not forced to deal with each other?
This sounds remarkably like C.S.Lewis' description of hell in The Great Divorce.
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well, robosexuals should stay in the wiring closet, or at the workstation
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WTF (Score:2)
From TFS:
They further estimate that GRBs prevent complex life like that on Earth in 90% of the galaxies.
So, life possible on 10% of the galaxies means that those are none at all? What about our own one? This smells of clickbait.
Re:WTF (Score:4, Informative)
Re:WTF (Score:5, Informative)
From TFS:
They further estimate that GRBs prevent complex life like that on Earth in 90% of the galaxies.
So, life possible on 10% of the galaxies means that those are none at all? What about our own one? This smells of clickbait.
The Fermi paradox basically states that if life on Earth is the typical result of similar conditions, the probability is far higher that there are older, more advanced civilizations, and eventually on timescales far smaller than the universe has existed we should eventually have bumped into one of them as they spread throughout the galaxy, even the universe.
The paper suggests two effects of gamma ray bursts that alter that calculation. First, a given location was more likely to be exposed to a gamma ray burst at earlier times in the universe, when the population of large hot stars was higher and overall density of the universe was higher. Therefore, its possible that even though the universe is 14 billion years old during a significant percentage of that time the universe was too dense and the frequency of gamma ray bursts too high to allow a sufficiently high technological civilization to arise. That's why there aren't any really old civilizations, or alternatively why there are so few that they tend to be very far away statistically. Second, even after the universe had expanded enough to make gamma ray bursts less likely to completely sterilize all planets everywhere its still the case that most parts of most galaxies are still too dense to avoid getting hit by them.
So its possible the reason why we have not yet seen a very old highly advanced civilization is that the actual probability of one being old enough, and close enough, for us to have bumped into (or rather for them to have bumped into us) is a lot lower than we might assume, even if the conditions to initiate life are pretty common. Nearly all of them have been wiped out before they could advance to the point of being able to colonize on an interstellar level and avoid being driven to extinction by gamma ray bursts.
Re:WTF (Score:5, Interesting)
We used to wonder what in the hell was making these ultra-bright quasars; now we believe that they are "active" galactic cores which are in the process of forming a supermassive black hole in the centers. It's possible that two such black holes might form and orbit their mutual centers of gravity, but eventually they would merge. This merging is probably the source of the gamma ray bursts.
Planets couldn't form until enough hydrogen had been fused into metals and expelled by supernova. Complex life couldn't form until there were enough different heavier elements. It's at least possible that early races and civilizations were exterminated by GRBs when their galaxies were new; it's even possible that intelligent life formed near the Galactic core of our own galaxy before the supermassive black hole formed. (Larry Niven may have been right! Thrints!) They were all killed in the GRB when our own galaxy shined like a quasar. Now that the Milky Way has settled down into gentle middle age, other races can develop.
It may be unlikely, but it's possible that humans are the most advanced of these third-generation beings.
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We used to wonder what in the hell was making these ultra-bright quasars; now we believe that they are "active" galactic cores which are in the process of forming a supermassive black hole in the centers. It's possible that two such black holes might form and orbit their mutual centers of gravity, but eventually they would merge. This merging is probably the source of the gamma ray bursts.
Most GRBs have a signal that's inconsistent with that scenario because of the size of the black holes: basically most GRBs have signals consistent with much smaller objects than galactic black holes.
The original theory, and one which still explains some GRBs, are the gamma ray emissions from two neutron stars merging. Binary stars are common, and in some cases both stars eventually become neutron stars. When their orbits decay, they can merge to form black holes and in the process convert a huge amount of
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There was a book a while back, "Rare Earth", that touched on a lot of these issues. One of the possible conclusions is we may actually be the first intelligent species to hit space flight in our galaxy. At some point there has to be a first after all.
I hope we are the first. Otherwise we Terrans would end up being second class citizens of the galaxy.
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Reminds me of a Babylon 5 quote
" There are things in the universe billions of years older than either of our races. They are vast, timeless. And if they are aware of us at all, it is as little more than antsand we have as much chance of communicating with them as an ant has with us. We know. We've tried. And we've learned we can either stay out from underfoot, or be stepped on."
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"That's why there aren't any really old civilizations"
The GRBs don''t really explain anything. Because it leads to the question why any civilization would need 1 BILLION years to develop the technology ot withstand a GRB. Maybe it would explain why life hasn't evolved beyond the microbial level. But once a civilization has achieved the Iron Age of technology, such a civilization is likely to achieve space faring status within a thousand years, unless of course they wipe themselves out or get struck by a far
Re:WTF (Score:4, Informative)
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Fermi assumes all would be as weak as we are and just drop dead
The Fermi paradox assumes no such thing. This guy's explanation of the Fermi paradox does -- and the fact is, that's a valid assumption *until* such life becomes sufficiently advanced. The idea is that maybe these things happen so frequently that no species can become sufficiently advanced between apocalyptic gamma ray bursts.
Two, Fermi and basically all other astrobiological research areas focus on the idea that life exists only on planets, generally single planets similar to our own existence in this star system.
No, it says that what we know of the probability of intelligent life seems to be so shockingly high that we should be able to find it without even bothering to look for exotic life,
That might explain it. But it is more likely that (Score:2)
God created an oasis in the midst of chaos.
It was much later, he insisted I love you heathens.
And I do.
Re:That might explain it. But it is more likely th (Score:5, Funny)
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Relativistic effects of being the singularity.
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Not really. (Score:5, Interesting)
This does not really resolve fermi's paradox. It just helps define fermi's paradox.
The human race has been in mostly the same state physiologically for more than 10,000 years-- That is to say, you could clone a person who lived 10,000 years ago, and never tell them their origins, and they would integrate into our society without problem.
Our civilization has been prevented from leaving the earth by our own silliness. Our big push out of a major duldrum of ignorance has been a bittersweet one; After the renaissance, we discovered that we were capable of much more than we had. We focused on that, and coined a now much maligned term: "Progress."
For the better part of the past 2 centuries, humans were focused on attaining such "Progress", and technological advancement grew at previously unprecedented speeds. We literally went from covered wagons and horses to nuclear power in 200 years.
It wasn't biology holding humans back from this rapid achievement-- It was attitude and social conventions. Things like warring over who's god has the biggest dick, or over who has the most money. (Things we STILL fight about to this day!) When there is a major social focus to improve, we have historically demonstrated the ability to do it.
If we can thus do this-- Go from horse drawn conveyances to nuclear energy in 200 years-- then there is very little reason to expect other potential civilizations from doing so as well, and perhaps not having spent quite as much time arguing over who's god has the mightiest member.
Yet, when we look up into the sky, we dont find any. We strain with our radio telescopes, and hear only the strange EM flux of gas giants, the hissing and popping of stars, and the screams of magnetars.
This finding does not settle Fermi's paradox. It just sets a slightly smaller boundry.
Re:Not really. (Score:5, Insightful)
First, it doesn't explain Fermi's Paradox, it merely adds another term to it. In all of those various probabilities, apparently there is something like a 10% chance of not getting taken out by a gamma burst in half-a-billion years. I would also expect the odds to get better as a given galaxy "settles down", generating fewer big, hot stars and more smaller, calmer ones. Some neighborhoods are probably rougher too. I wouldn't wait around to settle Trantor, near the center of our galaxy.
Second, I wouldn't consider intergalactic contact in any serious way - the distances are bad enough for interstellar, do we really want to add a few more orders of magnitude?
Third, our presence establishes our galaxy as one of the more benign ones. There is at least one neighborhood that has been sufficiently peaceful for the last half-billion hears. Last I knew, there were no supernova candidates close enough to cause that kind of trouble any time soon, either.
Fourth, I'll focus on your word "silliness", which I think you meant as an understatement. There is conceivably a chance that we are under observation, and rank as "too silly" for any contact. The Earth has had an oxygen atmosphere for the last half-billion years, and we're on the verge of being able to detect other such atmospheres on other worlds such as Kepler has found. It's not a bad assumption that any civilization capable of interstellar travel is also better at planetary surveys than us. If they're there and within a few thousand light-years, they know something worth seeing is probably here.
At this point in physics we're stuck at the Standard Model. We have many theories that move beyond, but no facts to select among them, and many of the experiments would be incredibly expensive. But let's say one day we saw a "warp signature", it's quite possible that we could immediately discard half of those theories. (By "warp signature" I really mean physical evidence of truly advanced technology.) IF there were here watching us, and seeing our "silliness" as well as the scientific acumen of some, they would be especially careful that we see no such evidence.
Re:Not really. (Score:5, Informative)
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So, basically, the aliens are the kind of assholes who would watch someone get into trouble and do nothing to help them get out? Gotcha.
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Re:Not really. (Score:5, Interesting)
First, us humans prefer killing each other to science. This is a proven fact.
Second, humanity did not go from Horses to Nukes, a very very small percent of the population did it, those geniuses have everyone else standing on their coat-tails.
The next leap will be by a very small group that is significantly more enlightened than the rest of the 99.95% of the population. If those people are benevolent, then everyone enjoys the fruits. If they are not....... Well, things can go very differently.
Currently with how education is going, the general population is becoming more uneducated every year. WE do not glorify learning, but instead glorify morons that can carry a ball, or can sing a tune. And we Vilify in society those that do love learning and are very smart.
Honestly Humanity is a joke, almost a cancer. And if an advanced civilization stumbled across us, they would probably wipe us out to make the rest of the universe safer. We as a species love to hate others, we love murder, war, and control. WE thrive on hating those that are different or think or worship different.
I think you're America-culture centric (Score:5, Interesting)
Some of the Asian countries do have cultures that love learning and the very smart. However, they have various other cultural problems.
There's this old joke, heaven is English policemen, German scientists/engineers, Italian lovers, Swiss bankers, and French cooks. Hell is English cooks, German policemen, Italian bankers, Swiss lovers, and, well, I don't suppose French make bad scientists/engineers, but I'm botching the joke some. But the point is that if we could take the very best of all our cultures and fuse them, humanity would advance far faster.
The Chinese have admirable work ethic and love of learning, however, their government needs improvement in inclusiveness and combating corruption. Some of the European governments are far superior in these respects (or so it seems from the outside.) The anti-intellectualism of the USA is rapidly degrading the US political system, its economy, its worldwide power, and its future prospect for maintaining dominance in science/tech/economy/military. However, again, not everywhere in the world does humanity glorify sports or singing and hate learning and intelligence.
Perhaps we can hope that the negative aspect of humanity will cause their own self-destruction without destroying the best aspects of humanity.
Re:Not really. (Score:5, Funny)
Honestly Humanity is a joke, almost a cancer. And if an advanced civilization stumbled across us, they would probably wipe us out to make the rest of the universe safer. We as a species love to hate others, we love murder, war, and control. WE thrive on hating those that are different or think or worship different.
You're right. We should find all those ignorant, warlike motherfuckers and kill them.
Re:Not really. (Score:5, Insightful)
Really? How did the arrangements for that experience go? Subject gets to choose between a test tube or a bound assistant and a (hopefully fake) knife?
A small part of the population did experiments on uranium, while the rest mined that uranium, enriched it, built the roads that carried it from the mine to the lab, etc. Accusing a tailor of riding on the coattails he made is rather absurd.
The invention to trigger the next leap will be by some group that is supported by others, allowing them to focus on something besides where their next meal will come from. After it has been made, it will be turned into something actually usable by other people, manufactured by yet others, distributed by yet other people along communication and transfer infrastructure built by, you guessed it, other people...
Heroic fantasies are just that: fantasies.
People respect people who can provide something useful, be it entertainment, a focus for a cultural bonding event, or a cure for cancer. If you aren't respected as much as you think you deserve, it's usually because you aren't doing anything to earn it. Merely being smart and learned is no more worthy of respect than being richr; it's what you're doing with it that earns - or doesn't - the respect.
Humans, in general, love thinking they're better than someone else, since that's easier than self-improvement. Sometimes that manifests as merely dismissing the entire species as "riding on the coattails" of a special few ubermenschen, and sometimes the delusion reaches the point of wanting to get rid of some specific group of perceived parasites. Either way, it's bullshit.
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I never once said anything about myself. You may wish to examine your biases, the errors in interpretation they cause and whether these errors make you significantly less effective at achieving whatever goals you have.
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Humans have been fighting and killing one another ever since there were enough people to pick sides. It most likely began with a cavemen wielding a club and waving a sharp piece of flint to get a nicer cave and better women. The fact we pretty much fight over the same reasons today leads one to wonder whether confrontation, aggression, and violence is built into human DNA. Are we just hardwired for aggression, confrontation, and violence? I suspect that without those built-in traits the human race would hav
You simply the problem far too much (Score:2)
Bullshit : energy and distance requirement belie this.
Look at the energy we have to expand to get out in LEO now. Even counting that and assuming you have a refuelling station , look at those requirement to go at 0.1%c speed and have enough fuel to brake. Even getting something like 0.1% C would be difficult. And at the distance we are speaking 0.1% c means thousand of years of travel. At such timescale, the GRB would st
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Is your reading comprehension broken?
The point was that humans went from just one step above agrarian culture, to nuclear power in 200 years, out of a possible period of 10,000 years in which that rapid progress could have happened.
This means that just looking at our own species as the model, we could have been at our current level of technology thousands of years ago, had we decided that waving our dicks around and arguing over gods and politics was less important than improving ourselves through discovery
Re:Not really. (Score:4, Insightful)
You need to study up on the history of technology and civilization, steady stream of advances were made over thousands of years not hundreds, including the widespread use of written language four thousand years ago.
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You are confused, those early examples found in Pakistan for instance were NOT widespread and thus not the adoption of writing by mankind. Those are examples of an idea that was tried and then lost again.
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Technological progress has been much more continuous over those 10,000 years. It didn't jump from Sumerian technology to nuclear power in just 200 years. Metallurgy (copper, then bronze, then iron, then steel), the wheel, use of coal, glassblowing, Euclidean geometry, algebra, trigonometry, calculus, physics, astronomy, chemistry, windmills, the Lateen sails, compass, telescopes, microscopes, a place-holding number system, movable type printing presses, gunpowder weapondry, the arch and dome, aqueducts, c
Re: Not really. (Score:5, Interesting)
Total bollocks.
Nuclear propulsion could easily lift hundreds of thousands (perhaps millions) of tonnes of cargo into space, and had been demonstrated at near full scale. See NERVA and Project Orion, both of which were so technically successful that congress canceled them as to avoid having to fund true space colonization and development.
Nuclear propulsion also has the potentially to travel at relativistic speeds, potentially allowing travel to near by stars within a human lifetime.
I quote, "The reference [Orion] design was to be constructed of steel using submarine-style construction with a crew of more than 200 and a vehicle takeoff weight of several thousand tons. This low-tech single-stage reference design would reach Mars and back in four weeks from the Earth's surface (compared to 12 months for NASA's current chemically powered reference mission). The same craft could visit Saturn's moons in a seven-month mission (compared to chemically powered missions of about nine years)." (Wikipedia)
It's not my fault that politicians have decided that space propulsion should not advance significantly beyond chemical power, effectively being stupidly big and advanced firecrackers.
This is not new technology, this was developed in the 50s and 60s. Has development continued, I have no doubt that we would have industrial space stations, reasonable interplanetary travel (as in weeks/months instead of years/decades), and man would currently be planning to launch a multimillion ton expedition from the asteroid belt to nearby stars with confirmed exoplanets. The only reason we don't take advantage of space resources, and zero gravity manufacturing is because it takes $20000+ per kilo to get a payload into orbit. Drop that to $500, and everything changes dramatically.
The problems with real space exploration are speed and payload mass limitations. Nuclear energy solved both of these problems decades ago.
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You don't get relatavistic velocities with fission or fusion propulsion at reasonable mass ratios. You need antimatter for that.
Re: Not really. (Score:5, Informative)
Total bollocks? :)
There's one thing nuclear propulsion cannot do, and that's exactly what you claim it can do in your opening sentence: lift that payload from the surface to orbit.
Project Orion would be using a long series of nuclear explosions to almost literally hammer the spaceship forward. You're proposing that as a LIFTOFF engine to be used within the atmosphere?
Quoting from the same wikipedia page, one of the reasons why the project was shut down:
"There were also ethical issues with launching such a vehicle within the Earth's magnetosphere: calculations showed that the fallout from each takeoff would kill between 1 and 10 people."
That's from launching within the magnetosphere, not even close to launching from the surface.
Yes, total bollocks, clearly :)
Re: Not really. (Score:4, Insightful)
So the environmental and health impact would likely be much greater than 1-10.
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That is why we stopped using coal years ago right?
1-10 is small in comparison to the deaths from coal, and even less attributable.
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It is easy to paint a rosy picture of what might have been when something does not even get past the drawing sta
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We barely have technology within our lifetimes to get one man to Mars on a suicide mission. Even if you pored all the resources of all mankind's wars it would barely be better and that's just to the nearest planet
We have the technology within our lifetimes to send multiple people to Mars on an extended scientific research mission and return them safely to Earth. What we lack is the will to expend our resources on such an endeavor.
That said, interstellar travel is orders of magnitude more difficult.
Fermi's Paradox.. wait (Score:2)
I thought gamma rays explained The Incredible Hulk?
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Right, and a planet full of Hulks would kill itself off, supporting the gamma ray hypothesis.
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Hulk is invincible
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So then we have a Universe full of Hulks waiting for us out there.
Why would they want to colonize the galaxy? (Score:2)
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The scale just doesn't compare (Score:2)
There was still plenty of room left in Europe when pilgrims settled in America.
You're assuming that the task of crossing the Atlantic in the 17th Century is a feat comparable to a more advanced civilisation travelling dozens of lightyears in space. We are a more advanced civilisation - and not only are we still doing pretty badly at human space exploration, we're staring to form pretty successful scientific theories that show the task will be very, very difficult - and could be impossible. You're basing your argument on the (non-falsifiable) notion that an advanced civilisation will
Fermi's paradox is hubris (Score:3)
Regardless even if billion year old civilizations do exist, as posted above, there may well be hard physical limits on expansion due c etc. And just listening for radio evidence is unlikely, both due to distance, and the fact that out own radio window (and any other species) is likely to be short. already more and more of our radio transmissions are low power and directed. This will only continue, reducing our emissions, Listening for any leakage from a great distance is akin to trying to smell a fart in a hurricane.
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We already are surpassing radio to become something that is undetectable in space. spread spectrum and low power communications is already common place in the Ham Radio community. with 2.5 Watts I can talk to 30 people around the globe using PSK31 or Wspr. My signal will not be detectable past the moon even on the best radio equipment made. High power broadcasting is a thing of the past and will rapidly disappear. Some of these new technologies will make communicating with our own space probes easier,
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with 2.5 Watts I can talk to 30 people around the globe using PSK31 or Wspr.
I've got that record beat at least on WSPR. I xmitted on 30m using 100mW from central VA (grid FM17), and was heard in New Zealand. An amazing mode, isn't it?
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And WSPR is only the beginning, there are other modes coming down the pipeline that are almost magical/spooky. pulling useable information out of what seems to be background noise.
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That a similar setup pointed at the exact location can detect. guess what, that doesn't work well even here on the planet. Point to Point Dish based directed communication is a bitch to get working in insanely small distances like only 10 miles. So we shoot a signal at a single cluster, did we do it for years on end? nope. so nobody will hear anything.
What you have to do is a wide insane power broadcast to cover the entire sky. Broadcast 24/7 for 10 years. That way not only do you have informatio
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The speed of light puts no barriers on expansion, only - give us a few million years with technology we already have the early stages of and we could colonize the galaxy without trouble. And if we colonized a world around one of the many stars being expelled at high speeds towards a distant galaxy then in a few hundred million years we could start all over again there.
Also, Fermi's paradox makes no assumptions about the endgame of evolution - the phrase is itself nonsense: evolution has no goal except repr
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Okay, granted - at *that* scale, yes there are some limits. But the further you go into the past the less constricting those limits would have been.
I also seem to recall that at the galactic cluster scale, and possibly even at the supercluster scale, galaxies will remain gravitationally bound to each other rather than being pulled apart by expansion, so that's 54+ galaxies in our local group that will remain accessible. And if the Virgo supercluster is strongly enough bound, that means there will be at lea
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Intelligence is the ultimate evolutionary adaption, I believe that life inevitably tends towards higher and higher levels of it. Consider, we're ill suited for anything but temperate climates in our bare skin, and even then we'd make easy prey for predators, being neither fast nor especially strong.
Add a sprinkle of intelligence and suddenly we're wearing animal skins in the cold, building fires at night, and protecting ourselves with spears.
Intelligence is absolutely a survival trait, perhaps the most powe
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Intelligence is essentially the ability for a species to drive their own adaptation, and do it far faster than mere biological evolution ever could. It certainly is immensely powerful. I don't think life inevitably trends that way though, because evolution doesn't really trend in any direction but that which allows a species to continue to reproduce.
Consider, if evolution tended to move towards higher intelligence, we would expect the oldest species to be the most intelligent. We would also expect to see an
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Some good points there. I think in a stable environmental niche, intelligence would never develop, most of the oldest species have been in such niches as long as they've been around. However that an entire biosphere which remains permanently environmentally stable exists out there is something I find difficult to credit. I mean sure it's possible but the universe is a tumultuous place.
In such changing environments adaptability is king, and intelligence is the best enabler of adaptability.
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No doubt that intelligence has been proven to be immensely valuable, after all it is the single factor that has led to the dominance of humans on Earth. My point, though, is that there are a lot of "local minima" where it isn't going to develop because it doesn't offer advantages in certain niches. It also does come at a hefty evolutionary price - we need a high level of activity and high caloric intake to support our brain's resources, and our young are helpless for many years after being born because that
Gamma-ray bursts extinctions not likely any more (Score:2)
While studies show that a gamma ray burst most likely hit the earth causing the "The Ordovician–Silurian extinction events"= http://en.wikipedia.org/wiki/O... [wikipedia.org]–Silurian_extinction_events. The extinction occurred 443.4 million years ago, during one of the most significant diversifications in Earth history."
Yet we survived as an intelligent life form.
Or survival has been protected in no small way by the fact were in a fairly unpopulated spiral of the galaxy. The closer to the center of the galaxy,
Not advanced (Score:2)
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If everyone is as smart as Bruce Banner then I would expect warp drives to be developed quite fast.
arXiv:1409.2506 (Score:3)
http://arxiv.org/abs/1409.2506 (not behind paywall)
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How lethal are GRBs? (Score:5, Interesting)
Re:How lethal are GRBs? (Score:4, Informative)
There are some articles on the internet about this. Basically: one side would be fried, the atmosphere would be superheated, and you would have nasty smog all over earth afterwards, making sure that seeds wouldn't grow because Earth would be pretty dark. Oh, and the ozone layer would be stripped off, so the bottom of the ocean might be survivable but apart from that you'd want to be underground during daylight.
In 2008 there was a GRB that occurred about 7.5 billion lightyears away - it was visible with the naked eye, and was aimed straight at Earth. Just imagine what something at 75000000 million lightyears would do - let alone at 7500, about where WR104 is.
Fermi's Paradox option #5: We're running in a VM (Score:2)
http://io9.com/11-of-the-weird... [io9.com]
But yes, there could be all sorts of hazards out in space we are unaware of and have been very luck to avoid. Including "Galactic Superwaves":
http://starburstfound.org/gala... [starburstfound.org]
It's Not a Paradox (Score:3)
It's not a paradox if life is unique to Earth. This idea that, because there are trillions of stars, and because many of them have planets, ergo, there must be life on many of them, is a statistic based upon a sample of one. Until we understand how life began, I don't know if we can really say anything about the chances of life elsewhere. It's pure speculation.
Re:Simple Explanation (Score:5, Insightful)
More simple explanation: Life is out there, it's just too far away to detect, or to visit us--and will ALWAYS be so, because you can't cheat Newton and Einstein. An alternate "simplest" explanation (though less likely) is that we are first.
To suggest that ET hasn't come to visit us because we are "too violent" or whatever, and that they are masking their presence is definitely NOT the simplest explanation--it suggests that every nearby alien species has agreed to isolate us, and every member of those civilizations is on board with the idea. No one is out there playing with an RF emitter in the VHF band, Harry Mudd hasn't stopped by and spilled the beans, no one's even accidentally done anything to give the game away.
Sorry, I'm just not buying that.
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You don't have to cheat Einstein to populate the galaxy. Nanotech based Von Neumann machines could easily spread out and cover our galaxy in a million years, the technology is certainly not impossible, indeed it is likely to be developed in the relatively near future should we decide to do so, and the possibility to live indefinitely in mechanical or biological bodies does not seem to be impossible either.
What could we do in a 1000 or 10,000 years. The Fermi Paradox is entirely valid given the assumptions n
Travel is hard, Radio is not (Score:2)
An alternate "simplest" explanation (though less likely) is that we are first.
Just curious but why do you say that? We have no clue how likely intelligent life is to evolve. All we know is that it has happened once, and it took 3.5 billion years from the formation of the first like on Earth. Suppose that this was very much faster than average and the the mean time for intelligent life to evolve (once life itself has started) is 30 billion years? Such a long time would hugely reduce the number of intelligent species since you need a very stable environment for a long period of time a
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I guess it is the simplest approach. If you have one data point only and you expect a normal distribution [age of the civilization on the x-axis] then it is more probable our data point falls around the middle. It can be at the beginning [fist civilization] it is just less likely...
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then it is more probable our data point falls around the middle
My point is though that without knowing the width of that distribution you have no idea how wide the 'middle' is: if your average time to evolve intelligence is 30+/-20 billion years we are still well within 2 sigma from the mean. This could make intelligent life sufficiently rare so that we could easily be the first in our galaxy given the age of the universe. With billions of galaxies there could still be more advanced intelligent life in a galaxy far, far away but we would never know about them.
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For the sake of speculation -- what would be humanity reaction to a message? What about a visit? I hear study after study saying we will panic and that "people are not ready". Not that reality asks if you are ready but anyway....why are we not ready? I know I am ready...even eager to meet the aliens....yet we get those statements even from famous scientist that are in my opinion ridiculous. Like Hawking's warning that they'd take our resources which is soooo funny...imagine the aliens crossing interstellar
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Just remember, that those 1-in-a-billion odds are based on a number of assumptions. For starters there were, if I recall correctly, at least a half-dozen different species of "humans" that evolved on this planet from early proto-humans. Virtually all whales are candidates for being intelligent life, though very different from our own. They're undeniably tool users, though the lack of grasping appendages severely limits tool-making. Elephants are pretty damned smart as well. Parrots have been documented
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Do you mean technological civilizations? Because whales have a pretty sophisticated globe-spanning culture.
My point was more that there's lots of candidate species that, in the right circumstances, might have potential to cross whatever threshold it is that we crossed. And the evidence suggests that at least most other human species went extinct as a result of our own expansion, had we not evolved one of the other variant would likely have become the dominant species instead.
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Whales appear to have social stratification and symbolic communication (spoken language) - the others are of course more problematic for a species without hands, and far better evolved to live in comfort in a much more bountiful environment. Though being basically unchallenged apex predators with a globe-spanning communication system allowing them to coordinate between remote "tribes" could be interpreted as providing separation and domination over their environment. But that lack of hands and natural long
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Yeah, I suppose they might, if they were discovered within rock that gave some sense of their actual age. Otherwise they would almost certainly be credited to earlier civilizations of the new species, no doubt confounding their equivalent of anthropologists with the extreme precision with which they were cut. Might even help inspire a lunatic fringe convinced that aliens had visited Earth in the past.
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There is no conclusive evidence that there even exists such a thing as interplanetary travel for a life-form. We've barely touched the moon ourselves.
Now, granted, the acceleration from the beginning of the last century to the Moon-missions was extraordinary. But since then, if anything our acceleration has slowed to an absolute crawl. The expense of a simple one-off mission that we've already done several times just isn't viable any more.
Now, consider, that you could get to Mars. It'd take decades of p
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Oops, typo: Assume an average spread of one light year every 10000 years and an intelligent species has the entire galaxy covered in 1 billion years.
Re:Speculations become facts now? (Score:5, Insightful)
The Fermi Paradox - that we don't see billion-year-old civilizations around us and we're not sure why - is a fact.
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What's uncertain about the fact that we don't see billion-year-old civilizations around us?
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As for your scientific 'paradox', that is not really a paradox, more of a straw man.
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First gen stars didn't have any rocky planets nor enough metals to form cellular life. If they had life it would have to be quite different to us.
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I seem to recall third, but the stars that make and scatter medium-weight elements are big bright short-lived ones, so the first generation might only have taken 10 million years. There is some uncertainty about where the heavier elements (gold, uranium, etc.) come from. It is possible they are produced by a much rarer process.