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Post by auntym on Apr 2, 2014 11:35:29 GMT -6
www.space.com/25325-fermi-paradox.html What Is the Fermi Paradox?By Elizabeth Howell, Space.com Contributor April 02, 2014 The Fermi Paradox seeks to answer the question of where the aliens are. Given that our star and Earth are part of a young planetary system compared to the rest of the universe — and that interstellar travel might be fairly easy to achieve — the theory says that Earth should have been visited by aliens already. As the story goes, Enrico Fermi (an Italian physicist) first came out with the theory with a casual lunchtime remark in 1950. The implications, however, have had extraterrestrial researchers scratching their heads in the decades since. "Fermi realized that any civilization with a modest amount of rocket technology and an immodest amount of imperial incentive could rapidly colonize the entire galaxy," the Search For Extraterrestrial Intelligence (SETI) said on its website. "Within ten million years, every star system could be brought under the wing of empire. Ten million years may sound long, but in fact it's quite short compared with the age of the galaxy, which is roughly ten thousand million years. Colonization of the Milky Way should be a quick exercise." Plentiful planets It is true that the universe is incredibly vast and old. One estimate says the universe spans 92 billion light-years in diameter (while growing faster and faster). Separate measurements indicate it is about 13.82 billion light-years old. At first blush, this would give alien civilizations plenty of time to propagate, but then they would have a cosmic distance barrier to cross before getting too far into space. The sheer number of planets that we have found outside of our solar system, however, indicates that life could be plentiful. A November 2013 study using data from the Kepler Space Telescope suggested that one in five sun-like stars has an Earth-size planet orbiting in the habitable region of its star, the zone where liquid water would be possible. That zone is not necessarily an indication of life, as other factors, such as the planet's atmosphere, come into play. Further, "life" could encompass anything from bacteria to starship-sailing extraterrestrials. A few months later, Kepler scientists released a "planet bonanza" of 715 newly discovered worlds, pioneering a new technique called "verification by multiplicity." The theory essentially postulates that a star that appears to have multiple objects crossing its face or tugging at it would have planets, as opposed to stars. (A multiple star system at such close proximity would destabilize over time, the technique postulates.) Using this will accelerate the pace of exoplanet discovery, NASA said in 2014. Our understanding of astrobiology (life in the universe) is just at a beginning, however. One challenge is these exoplanets are so far away that it is next to impossible for us to send a probe out to look at them. Another obstacle is even within our own solar system, we haven't eliminated all the possible locations for life. We know from looking at Earth that microbes can survive in extreme temperatures and environments, giving rise to theories that we could find microbe-like life on Mars, the icy Jovian moon Europa, or perhaps Saturn's Enceladus or Titan. All of this together means that even within our own Milky Way Galaxy — the equivalent of the cosmic neighborhood — there should be many Earth-size planets in habitable zones that could host life. But what are the odds of these worlds having starfarers in their bounds? [Countdown: 13 Ways to Hunt Intelligent Aliens] www.space.com/20155-hunting-intelligent-aliens-extreme-seti.htmlCONTINUE READING: www.space.com/25325-fermi-paradox.html
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Post by auntym on May 8, 2015 14:02:34 GMT -6
www.universetoday.com/120146/animated-explainer-on-the-fermi-paradox-from-kurz-gesagt/ Animated Explainer on the Fermi Paradox from Kurz Gesagtby Fraser Cain May 7, 2015 WHERE ARE ALL THE ALIENS?Published on May 6, 2015
The universe is unbelievably big – trillions of stars and even more planets. Soo… there just has to be life out there, right? But where is it? Why don’t we see any aliens? Where are they? And more importantly, what does this tell us about our own fate in this gigantic and scary universe?
Videos, explaining things. Like evolution, time, space, global energy or our existence in this strange universe. We are a team of designers, journalists and musicians who want to make science look beautiful. Because it is beautiful. If you’re fascinated by the Fermi Paradox like I am, you’re going to want to spend a few minutes and watch this wonderful video from the Kurz Gesagt team. We’ve shared a bunch of their videos on the past about the Big Bang, the Solar System, and neutron stars. This video tackles the infuriating question: if the Universe is enormous, and ancient, and there seem to be planets capable of supporting life everywhere… where are all the aliens? After you’ve watched this video, go to their channel and go down the rabbit hole and watch all their videos. www.universetoday.com/120146/animated-explainer-on-the-fermi-paradox-from-kurz-gesagt/
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Post by swamprat on Jan 9, 2021 10:37:39 GMT -6
Plenty to think about!What is the Dark Forest Theory? How doesn’t it relate to the Fermi Paradox?By Steve Baker, Blogger at LetsRunWithIt.com (2013–present) Updated June 23, 2020
It’s one possible solution to the so-called paradox that Fermi put forward…and it most certainly does relate to it. But this is a hypothesis within a hypothesis within a hypothesis: • The Drake equation is a good way to try to estimate the number of intelligent species in the galaxy. But a lot of the terms in it are very hard to estimate - so it’s kinda useless until we have more data. • The Fermi paradox (in effect) plugs in numbers into the Drake equation that are really dubious - comes up with a large number for the probability of us being visited by aliens and then says that it’s a paradox that we have not been. Since the numbers it provides into the Drake equation are unsubstantiated…it’s not a paradox. One of the numbers is wrong. • The Dark Forest hypothesis says that the reason we don’t see aliens is because every single alien species is so greatly concerned about other species attacking them that they dare not reveal themselves.
HENCE: • Dark Forest is saying that the solution to the paradox is that ONE of the numbers plugged into the Drake equation is wrong. But why not any of the other numbers? • The Fermi Paradox isn’t a paradox in the first place - it’s just bad guesswork for the numbers in the Drake equation. • The Drake Equation may not even be correct if there are confounding factors that it may not consider. It’s not mathematical proof or anything. It’s just a way to discuss what we know (like what percentage of stars have planets) and what we don’t know (like what is the probability of abiogeneis).
So this is a triple layer cake of vague ideas - and the Dark Forest Hypothesis is the top (and most wobbly) of those layers. It’s a pretty useless contribution to the general discussion of alien life.
BUT I GUESS WE HAVE TO TALK ABOUT IT ANYWAY: Soooo…. Dark Forest says that NOBODY talks because they’re scared - and therefore NOBODY finds out whether anyone else exists. It’s a somewhat plausible theory - but it’s badly shaken by the indisputable fact that we humans have gone around broadcasting and narrowcasting messages to nearby stars - sending out deep space probes with convenient maps to our location etched into them - sending out “Welcome” messages in 130 languages…that kind of thing!
So this concept just exchanges one paradox (Why don’t we hear from any alien species?) with a new one (Why are humans the only species who aren’t too scared to send out messages?).
This might be the case - but it’s a terrible “solution” to the Fermi paradox. By far the simplest explanation is that life is so rare that none of the other species are in radio range of us. But you can basically pick any of the unknown terms in the Drake equation and set it to a small enough value - and you have another potential solution to the Fermi paradox.
The Drake equation multiplies together the following terms: 1. R∗ = the average rate of star formation in our galaxy 2. fp = the fraction of those stars that have planets 3. ne = the average number of planets that can potentially support life per star that has planets 4. fl = the fraction of planets that could support life that actually develop life at some point 5. fi = the fraction of planets with life that actually go on to develop intelligent life (civilizations) 6. fc = the fraction of civilizations that develop a technology that releases detectable signs of their existence into space 7. L = the length of time for which such civilizations release detectable signals into space
We’re probably correct about R*, fp, and maybe…more dubiously, ne (presuming that being in the “habitable zone” where there can be liquid water - and being roughly earth-sized is both necessary and sufficient.
But we have no idea about fl (except that it’s not zero because we exist), we might hazard a guess about fi because (for example) the dinosaurs never seem to have developed intelligence - but yet we have some measure of intelligence in whales, elephants, octopus, grey parrots, ravens, etc.
fc can’t be zero (because we developed that technology) - but if Dark Forest is claiming that this number must be so infinitesimally small that we alone are the only ones not to scared to talk.
L is another unknown - it seems to be at least 100 years…but much depends on how strong those signals have to be and how hard we look.
So why home in on fc as being the tiny number? Why can’t the solution to the Fermi Paradox be (say)
• “Rare Moon”: The ne term is small because it turns out that life can’t happen without a large moon orbiting a small planet - and since our moon was formed by a seemingly VERY rare collision between two planets…that could be a tiny number. • “Self-Replication is unlikely”: The fl term is tiny because it requires random formation of protein chains by inorganic means of a self-replicating molecule. (This seems to me to be an insanely small number). • “Intelligence is rare”: The fi term is tiny because intelligence isn’t a very useful thing to evolve - and something unique about Earth is only reason our planet produced it. • “Dark Forest” could account for fc being small - but I can think of other reasons. Maybe intelligent life MOSTLY forms in places where radio communication isn’t useful or necessary. Maybe life forms in tiny villages who don’t talk much to each other for cultural reasons - so it’s easier to shout to your neighbor than use a phone? Maybe life forms mostly around stars that put out so much radio noise that radio is useless as a means of communication. • “Radio is like Flint hand tools” could account for L being small. Maybe there are much better forms of communication (quantum entanglement perhaps) that means that radio ceases to be useful…or maybe most civilizations move their intelligences inside vast computers with virtual reality - and so stop needing external communications after 200 years.
So Dark Forest is only one of at least five (and probably dozens) of other ways that the Fermi paradox can be broken.
To me it seems the least likely. If there are marauding alien armies who eat other civilizations who dare to communicate - how come we can’t detect THOSE civilizations?
Source: www.quora.com/
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Post by jcurio on Jan 10, 2021 6:54:18 GMT -6
or maybe most civilizations move their intelligences inside vast computers with virtual reality - and so stop needing external communications after 200 years. __________________________
I, was one of those strange people, who when the original movie “transformers” came out, felt a strange “ephinany”.
And I was glad that I was at home watching it; instead of a movie theater. I cried real tears. Metal objects “coming to life”?
??
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Post by auntym on Sept 1, 2022 12:29:52 GMT -6
thedebrief.org/the-paradox-of-fermis-paradox/THE PARADOX OF FERMI’S PARADOX by CHRISTOPHER MELLON / SEPTEMBER 1, 2022 “All this visible universe is not unique in nature and we must believe there are, in other regions of space, other worlds, other beings and other men.” – LUCRETIUS 99-55 BC Is it possible some UAP are extraterrestrial craft? Is it reasonable to think there is intelligent alien life visiting earth? Scientists still debate whether the universe is infinite, but at a minimum, our visible universe contains trillions of galaxies, each with hundreds of billions of planets and moons. As best we can tell, the same laws of physics apply everywhere, and the heavy organic molecules that form the basic building blocks of life are abundant. In short, from the nearest solar systems to the most distant edges of space and time, we are surrounded by endless opportunities for life. Amidst these endless opportunities, intelligent extraterrestrial life is a near mathematical certainty. But what about the prospects for intelligent life to evolve in Earth’s galactic neighborhood? Although estimates vary considerably, many indicate we are probably not alone in the Milky Way. Duncan Forgan, a Ph.D. Candidate in astronomy at the Royal Observatory in Edinburgh, Scotland, carefully evaluated data on the composition of the Milky Way and concluded there should be over 360 stable, advanced civilizations in our galaxy. He also believes that if microbial life can spread via meteors, we may be sharing the Milky Way with tens of thousands of technologically advanced civilizations. In 2020, astronomers Tom Westby and Christopher Conselice, researchers at the University of Nottingham, performed an extensive assessment of the latest astronomical data and concluded, within a band of uncertainty, that we share the Milky Way with dozens of other technologically advanced alien civilizations. Astronomers Adam Frank and Woodruff Sullivan took a somewhat different approach but reached similar conclusions. According to co-author Adam Frank, “Even if you are pretty pessimistic and think that you’d have to search through 100 billion planets in habitable zones before you found one where a civilization developed, then there have still been a trillion civilizations over cosmic history!” Even if life arises on habitable Earth-like planets only once in 60 billion opportunities, we are still not the first civilization in the Milky Way. As these and other astronomers have concluded, the existence of advanced alien civilizations in our galaxy is a good bet. Nevertheless, the Milky Way is hundreds of thousands of light years across. Could other civilizations in the Milky Way reach earth with probes or spacecraft? With what might appear to us to be UAP? The answer is, unequivocally, yes… if other civilizations follow technological trajectories similar to those on Earth. Bear in mind that we’ve only been a space-faring species for under 70 years, less than the lifetime of the average American. My grandfather was born in 1897, nearly seven years before the Wright Brothers launched their first successful flight from atop a sand dune in North Carolina. Yet, he lived to see Neil Armstrong walk on the moon in 1969 and later the launch of the Space Shuttle. Now, some 50 years after the first moonwalk, there is already a plan to send a probe to our nearest stellar neighbor, Alpha Centauri, four light years from earth. Conceived by billionaire Russian physicist Yuri Millner, “Project Starshot” quickly attracted the support of Stephen Hawking, Mark Zuckerburg, Avi Loeb, and others. The plan is to use a massive laser to propel a small sensor package equipped with a light sail to 1/5 the speed of light. Depending on how long it takes for the probe to reach its maximum velocity, 20-30 years will elapse here on Earth before the probe arrives at its destination. However, due to the time dilation effects of relativity, there would be a reduction in the actual travel time experienced by an interstellar craft and anyone aboard it. More to the point, if a single wealthy individual can send a probe to another star system, what doubt is there that a far older and more advanced alien civilization could send probes across interstellar space? Note that there is no requirement for superluminal travel. In fact, a space-faring civilization expanding through the Milky Way at 20% of the speed of light could theoretically colonize the entire galaxy in as little as 500,000 years, a tiny fraction of the galaxy’s lifetime. It is also conceivable that more advanced civilizations have achieved faster than light travel by exploiting wormholes, “interdimensional travel,” or by some other means we have not yet conceived. Other civilizations may also have developed the ability to extend biological lifetimes indefinitely. If nothing else, it is easy to imagine uncrewed but highly intelligent probes, perhaps even self-replicating probes, gradually spreading throughout the galaxy. If this seems fanciful, recall that there already are functioning probes operating in interstellar space. CONTINUE READING: thedebrief.org/the-paradox-of-fermis-paradox/
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Post by auntym on Dec 17, 2022 13:52:11 GMT -6
www.coasttocoastam.com/article/paper-argues-humans-not-interesting-enough-to-warrant-attention-from-aliens/Paper Argues Humans Not Interesting Enough to Warrant Attention from Aliens
December 16, 2022 By Tim Binnall / www.coasttocoastam.com/pages/tim-binnall/An intriguing new paper exploring the question of why Earth has not been visited by aliens puts forward the somewhat dispiriting theory that humans may simply be too primitive to warrant attention from technologically advanced ETs. The thought-provoking concept, put forward by astrophysicist Amri Wandel, originated as an attempt an answering the famed Fermi Paradox, which observes that the universe is teeming with life, yet our planet has never been contacted by extraterrestrials. While many answers to this conundrum from scientists revolve around the possibility that life in space may actually be fairly rare, Wandel offers a different scenario wherein life may be so abundant that aliens looking to make contact with advanced civilizations may not find us all that interesting yet. Arguing that despite being advanced beyond our wildest imagination, a hypothetical alien civilization would still have limited resources to use in their search for intelligent life in space, Wandel postulates that they "would choose planets with special properties as targets to their probes." Specifically, he suggests that the ETs might look for worlds which display a technosignature, such as radio transmissions, which would set them apart from planets that only show signs of life, since that encompasses all manner of possible critters that cannot communicate with them. " Presuming biological life is common," he writes, "Earth's biosignature would not be outstanding" to aliens observing the planet from a vast distance away. Although our planet has developed something of a technosignature since radio broadcasting began nearly a century ago, Wandel notes that the waves emanating from our planet have only reached approximately 100 light years into space which considerably limits the number of potential alien civilizations which could have noticed that. Additionally, to a space-faring species of advanced beings, radio waves may not be particularly enticing to an alien race that could have discovered them thousands of years ago. While humanity might not qualify as intelligent life in the eyes of the ETs, there's always hope that our radio signals will eventually reach a civilization out there that is curious enough come and find us. www.coasttocoastam.com/article/paper-argues-humans-not-interesting-enough-to-warrant-attention-from-aliens/
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Post by jcurio on Dec 18, 2022 18:37:19 GMT -6
While humanity might not qualify as intelligent life in the eyes of the ETs, there's always hope that our radio signals will eventually reach a civilization out there that is curious enough come and find us.
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Why use the word “hope”?
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Post by jcurio on Dec 18, 2022 18:41:34 GMT -6
Obviously, “they” are already here. Everything, everything, has a history of using what is beneath them. Consciously; or not
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