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Gamma-ray Bursts May Explain Fermi's Paradox
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.
Unchecked technology wipes out the technologists.
God created an oasis in the midst of chaos.
It was much later, he insisted I love you heathens.
And I do.
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.
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.
What part of "shall not be infringed" is so hard to understand?
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 normally made for the prevalence of complex life that would be millions or billions of years ahead of us.
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.
Silence is a state of mime.
Then God was zapped by a gamma-burst, that's why he has been never observed so far.
Achille Talon
Hop!
I'm not really sure what you are saying, but TFS is the CERN courier, reporting on an article in Physical Review Letters. I think your clickbait fears are more than a little unfounded.
Right, and a planet full of Hulks would kill itself off, supporting the gamma ray hypothesis.
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.
The problem isn't simple visits. The problem is twofold: no signs of communication and no signs of substantial change to the surrounding environment. We don't see any Dyson spheres or ringworlds or stellar lifting or any attempts at that all of which would be noticeable. If there are civilizations out there they are ignoring massive amounts of resources. Note also that in the scale of a few billion years travel and colonization isn't that big a deal: galaxies are only around 100,000 light years across so even going at 1% of the speed of light and hopping between stars should lead to galactic colonization within a a few hundred million years at the most.
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.
http://arxiv.org/abs/1409.2506 (not behind paywall)
Looking at space, radio, science and computing from a 'down-under' amateur enthusiast perspective.
The abstract doesn't say how bad it is to be hit by a GRB beam. GRBs don't last for more than a couple of minutes. It seems that would fry the side of the planet facing the GRB, but the other side would be shielded from much of the radiation. So you zap half the lifeforms and maybe you boil some ocean. No doubt it's unpleasant on the dark side, but is it lethal?
Fiat Lux.
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 planning, travel, etc, but you could get there. That's the nearest planet.
Now don't consider distance, etc. necessarily. Consider resources. Now you have to find the time, money, resources, engineering, etc. in order to make fuel to make the next jump. That's not easy at all. Hell, Mars is being talked of as one-way at the moment. And if we got to there, to get to Jupiter would take even more resources, energy, etc. Now there are ways and means to cheat this, but they are slow, and not capable of sustaining human life along the way at the moment.
But let's say, on every planet we visit, we find a ready-built space-base with fuel and oxygen enough to get to the next planet. We land, breed like fuck, and it only takes 20 years - doing nothing else - to plan, fuel, and travel on to the next. That's nearly two centuries before you're heading out of solar system. And you're unlikely to be overtaken at any point, even if Earth finds an energy source 10 times more powerful in that time.
Asteroids - even less resources, even harder to land on, even more difficult to colonise. Let's say we fire out probes all the time we're doing this (ignore where the resources for these probes comes from).
The next star is 8 light years away. Let's assume every star is that far away from the next, every star has the same kind of planetary system, etc. It's going to take several centuries to get to the first. Several millennia to traverse a handful. Meanwhile, all the probes your sending out will barely hit the next star but let's say they hit 10 stars on the way out, and talk back instantly if they find something. We could cover a few hundreds of stars in that time.
Let's go mad... several millennia of this (we'll stick with c as the limit of physics, but that might obviously change - at that point, we'll reconsider Fermi's Paradox anyway!), and the entire race dedicated to populating a planet, building the infrastructure to convert every resource it has to nothing more than space travel "fuel" (of whatever kind), and their sons move on to the next planet, all the while sending out hundreds of probes. Every few centuries, they go to a new star.
That's, rounding UP, (10^4 years / 2 x 10^1) generations, 10^1 stars per millienia in each direction. The orders of magnitude wouldn't get near 10^8 at all.
Do you realise where that gets you? There are a hundred billion stars just in our galaxy. That's 10^11. It'd take thousands of millennia (millions of years) to do this at stupendous speed across the galaxy, stopping to do nothing else.
No doubt there'd be advances and speed-up, but you're still orders of magnitude in debt before you've colonised a galaxy sufficiently. And then you consider the number of galaxies - That's another 10^11 or thereabouts.
And then you add in real-life, where we aren't just able to do nothing but look for aliens. What you're suggesting is that, even if there was a civilisation just a few stars away from us (incredibly unlikely given what we can see), it'll take anywhere from centuries to millennia to discover them. Assuming speed-of-light all the way, and communicating with probes all the way, etc. it'll take longer than man has so far existed in a form capable of doing such things to actually make any kind of contact if only, say, 1% of the galaxy is habitable.
The numbers just get more ridiculous after that.
Now, of course, we're limited by our current knowledge. But that's the point. Our current knowledge says t
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.
The Fermi Paradox - that we don't see billion-year-old civilizations around us and we're not sure why - is a fact.
systemd is Roko's Basilisk.
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.
-- sudon't
Air-ride Equipped
99% of alien life can be undetectable for whatever reason. If 1% is expansionist, a representative of that 1% could colonize every star system in a galaxy the size of the Milky Way in less than 3 million years, a cosmic eye blink.
The Moore-Murphy Law: The number of things that will go wrong will double every 2 years.
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, life that's not located on a planet, etc.. Everything you have said about alternative habitats only strengthens the Fermi Paradox.
We're busy looking for microbes on Mars
Nobody is trying to solve the Fermi paradox by looking for microbes on Mars, because we're pretty convinced there's no civilization there. At best, discovering a microbe there might modify one term of the Drake Equation in such a way as to make the Fermi Paradox *more* puzzling. Not finding any microbe is, frankly, the null hypothesis so it wouldn't move the needle.
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 mass into gamma ray energy. But the prevailing theory that best explains the majority of the rest of them are a special class of supernova that emits a huge amount of its energy in two narrow jets. When those jets happen to be pointed in our general direction, they appear to be a GRB.
Some GRBs emit so much energy that for a while astronomers couldn't reconcile their energy output with the limits on their size: even total conversion of all the matter in an object of that size into energy seemed to be insufficient to generate the kind of energy a GRB produces. When it was discovered that supernova can sometimes emit jets rather than explode outward equally in all directions, that provided a way for something of that size to appear to emit more energy than possible. Astronomers were calculating the energy reaching us from the GRBs, and assuming the object sent that much energy in all directions. Astronomers now think we only see a small fraction of all GRBs that detonate, and most jet their energy in directions we can't see.