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Swedish Scientist Suggests That There Is Only One Earth (blastingnews.com)
MarkWhittington writes: The conventional wisdom has been among scientists is that a myriad of Earth-like planets exist in the universe, some of which have to be the abode of life, even intelligent life. However, Astrophysicist Erik Zackrisson from Uppsala University in Sweden has run a computer simulation of the universe, incorporating what we know about exoplanets thanks to the Kepler Space Telescope, the laws of physics, and the state of the early universe. The computer simulation came up with exactly one Earth, which is to say the one we live on. Every other planet in the universe does not have the conditions necessary to sustain life. Indeed, strictly speaking, Earth itself should not exist, according to the computer model, according to the story in Discover Magazine.
I read it in a book
If his model says that Earth should not exist, then there's something wrong with his model.
Also, considering how life thrives even in hostile environments here on Earth, it's simply a mathematical impossibility that there are no other planets in the universe capable of supporting some kind of life.
If telephones are outlawed, then only outlaws will have telephones.
I refute it thus. #theoldlinesarethebest
Computer modeler cranks out computer model that predicts that things we know to be true are not true, and then asserts the universe is wrong....
If it didn't, would we all be dead?
`Oh dear,' says God, `I hadn't thought of that,' and promptly disappears in a puff of logic.
If earth is such an uncommon place to live in, then maybe we, in fact, are the extremophiles
The huge problem here is that his data is based on what we know about exoplanets so far. Of course his model will show most of the planets are much larger than earth. Those are the ones we're able to find so far.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
This headline-ready conclusion seems like a bit of a stretch. From TFA:
The model creates exoplanets based only on the ones we have discovered, which is an extremely small sample size that probably doesn’t provide a representative cross-section of all of the planets in existence.
Seems like we don't have nearly enough data to say there's only one Earth-like planet.
...according to the computer model.
Says something about the model, then, doesn't it?
If this is accurate this is good news. One of the standard explanations for the Fermi Paradox is that Earth-like planets are very rare https://en.wikipedia.org/wiki/Rare_Earth_hypothesis. You may ask why this is good news? The reason is that something is making civilizations rare. We don't see any signs of major civilizations, either in terms of visits, radio waves, or most importantly, megastructures and large-scale engineering projects. At this point, we've looked at 100,000 nearby galaxies and essentially none of them show signs of a highly advanced civilization in terms of energy use http://www.universetoday.com/119931/100000-galaxies-and-no-obvious-signs-of-life/.
The standard explanation for this is that there is some "Great Filter" which is making civlizations rare https://en.wikipedia.org/wiki/Great_Filter. If this is something in our past (e.g. habitable planets are rare, it is tough for life to evolve, it is hard to get those last few steps to necessary levels of intelligence, etc.) then we don't need to worry. But if it is something in our future, something that civilizations do to wipe themselves(e.g. nuclear war, bad nanotech) out then we're in trouble. We need to figure this out soon, since if there is a future Filter then it likely occurs very close to our current tech level.
Every piece of evidence for early filters should make us breathe more easily since it makes late filters less necessary. Unfortunately in the last few years, almost all new evidence has been in the other direction: we've found lots of planets and it looks like even small, rocky planets are common. So this is a refreshing piece of news. However, I'm very skeptical of it. First, it seems to go against other similar studies suggesting that as many as 1/3rd of stars may have an Earth-like planet (see e.g. here http://www.universetoday.com/119931/100000-galaxies-and-no-obvious-signs-of-life/) and they appear in order to be getting this result in part to be using an extremely narrow notion of what a habitable planet would look like.
There may be life, Jim, but not as we know it.
Sensor scans are inconclusive. I recommend an away team investigate more closely.
If your model doesn't account for reality, is your model deficient? I'd say yes.
Many things are improbable, but in a vast universe, improbable becomes fairly likely.
So, if he can't account for the Earth we have, the estimation of other ones like it is pretty useless.
Lost at C:>. Found at C.
The Fermi paradox is easily solved by noticing that the universe is very big, and very empty, and that the limits of technology do not allow sufficiently easy travel.
When one refers to a "1 in a million chance" they are not implying that they actually tried something 1 million times and it only worked once. They are implying that *if* they would have tried something 1 million times it would have only worked once. So if you win the lottery jackpot, your winning ticket was still "1 in 300 million" regardless of how many other tickets you bought or how many exist.
The title of the article is "Earth may be a 1-in-700 quintillion kind of place", but the article cites the 700-quintillion number as the total number of planets, and then goes on to say that according to the scientist's calculations, the earth should probably not exist (i.e. the odds of an earth like planet are even lower than 1 in 700-quintillion). So what are the odds that earth should exist? Who knows, it's not even mentioned.
This would be like if I reported on some guy winning the powerball and said "This guy bought 100 lottery tickets and one of the tickets won the jackpot. That was an amazingly improbable event that happened, making the ticket a "1 in a hundred kind of ticket.""
I have no idea if the statistical analysis done by this scientists is good or bad. But all I ask is that it is presented in a way that is coherent.
This does not work. We can see very far. That explanation would only work if the sole problem was a lack of visitors to our star system. But as I discussed in my comment, we don't see any radio waves nor do we see any signs of megastructures or other large-scale use of the large amount of available energy. The universe looks completely natural. Incidentally, it is also worth noting that the distance explanation doesn't seem to work very well either.
The galaxy for example is about 100,000 light years across. That means that if one is going only 1 percent of light speed (which does seem doable given what we know of the laws of physics) one gets from one end of a galaxy to another in about 10 million years, and can colonize most of a galaxy in about 200 million years, which is not incredibly long in comparison to the amount of time life on Earth has been around.
So the long-distance explanation doesn't seem to work very well for explaining a lack of visitors, and doesn't go anywhere to explaining the complete lack of other signs of civilizations which are the much more puzzling thing.
He is correct, Earth does not exist.
Or did you forget it was destroyed by the Vogons ? The supposed highway is just a bit delayed, that's why you don't see it. Takes some time in cosmological units.
But as I discussed in my comment, we don't see any radio waves
Which means very little. Go to the nearest star and aim a large receiving dish at Earth. You won't hear a thing, unless by accident someone on Earth points a focused transmitter at you, at the exact right time.
That means that if one is going only 1 percent of light speed (which does seem doable given what we know of the laws of physics)
At that speed it may take several thousand years to reach another habitable planet. With a million things that could wrong, I can see people voting against the idea of embarking on such a crazy adventure. And even assuming a bunch of people make it to another planet, they have to survive there, and rebuild another civilization capable of doing it again. If the failure rate is too high, the spread will stop.
Anthropic Principle
We tend not to observe universes in which life is impossible.
-Dave
Let's say there's an alien civilization out there with technological progress. First of all, they would have to be advanced enough to use radio waves. An "Earth at the 1600's" would be invisible to us. However, they would also need to not have progressed past blanket radio wave bursts. As we communicate more and more via wires or direct satellite communications, less of our chatter will be audible to space. Let's say that the alien race proceeds about how we do. They would have about a 300 span (being generous) from "first visible via radio waves" to "went silent."
This 300 year span would need to occur while we were able to look for them. If the last of their radio waves passed us in the 1200's, we wouldn't have detected them. It would also have to occur in a portion of the sky we were looking at. They would also need to be close enough for the radio wave strength to be detectable. If they are five galaxies over, we'd be hard pressed to detect the signal even if they aimed it right for us.
Let's say we were lucky enough to be looking in the right spot at the right time and they were the right distance away. Would we recognize a signal? The signal would be in an alien language, using an alien encoding algorithm, perhaps compressed using an alien compression routine. It wouldn't be a video in English encoded using MP4 and zipped using gzip. Given all the alien-ness of the signal, there's a strong possibility that we could discount it as mere noise and move on.
Just because we haven't detected a signal (and recognized it as one) doesn't mean intelligent alien life doesn't exist out there somewhere.
As far as megastructures go, space is huge (insert Hitchhiker's Guide quote here) and we're just now approaching being able to detect Earth-sized objects. Why does the lack of "We found a super-Jupiter sized thing that's not a planet" announcements mean that there can't possibly be five hundred alien mega-structures the size of our moon in the Andromeda galaxy.
My sci-fi novel, Ghost Thief, is now available from Amazon.com.
There are millions of focussed transmitters on earth, though most of them point toward a handful of spots in the equatorial plane, they are above and below the equator on earth and east or west of the satellites so the trasmissions should fan out.
They're also mainly on land not on the oceans, so perhaps it would be possible to detect patterns of higher and lower transmissions as the earth spins even if it's not possible to make sense of any specific transmission
Nullius in verba
How many have truly died out, though?
Rome is a great example -- you can argue that the Western Empire fell in 476, or you could argue that by 476 Roman culture had been so influential for so long that the end of an official government empire wasn't really the end of the civilization -- people didn't suddenly drop every last bit of Roman cultural traits. Latin was still spoken, Roman buildings, cities and roads were still used and so on.
To this day, we call one of senior legislative bodies the Senate in a building that borrows a lot of architectural elements from Rome.
Did Roman civilization end, or did it just evolve into what we now refer to as Western Civilization?
All this speculation is pretty silly IMO, because you're trying to draw conclusions about possible civilizations far more advanced than ours, using a ridiculously small and limited amount of data from a civilization that hasn't even really left its own planet yet, except for a few primitive robotic probes within its system and one manned mission to its nearby moon for rock collecting. We haven't even visited our nearest neighboring system.
We have no idea how many habitable planets are out there, because we can't even detect them. All the exoplanets we've seen have been big and very close to their stars, because that's what our limited technology allows us to see. We would not be able to see an Earth in orbit around Alpha Centauri, much less a much farther star. 20 years ago, we didn't even know definitively about any exoplanets at all, but when we developed the capability of seeing "hot Jupiters" suddenly we started seeing hundreds of them. Most likely, there's an enormous number of Earth-sized planets out there, we just can't see them yet.
The search for radio waves is dumb. We don't even use high-powered radio waves any more, we only did for a very brief time, and radio is very hard to detect over large distances due to the Inverse Square Law. The whole SETI search seems to be based on the silly idea that ETs are out there, working their asses off to build the biggest radio transmitters they possibly can and then devoting all their energy to powering them, just so they can point these transmitters at us to send us a signal. We don't do that, so why do we assume anyone else is going to?
The megastructure thing is pretty silly too: a Dyson sphere (or better yet, a Dyson swarm which is much more realistic) wouldn't be easily detectable by us because it'd be blocking all the star's light, and would only be detectable by IR radiation. Are we even actively looking for such things? And would we be able to detect them?
Honestly, even if there were a Star Trek TNG-level civilization out there in the Delta Quadrant, we wouldn't be able to see it. It's too far away, and we wouldn't be able to detect their technology. There's a lack of signs of civilizations because we do not have the capability of seeing them, and we haven't put that much effort into looking, and certainly not into leaving our star system to check out neighboring systems. It's a lot like living on an island and concluding there's no other civilization out there because you haven't seen any come visit you, when you haven't even bothered building a boat and looking for yourself.
Drake's equation is the product of a lot of different probabilities - galactic evolution, stellar evolution, planetary evolution, planetary habitat evolution, the origins of life, the sustainability of life to survive to become something we can study. the evolution of species, the evolution of intelligence, the evolution of a stable society, and so on. Each of these factors has large error bars according to the experts in every field. The best average, which is probably meaningless, has it that there are probably hundreds of civilisations in the Milky way, though probably none with contactable distance in our lifetime. However, the only evidence we really have, from our own planet, suggests that life got going so early that the planet's surface was still part molten when it did it. This suggests that, given roughly the right conditions, life may come into being pretty quickly. It then took most of time to get to a state where complexity took off, which suggests (on a population of one, admittedly) that the initial evolution of life is less of a barrier than something like evolving a decent cell wall. It makes sense to look for life on Mars and Europa, though most people do not actually expect to find it.
Yet, we are told there is this one scientist who has a computer model that says the number of possible earths, modelling all these various disciplines, is exactly one, and with no mention of error bars (and therefore God, and hence Baby Jesus and the Virgin Mary, checkmate atheists). I suspect journalism rather than science is happening here. However, if it is the scientist, and he really claims one person can outsmart everyone else in all these fields, then he really needs to show his working. Science is not a democracy, and one person can beat the majority. But it is pretty damn rare. And most of us do not claim to know what most of the mass of the Universe is just yet, let alone how many lifeforms it has made.
I am not saying God does not exist. Proper science has the humility to recognise the limits of what it can measure and understand. But this is just someone standing on science and using it as their pulpit.
Not widely discussed, but is a logical answer to the Fermi Paradox.
http://brighterbrains.org/arti...
TL;DR: We vanish in a puff of logic.
..don't panic
Actually, according to Dr. Drake, the inventor of the Drake Equation, founder of SETI, Earth is becoming less visible all the time. The satellites you talk about aren't pointed out into space, they are pointed towards Earth. We have also switched from analog to digital transmissions, so essentially everything we're transmitting at this point is indistinguishable from noise. Broadcasting large amounts of energy into the universe in analog is not something that we can expect other civilizations to do for a very long time, if our own civilization is any guide. Not only that, but the Sun also produces a fair amount of radio-frequency radiation, so there's a pretty high noise floor. Even when we're trying to talk to Mars, the SNR is miserable.
The odds against detecting extraterrestrial transmissions, or extraterrestrials detecting us, are so insurmountably vast as to defy description. I think that Dr. Drake should accept the logical conclusions of his statements and end the SETI project. We have met the Great Filter and he is us.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
The "half colorblind world" is not an apt analogy for faith in God.
A defining feature of faith is the untestability of its object. The inability to convincingly communicate it is not. Nor is the unawareness of a provably extant characteristic.
In half colorblind world, you could perform any number of tests to show that color-sighted people can distinguish patterns or shapes of equal luminosity but different hue.
Likewise, colorblind scientists would be able to investigate both the visible spectrum and the effect various wavelengths had on the weird cone structures that only existed in the eyes of color-sighted people.
That analogy might work better for antivaxxers or climate deniers. "We know this is something you can't poke with a stick, but you'll have to take it on 'faith' that the overwhelming conclusion from hundreds of studies is that some people can discern different parts of the visible spectrum."
Nothing posted to