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I would be surprised that any scientist would say this. How can they say tisd at this point?The problem with this is that it based on the exo-planets alreday discovered, but something as small as earth is just not likely to be found.Still, there are actually good reasons for this - just not his reasons.
Theer are alot of things in this solar sstem even smaller than Earth, so it would be hard to say something that siz could not exist. There is also the argument that something with an oxygen atmosphere is just not natural.
From the Article:His research indicates that, from a purely statistical standpoint, Earth perhaps shouldn’t existYet it does. That would suggest to me that perhaps the statistical model is wrong. GIGO, as they say.A kinder way to say it: You've shown your findings far too early in the development of your statistical model.
Every so often I feel that I have to remind people like Green that there is no actual evidence of life anywhere in the universe other than on the earth.
This sounds just like the kind of crap the "intelligent design" people used to purvey. And I am thinking it is probably just as "scientific" If you have a thousand assumptions, which would be a small number to support a conclusion like this, and each of them has a 90% probability of being correct, your chance of being right is effectively zero.
Every so often I feel that I have to remind people like Green that there is no actual evidence of life anywhere in the universe other than on the earth.Absence of evidence, evidence of absence... but at some point the smart money does begin to move.
Cats would quickly overrun any place we migrated to.
That creation of the earth and life on it from stray atoms by accident HAS TO HAVE other earths out there, right. Now, go look harder. Faith in a God doing it is way too dangerous an idea. You know, one of those stray ideas that came from an accident.
So basically its like a climate model, but of the universe. I am sure it is 100 percent reliable! We should ask it what Althouse is going to post next!
Another thing to keep in mind is they're talking strictly about the "observable universe" with all this. The entire Universe could be several orders of magnitude larger. So you'd have to add a few more zeros. At any rate, when talking about numbers that large even if Earth is an outlier amongst outliers amongst outliers, it's still a virtual certainty that there would still be some number of Earth analogues.
There are known knowns and unknown knowns, known unknowns, and unknown unknowns." But hey! I have a supercomputer!
An exercise in futility. The distances are just too enormous.
If you were to ask a thousand Americans if there is life on other planets, either in our solar system or elsewhere in the universe, most of them would probably say 'yes'. This belief comes from a hundred years or so of science fiction in pop culture, not from scientific observation. A cynic (or realist) would note that we have spent a great deal of money on interpalnetary probes and experiments designed to detect life on other worlds (Venus and Mars, for example), and we have not found life on other worlds.On the other hand, the building blocks of life -- organic compounds and water in the form of ice -- seem to be ubiquitous throughout the universe. Probably most stars had these in abundance when they formed planetary systems. So where is everybody?One theory I've heard is that life on earth required deep time to develop. It may be that other planets and planetary systems are not stable enough for enough time to develop life. In their early histories, Venus got too hot for life to develop, and Mars got too cold and lost its atmosphere and its protective magnetic field.
Extrapolating wildly from a small sample size is a lousy way to draw conclusions about unlikely events.
Since the Earth isn't optimal for life, maybe that implies there's a higher likelihood of illegal aliens in outer space than if there were more planets like the Earth.
He must be a climate scientist.
And how far is it from a Nulcleus to an electron in an atom? And how far is it from Heavens to the edge of the material Universe...oops, that is spirit realm talk and nobody counts spirit realms as being real.And how long is Eternity, anyway?
"And how long is Eternity, anyway?"A long time, especially near the end.
Hagar said...An exercise in futility. The distances are just too enormous.I am surprised that people still think that we are going to send people to Mars in the mid 2030's. People suffer significant and permanent bone loss when they are exposed to microgravity for a long period of time. Prolonged exposure to radiation is a problem as well.The silliest thing I've seen is an artists conception of a 'marsnaut', wearing a space suit, standing next to some kind of inflatable dome on the surface of Mars. Really? The one time in 21 months that you can actually protect yourself from radiation by surrounding yourself with mass, and you are going to camp out in a pup tent?
I hope, for his sake, this guy's already tenured.
I've mentioned this before and I'll say it again.I was once told that intelligent design theory is wrong because it can't make predictions. I pointed out that it makes correct predictions unlike evolutionary theory. Such as, every part of our body has a use. Many years ago, during the scopes monkey trial, we had approximately 100 parts of our body that scientists believed were useless. Now I believe that number is 2. Because the evolutionists prediction is, we would evolve and would no longer have a use for certain parts.The same is true for "life out there". If you believe in evolution and the big bang explanation, then there should be lots more life out there. That would be your scientific prediction based off of the evidence. You would say, it just makes sense. The more time and space and planets, the higher the chance of more life. If Earth is a one in a million shot, then for every million planets, give or take, you've got another earth like planet. That's your prediction. So, go spend billions of dollars and spend hundreds of thousands of man hours trying to prove it.If you believe we are intelligently designed, your prediction would be different. You could look at the facts and say, you know, this Earth planet was created so uniquely, positioned so perfectly, with conditions so tuned, that it really would never happen by chance. And therefore, we won't find anymore life out there unless it too is designed in a similar way.I prefer the design argument because it saves us a lot of time and money.
If the writer of that article genuinely believes that this scientific claim is revelatory, beautiful, and terrifying, then I invite him to take a good, long, hard look at my hairy asshole.
Terry said...Every so often I feel that I have to remind people like Green that there is no actual evidence of life anywhere in the universe other than on the earth.True. It is also true that, of the planets we've examined closely enough to determine if they've ever held life, 100% have, and still do.Of the solar systems that we've examined closely enough to determine if they hold intelligent life, 100% do.If there is life out there, and it its development has advanced in parallel with ours, we would have zero chance of knowing it unless it was within 100 light years of us, and little chance even if it was only 20 light years away.We haven't even scratched the surface of looking.
The "scientific consensus" on global warming has done much to undermine the authority of all the sciences of mindless speculation.
Quantum estimates of the cosmological constant are off by a factor of 10^120, which has 120 zeros. This is known as the worst theoretical prediction in the history of physics. Worse than climate science.
It is true that absence of evidence is not the same as evidence of absence.I would say there is an absence of evidence of any extra-terrestrial life. That leads to the conclusion that the earth (and mankind) is a very, very, very special place, given the gazillion planets/stars in the Universe.There has been a cultural push (Star Trek, Star Wars, Close Encounters, X Files) to get comfortable with the idea that something else exists somewhere out there, but we haven't found it and may never find it. That's the breaks.Not to politicize this topic, but the cultural/scientific Left argues that we are not special, but merely a product of happenstance, and, if so, that a similar product should emerge, also by happenstance, elsewhere. They hate it when the facts don't support this meme, but rather tend to support the hypothesis of Special Creation. It inches them, factually, towards God, where they don't want to be.
Eric wrote:"The same is true for "life out there". If you believe in evolution and the big bang explanation, then there should be lots more life out there."The unspoken assumption in all of modern science is that there is nothing unique about our observation point. We are at an unremarkable time in the history of the universe, at an unremarkable location, and are unremarkable in composition. We do not have a privileged POV.If there is no other life in the universe, that unspoken assumption may have to be revisited.Or is it an unspoken assumption? I've never heard that it was a name.
The global alarmists keep telling us that if we deviate only a couple of degrees one way or the other, it will be the end of life on earth.The conditions necessary for that slim window of opportunity are rare even in our own solar system. If earth were a few thousand miles further out, it would drastically change things here.The fact that the earth happened to be so lucky so as to be just the right distance away from the sun, which radiated just the right kind and intensity of light and heat, and the temperature of the planet was just right and it had just the right kind of elements in the right proportions so as to be able to form oxygen and water, shows that we are either extra-ordinarily lucky, lucky beyond imagination, or there is something other than accidental luck going on here.The question is why some people are so threatened by the thought that perhaps it is not all dumb luck that the earth exists as it does, that life is not the result of the haphazard collision of molecules and electro-magnetic pulses, that humanity is not the product of spontaneous animation of matter in a universe of chance and arbitrary randomness. Why is there this anti-scientific resistance to considering the idea that maybe, just maybe, there is some rational intentionality from some greater transcendent reality beyond the known universe behind this? You would think that people would be happy to know that their existence is not all accidental and meaningless, but that they were and are desired and willed to be.
The key is:"Zackrisson’s model combined information about known exoplanets with our understanding of the early universe and the laws of physics to recreate the past 13.8 billion years."Too much attention is being paid to the exoplanet comment, not nearly enough to the Big Bang, general relativity, and quantum mechanics. In other words, the best-attested hard science we have. We actually do know how information processing works as a matter of physics (otherwise none of us would have an "internet" to debate on). We know it takes carbon or silicon. We know hw carbon and silicon are formed. And millions of other things that have causal relationships that we know.In other words, this isn't like a climate science model, which tries to predict a specific future state of a real complex non-linear dynamical system that it can't possibly model accurately and whose initial conditions are unknown. This is taking the Big Bang, general relativity, and quantum mechanics, checking the model against the facts of the known exoplanets, and saying earth, specifically, is extremely unlikely to arise from these conditions. "Unlikely" doesn't mean "won't" or "didn't," and earth's existence doesn't change the probability (cf. the Monty Hall problem, where Monty showing you an empty door after you've chosen a door doesn't magically raise your probability of having chosen the right door from 1/3, so you should switch).Why it's so hard for people to accept what is a rather obvious statistical fact is a curious thing. Why are people so invested in the loopy idea there's nothing special about earth or humanity? What's with the thinly disguised self-loathing?
So, the answer to the Fermi Paradox: "Where is everybody?"is: "Nobody's there."
Terry said...Or is it an unspoken assumption?Not unspoken at all. I'm pretty sure it is covered in A Brief History of Time, and probably most other popular descriptions of the origins of the universe.The version you state is also entirely rejected. What the excepted version includes is that, since we are here to observe it, we must be in a location in space and time where life can exist, and where it could have formed or migrated to. If we are unique in the universe then clearly we are in a very special place, and it is reasonable to ask why such a special place exists. But we are a very long way from determining if our place in the universe is unique.
how long is Eternity?That is a wholly irrational nonsensical question. Eternity transcends temporal, linear time. Eternity is simultaneously singularity and totality. In eternity, all moments exist in one and one moment exists in perpetuity.
Those government grants won't spend themselves, you know.
Ignorance is Bliss said..."We haven't even scratched the surface of looking."We've done the easy bits. Absent technological improvements, looking will get more expensive. I am agnostic on the topic. The latest idea seems to be that life may be found on Mars, in places where water may remain in its liquid form or change phase from solid to liquid and back again. Maybe they will find something we recognize as life. Another idea is that life may be found on the moons of gas giants. But I want to emphasize that the universe we live in is not the universe of science fiction. Some very bright, well-credentialed people (like Roger Launius) don't believe that human beings will get past the orbit of Mars, at least not as human beings. Absent something like a warp drive (and warp drives are fiction), the distances are too vast and the space environment is too hostile. People are crappy payloads. They need to be maintained with food, water, and living space within a narrow range of temperatures. They evolved on the Earth's surface. They are easy to kill. They age. They go mad. They can't be miniaturized, they don't scale well.
Ignorance is Bliss said..."If we are unique in the universe then clearly we are in a very special place, and it is reasonable to ask why such a special place exists."Maybe we are talking about different things, Ignorance is Bliss. I am talking about the principle that says that if we find a white dwarf star just 15 light years from the Earth, there must be an awful lot of white dwarfs in the universe, even if we haven't detected them yet.
Mark @ 11:04 said the secret word, the duck came down and he won the secret prize.Now how big is the Universe of 700 quintillion planet accidents again.
Little too soon for a very speculative piece like this to go into the mainstream media. Needs a lot more work, and maybe more data.
The axioms and models will continue to degrade as our society society leaves the scientific domain in order to establish a replacement orthodoxy.That said, resumption of abortion rites and cannibalistic trials under the traditional pro-choice religion are first-order causes of catastrophic anthropogenic global waning.
"""A new study suggests that there are around 700 quintillion..." When I was got this far I thought it was the anticipated US debt after two terms of Bernie Sanders.
The headline on the article is wrong, of course. The study does not suggest that there is "only one like Earth". The study suggests that there are no planets like Earth in the Universe. Caveat lector.
Paul Snively said...This is taking the Big Bang, general relativity, and quantum mechanics, checking the model against the facts of the known exoplanets, and saying earth, specifically, is extremely unlikely to arise from these conditions.The typical way to model something like this is to run the model many times, and see how often it produces results like what we observe. If it typically produces result like what we see, then the model is robust, and we can use it to make statements about how likely the things we observe, such as different types of planets, actually are. If it rarely matches observation, then it is not robust, and we should not rely on predictions it makes.So how many times did they run this model? And how many times did it predict earth-like planets? For them to say that the earth only happens once out of 700 quintillian planets, they would have to simulate the formation of 700 quintillian planets, in ~100 quintillian solar systems, and have just one produce an earth. Obviously they don't have time for that. So I suspect what happened was they ran the model many times, simulated the formation of a lot of solar systems, an got no earths at all.If so, this would mean that their model consistently failed to match the observable universe. Reporting such a result would likely not earn them any headlines.
Blogger Fred Drinkwater said...'The headline on the article is wrong, of course. The study does not suggest that there is "only one like Earth". The study suggests that there are no planets like Earth in the Universe. Caveat lector.'Are you saying Earth isn't a planet? Did we get downgraded like Pluto?
"I prefer the design argument because it saves us a lot of time and money"But it does nothing to help us understand the universe based on the available evidence. Whether that's worth time and money is a separate question. Many of us who believe in God also want some insight as to how he created the Universe, and believe that by studying the physical evidence He created, we can gain insight into how it all began. The "Design" theory just seems like a cop out for the incurious.
Yeah. We will teach God a lesson. We will use our super computers. Our Super computers v. The Supercomputer Himself.
People are crappy payloads. They need to be maintained with food, water, and living space within a narrow range of temperatures.... they don't scale well.Boy ain't that the truth. When my kids scaled up from 8-yo size to mid-teen size they became moody and smelly.
traditionalguy said...That creation of the earth and life on it from stray atoms by accident HAS TO HAVE other earths out there, right. Now, go look harder.Not really. There is a very real possibility that we are an anomaly. However if I were a betting man I'd say that the odds are with life on other planets. But like Hagar said. The point is mute. We will never know. The physics precludes us from knowing.
Obviously, the Earth is unique. Every planet is unique. I could also say that there are 700 quintillion planets, but there's only one exactly like Mars, namely Mars.There are 7 billion people on earth, but only one who is exactly like you, namely you.The issue isn't whether there are other planets *exactly* like Earth. The question is whether there are planets with life. None of them will be *exactly* like Earth.Carl Sagan, in his "Cosmos" TV series, speculated on what some intelligent aliens might be like. Neither alien race was *exactly* human, and neither planet was *exactly* like Earth.First, here's a race of intelligent plant-like beings on a planet sixth from their sun:Star: spectral class F.Planet: sixth.Biology: C, N, O, H, S, Se, Cl, Br, H2O, S8.Genetic code: Polyaromatic sulfonyl halides (not DNA).Mobile photochemosynthetic autotrophs in weakly reducing atmosphere.Polytaxic, monochromatic.Culture: Global, nongregarious, polyspecific (2 genera, 41 species). Arithmetic poetry.And here's an ultra-advanced race of exotic electric aliens:Interstellar civilization, no planetary communities, utilizes 1504 supergiants, OV, BV, AV stars and pulsars.Local Group polylogue.Civilization age: 193 million Earth years.Biology: C, H, O, Be, Fe, Ge, He.Metal-chelated organic semiconductors, types various.Cryogenic superconducting electrovores with neutron crystal dense packing and modular starminers; polytaxic.So if Sagan was right, "exactly" doesn't enter into it.
There really is no way to know whether there's extra-terrestrial life until we discover it somewhere. And if we never discover it, we will never know.
I suspect that a key ingredient for the rapid development of life is the Moon. It not only stabilizes Earth's axis but creates tides.The Earth-Luna system is better described as a double planet.How many small, double planets, within the "habitability zone" of a sufficiently metallic (third or fourth generation), relatively quiet sun have been discovered?None. So far.
It would be hilarious if we actually were contacted by aliens, and they were exactly like the 1950s-1960s aliens we now know to be entirely hokey.-Humanoid, but with antenna, odd colored skin, and facial features that look like they are wearing rubber prosthetics from STOS.-They would give themselves a name like 'Zoraxians.'-They would have individual names like 'Klaxor.' Love them X's.-They would have exotic sex lives and reproduction biology, Say, three sexes and their children would be conceived by the three, but birthed by the 'colony mother queen.'-They would have guns like stream lined pistols that made a humming sound and vaporized people, leaving only a rapidly disappearing green glow.-They would be really good at math, and would not understand 'earth humor.'
I was once told that intelligent design theory is wrong because it can't make predictions. I pointed out that it makes correct predictions unlike evolutionary theory. Such as, every part of our body has a use.Actually, evolutionary theory does make that very prediction, or at least that every part of the body has some use, or is related to something that once had a use. Intelligent design only makes an observation. And who is to say that God is not whimsical? And if you don't allow God to be whimsical, but rather tie him down to ordered tracks, how is he any different than the universe itself? Why do you need him? Don't answer that. My IQ is so far below you people that understand ID that I can't even understand the stuff you say.
@TerryOr they could be like the Japanese. Four out of six ain't bad.
OpenID icepilot said...I suspect that a key ingredient for the rapid development of life is the Moon. It not only stabilizes Earth's axis but creates tides.The Earth-Luna system is better described as a double planet.To be life like we have on earth, you need a strong magnetic field and plate tectonics, and a water cycle. Probably something like an oxygen cycle as well (oxygen tends to bind to other atoms). We have deposits of iron on the Earth's surface because it was concentrated by cyanobacteria before the 'oxygen catastrophe' a few billion years ago.You would also need a Jupiter sized planet in the system to clean out the comets, or any developing life might be snuffed out by the occasional collision with gigaton objects.
The Earth came into being from random chances within the framework of the forces of nature. We have no reason to believe that the initial state that lead to the Earth's formation and hence to us are so unique that it happened only once. That might be true but we have no way as of now to know that and we have no reason to doubt that other planets out there somewhere can't be comparable to what we have.
What gives me pause about the Fermi paradox is that there were two huge continents capable of supporting intelligent life that were unknown to all the best minds in China and Europe until relatively late in the game........God could make many varied forms of life throughout the cosmos. Whether or not we exist uniquely neither proves nor disproves God's existence........It's much more fun to speculate about brave new worlds populated by beautiful women with gossamer wings rather than brooding about being alone on this inhospitable planet with all its damned gravity and mortality. Guardians of the Galaxy, Star Wars, Star Trek, et al are a more life enhancing experience to watch than Long Day's Journey Into Night......This isn't necessarily a pro Trump post.
...you need a strong magnetic field and plate tectonics...Why do I need plate tectonics? I'm thinking I'd rather do without, though now I'm not so sure...
Plate tectonics recycles materials which naturally leach out of the atmosphere into minerals.
Blogger William said...What gives me pause about the Fermi paradox is that there were two huge continents capable of supporting intelligent life that were unknown to all the best minds in China and Europe until relatively late in the game...The really odd thing is that agriculture was developed in the new world independent of agriculture in the old world (maize vs grain), and apparently the two staple crops were developed within 2,000 years of one another. The popular idea is that the timing must have had something to do with the end of the ice age, but that's just fitting a correlation to an observed outcome.
"Every so often I feel that I have to remind people like Green that there is no actual evidence of life anywhere in the universe other than on the earth."That's like a microbe in a pond in the back yard stating "there is no actual evidence of life anywhere in the universe other than in" that backyard pond.The microbe hasn't the means to examine more than an infinitesimal bit of the universe, and much of it that it can examine or observe is at quite a remove, mitigating much more than speculation about the infinite based only on glimpses of the infinitesimal.In other words, it is a meaningless comment deriving from utter ignorance of most what exists.
I'm going to have to read this guy's paper, because on the face of it it's farcical. He models the universe and concludes there's only one Earth. Riiiight.
n other words, it is a meaningless comment deriving from utter ignorance of most what exists.Are you saying that there is empirical evidence of life somewhere besides the earth, Robert Cook? If so, please call NASA and let them know. They'll give you a medal or a grant or something.
And here I was thinking there were only 614.25 quintillion planets!!
I'm going to have to read this guy's paper, because on the face of it it's farcical. He models the universe and concludes there's only one Earth. Riiiight.I am willing to bet that the only honest conclusion one could draw from his data alone is that there is no Earth.
Suppose we were contacted by aliens who looked exactly like us except in one thing that made them look ridiculous and impossible to take seriously, like their noses were upside down and they had little manufactured umbrellas strapped to their heads to keep the rain out of their nostrils. That's no less likely than any other scenario. Well, maybe a little less likely.
"Are you saying that there is empirical evidence of life somewhere besides the earth, Robert Cook? If so, please call NASA and let them know. They'll give you a medal or a grant or something."Not in the least. Are you asking rhetorically, or are you really that obsuse?I'm saying the comment is meaningless as regards how likely or unlikely it is that there are other earth-like planets in the universe, or other life in the universe. A microbe in a back-yard pond hasn't the means to examine virtually any of the universe, so a microbe's comment that no evidence existed for life anywhere else in the universe (outside the pond) would be as meaningless and useless as your same remark.
"I am willing to bet that the only honest conclusion one could draw from his data alone is that there is no Earth."I'm sure you're right. You'd think it would give him pause.
The Emperor Ming: "Why not? Pathetic earthlings. Hurling your bodies out into the void, without the slightest inkling of who or what is out here. If you had known anything about the true nature of the universe, anything at all, you would have hidden from it in terror."I, for one, hope Emperor Ming is not telling us the truth.
More science welfare dollars expended.Put it in a text-book and make children memorize it for a test.
"Not in the least. Are you asking rhetorically, or are you really that obsuse?"I am not obsuse, but you seem to think that what I wrote about there being no actual evidence of life other than on the earth was wrong. How? Or are we agreed that is no actual evidence of life other than on the earth?
Terry,Your comment, even if exactly accurate, is meaningless and useless.It can only say something about us, and not about the universe beyond us.
rhhardin said...Quantum estimates of the cosmological constant are off by a factor of 10^120, which has 120 zeros. This is known as the worst theoretical prediction in the history of physics. Worse than climate science.At least those scientists aren't insisting we go back to a medieval lifestyle based on their prediction.
Terry said...Or are we agreed that is no actual evidence of life other than on the earth?Answering for myself, not Robert:We are in agreement on that. Are we also in agreement that, if there was life in most solar systems, no evidence of life on other planets is exactly what we would expect to observe, given our current state of technology?In other words, the fact that our observations result in a lack of evidence does very little to change the odds that there is life out there.
Ignorance is Bliss: So I suspect what happened was they ran the model many times, simulated the formation of a lot of solar systems, an got no earths at all.If so, this would mean that their model consistently failed to match the observable universe. Reporting such a result would likely not earn them any headlines.This misunderstands the nature of statistical modeling based on prior information. If you start with what we know of physics and simulate the formation of millions of solar systems and get no earths, it precisely, and strongly, reinforces the idea that the formation of the earth was statistically unlikely. Don't confuse "statistically unlikely" with "probability 0."Let's put this another way. Buy a brand new deck of playing cards. Open it, take out the deck, and give it a good old-fashioned whiffle shuffle. Do this seven times. Now the deck is in whatever order it is observably in. But that doesn't change the fact that for anyone else following the same procedure, the probability of them getting the same order is 1 over 80,658,175,170,943,878,571,660,636,856,403,766,975,289,505,440,883,277,824,000,000,000,000. I don't know about you, but when the probability of something that happened once happening again is 1 in 80,658,175,170,943,878,571,660,636,856,403,766,975,289,505,440,883,277,824,000,000,000,000, I'm satisfied saying it didn't happen again.
I'm with William; I don't see how life elsewhere or lack of it has any bearing on religion. (Who knows how God might communicate Himself to plants, animals, or life on other planets? One would assume that the way He reveals Himself to us would not be the same as the ways He reveals Himself to other living things.)As to whether or not there is other life out there, I'm agnostic. There seem to be reasonable arguments in both directions, but we don't yet have enough data to make a good determination. It will be interesting to see what we find out in years to come.(I admit that I hope we find life on other worlds just because it would be interesting.)
"If you start with what we know of physics and simulate the formation of millions of solar systems and get no earths, it precisely, and strongly, reinforces the idea that the formation of the earth was statistically unlikely."Or that your simulation is poor.
Robert Cook wrote:"It can only say something about us, and not about the universe beyond us."Well, it says something about the state of human knowledge. No one can ever say anything about the universe without saying something about us:Man doth usurp all space,Stares thee, in rock, bush, river, in the face.Never thine eyes behold a tree;'Tis no sea thou seest in the sea,'Tis but a disguised humanity.To avoid thy fellow, vain thy plan;All that interests a man, is man."-Henry Sutton
Paul Snively said...This misunderstands the nature of statistical modeling based on prior information. If you start with what we know of physics and simulate the formation of millions of solar systems and get no earths, it precisely, and strongly, reinforces the idea that the formation of the earth was statistically unlikely. Don't confuse "statistically unlikely" with "probability 0."Doesn't that assume that what we know of physics is correct, down to many, many decimal places? I'm not just talking about the basic physical constants. I'm talking about the distributions of elements within, and variations in density of, the dust clouds that form solar systems. If the models are incorrect they could favor the creation of non-earth-like planets to a degree that does not match the universe. Yes, they check the model against the observed exoplanets. But that is much too small a sample to validate your model to the degree needed to predict those odds.I'm fine with saying that planets like the earth are highly unlikely. I have a problem with someone stating that the odds are 1 in 700 quintillion. How many runs of your model does it take to show that? If you run your model enough to generate a quintillion planets, and no earths are found, you are still not even close.( The real problem is with the headline, which is not supported by the article, and almost certainly not by the research )
Ignorance is Bliss, I am old enough to have seen dramatic changes in the way we scientifically minded humans thought about life on other planets. It wasn't that long ago, less than a century, that spiral nebulae were not known to be 'island universes' outside of our own galaxy. Marcy & Butler, I know, were very surprised when their search for exoplanets revealed that so many solar systems had close-in, very hot gas giants. It didn't fit the models that were based on the only known example (our solar system). So things change.Mars and Venus were early choices for life because they were the most earth like in composition, size, distance from the sun, etc. Since we knew that life existed on the earth, it made sense that life might exist on planets the most like the earth. Venus turned out to be more like Hell than like earth. Venus has some really odd things about it. One of them is that despite it high temperature, its atmosphere is not very dynamic. The atmosphere on Venus is nearly uniform in temperature, pole to pole and sunny side to shaded side. There is no surface wind worth mentioning.Mars is more promising, but we've had orbiters around the Red Planet and landers on its surface for decades. If there is life on Mars, it always seems to be where we aren't looking, and we are trying to look in the most likely places we can to find it.The right mix of chemistry and dynamism driven by a heat source seems to be the current belief for the requirements for life, on the Earth or elsewhere, but (again) it needs to be said that we have no empirical evidence for life anywhere but on the earth.
coupe said...We's say: "Name five of them."Zhang Wei, Zhang Wei, Zhang Wei, Zhang Wei, and Zhang Wei.
Paul Snively said...This misunderstands the nature of statistical modeling based on prior information.Another thing is: what is detectable life, and when can you detect it?The Earth formed about 5 billion years ago (YA).3.5 billion YA: The first life appeared; took 1.5 billion years.2 BYA: The first cells of the type found in most modern organisms; took 1.5 billion years to evolve from previous type of cell..9 BYA: The first multi-cellar organisms; took .6 BY after their type of cells developed, 2.6 BY after first life..6 BYA: The first creatures with a top and bottom, and front and back, as opposed to being blobs; took .25 BY to develop from blobs..5 BYA: The first attempt at a backbone; 3 billion years after the first life..4 BYA: The first 4 legged animals..3 BYA: First proto-reptiles and amphibians..2 BYA: Dinosaurs and warm-blooded animals; > 3 billion years after the first life..007 BYA: Human and chimp common ancestor.0.000000121 BYA: First radio transmission by humans.
Have we established yet whether there is intelligent life on Earth? Maybe we could, you know, monitor TV signals or something, watch political debates....
Everybody knows that the galaxy is studded with M Class planets. Yeesh!
I wonder why we care.When I was growing up, reading science fiction, we thought extraterrestrial life might be just an orbit away: Mars, the desert planet, with canals built by its ancient engineers who were trying to compensate for the disappearance of water (Heinlein had a novel in which the Terran colonizers of Mars traveled on the iced-over Martian canals on jet-powered skates); Venus, the watery planet, mysterious because the surface couldn't be seen through the cloud cover, but with exotic maritime creatures to be seen once we got to the surface, and opportunities for new maritime adventures by the Terran colonists.But now we've relunctantly accepted that there are no inhabited planets (at least none inhabited by creatures we'd perceive as "people") within our solar system, so we're talking about how many inhabited planets there might be in the Universe -- a Universe of gazillions of galaxies each with gazillions of stars. Even if there are billions of inhabited planets, if the nearest one is 1,000 light years away, we'll never get to them, or they to us, and even the possibility of communication seems remote ("Hi, this is Earth calling. Who are you?" Two thousand years pass. "Earth, please repeat message; you're breaking up."). Yes, some people are invested in the notion that it's important whether or not human beings are unique in the Universe, but there are probably as many folks rooting for life "out there" as there are rooting against it.C.S. Lewis's Peralandra uses the mysterious Venus as a venue for a retelling of the Christian story of The Fall.
Ignorance is Bliss: Doesn't that assume that what we know of physics is correct, down to many, many decimal places?Perhaps surprisingly, no, but even if it did, so what? We have extremely accurate measurements of the atomic weights of the elements, and within what error bars. We found the Higgs and have a reasonable estimate of its mass. We have scads and scads of data on the lifecycles of stars and how they emit matter when they go supernova. etc.I'm talking about the distributions of elements within, and variations in density of, the dust clouds that form solar systems.You should confer with Dr. Brian May about that. ;-)If the models are incorrect they could favor the creation of non-earth-like planets to a degree that does not match the universe.But if their models produce both non-exoplanets and exoplanets that are in statistical agreement with the data we have—and nothing I've read contradicts this—then what? So far, I'm reading a lot of "but earth exists, so their model is flawed!" argumentation. I offered the card shuffling example precisely to show that you can't take an extremely improbable event that you observed after it happened as evidence that it must have happened again. At all.I'm fine with saying that planets like the earth are highly unlikely. I have a problem with someone stating that the odds are 1 in 700 quintillion. How many runs of your model does it take to show that? If you run your model enough to generate a quintillion planets, and no earths are found, you are still not even close.That is, again, not how probability works. You don't have to shuffle a deck of cards enough times to see all 80,658,175,170,943,878,571,660,636,856,403,766,975,289,505,440,883,277,824,000,000,000,000 possible permutations to know that the probability of two shuffles of new decks seven times have a 1 in 80,658,175,170,943,878,571,660,636,856,403,766,975,289,505,440,883,277,824,000,000,000,000 chance of being in the same order.
"There are known knowns and unknown knowns, known unknowns, and unknown unknowns." But hey! I have a supercomputer!"I don't think unknown knowns is possible.
"But if their models produce both non-exoplanets and exoplanets that are in statistical agreement with the data we have—"But the data we have, basically the Kepler and doppler-spectroscopy data sets, are horribly limited.
"The unspoken assumption in all of modern science is that there is nothing unique about our observation point. We are at an unremarkable time in the history of the universe, at an unremarkable location, and are unremarkable in composition. We do not have a privileged POV.If there is no other life in the universe, that unspoken assumption may have to be revisited.Or is it an unspoken assumption? I've never heard that it was a name."It is not unspoken. It is explicitly acknowledged and sometimes called the Copernican Principle.
All planets are unique, by definition. There will not be another planet EXACTLY like the Earth.Will there be planets that are "close enough" for humans to live on? Almost certainly. The problem will be getting there, which seems at this moment to be quite difficult. But technology progresses quickly, and the rate is accelerating. Within 100 years (assuming that we don't have some cataclysmic disaster or abrupt shift in our goals) we will have sent at least probes to other star systems, and sent humans there within 100 years after that. Within 500 years, I expect to see several human colonies on other planets.
Terry said: "Venus turned out to be more like Hell than like earth. Venus has some really odd things about it. One of them is that despite it high temperature, its atmosphere is not very dynamic. The atmosphere on Venus is nearly uniform in temperature, pole to pole and sunny side to shaded side. There is no surface wind worth mentioning."No Moon, so no tides, so nothing to stir things up.Terry said: "Mars is more promising, but we've had orbiters around the Red Planet and landers on its surface for decades. If there is life on Mars, it always seems to be where we aren't looking, and we are trying to look in the most likely places we can to find it." Not really. We've landed in spots that looked like SAFE LANDING PLACES, because we don't have a whole lot of control over the landing process. There are a lot of places on Mars that scientists would like to drop a lander, but we haven't tried because it would be embarrassing to lose ANOTHER Mars probe to a landing accident. And remember that a robotic probe can ONLY find what it was DESIGNED to find. We can't re-engineer the onboard sensors to detect something that we didn't expect to find when we designed the probe TEN YEARS AGO. We're likely to find plenty of surprises on Mars, perhaps even ancient life - after we GET THERE.
Given that any life on Mars didn't make it to a very developed state due to the early loss of water, the only practical way of finding evidence for it is with manned exploration. And, likely, a lot of missions or extended visitations Probes are good, and maybe we'll get lucky, but it's naive to think it's a very thorough search.
Why do want to find life on mars, or anywhere else in the solar system? If we find life on mars, it will probably be very basic, maybe not even eukaryotes. I doubt if it will be useful.But if we find that life appeared on mars independently of life on Earth, it means that life will probably be found throughout the universe.
"His research indicates that, from a purely statistical standpoint, Earth perhaps shouldn’t exist."He's not saying that the odds are against it. He's saying that there is no statistical case to be made for the existence of an earth.According to this the chances for an earth and the chances for God are essentially the same.Hmmmm.
AbstractBy 50,000 years ago, it is clear that modern humans were capable of long-distance sea travel as they colonized Australia. However, evidence for advanced maritime skills, and for fishing in particular, is rare before the terminal Pleistocene/early Holocene. Here we report remains of a variety of pelagic and other fish species dating to 42,000 years before the present from Jerimalai shelter in East Timor, as well as the earliest definite evidence for fishhook manufacture in the world. Capturing pelagic fish such as tuna requires high levels of planning and complex maritime technology. The evidence implies that the inhabitants were fishing in the deep sea.From Science Magazine 25 November 2011.
Re: icepilot at 12:54 PMIn fact, the earth-moon system, with the moon almost a quarter the size of the earth, and the sun being about 3rd generation, being seeded most likely from a super nova explosion, allowing the presence of higher minerals on planet earth, are just two of the factors that have been identified as essential to the development of higher forms of life on earth. There are more than 200 other factors, including the presence of plate tectonics that allows recycling of carbon from the atmosphere to under the continental plates. The big black hole at the center of the galaxy has to be the right size and at the right stage also to allow the solar system and earth to have developed as it had.In short, as Fred Hoyle realized, the probability of having all these conditions happen on earth by accident is about the same as chance of a tornado blowing through a junk yard and by accident, producing a Boeing 747. Many physicists accept this but instead of considering the possibility of an intelligent design, they propose the picture of a multiverse. There are an infinite number of universes they say and we just happen to live in a universe that all the conditions came together to allow the development of life and intelligence.
"In short, as Fred Hoyle realized, the probability of having all these conditions happen on earth by accident is about the same as chance of a tornado blowing through a junk yard and by accident, producing a Boeing 747."That would be Fred 'Steady State' Hoyle, right?
Yes. The same one who first used the term "Big Bang Theory" as a form of ridicule.
Every galaxy has a black hole at the center and there's no reason to think ours is unusual, supernovae are everywhere, there's no reason to think plate tectonics is unusual for a rocky planet of sufficient size to keep a hot core, ...
I think that makes us gods.
He was wrong, Jacinto. Spectacularly wrong.
Original Mike, Yes, he was wrong about the Big Bang but he was right about the almost zero chance of all these conditions for the development of life coming together at the same time and at the same place on earth by accident. As for our galaxy's black hole, I once read a Scientific American article analyzing how its properties and present stage of activity contributed to the development of life on earth.
Well, we know the answer to the Big Bang/Steady State question. As to Hoyle being right about the zero chance of all these conditions for the development of life coming together, we currently know little.There is no shame in being wrong, but Hoyle hung on with ridiculous mechanisms to try and explain away the data as it became increasingly obvious that Steady State was wrong. I wouldn't hang my hat on his judgement if I were you. (BTW, I have a soft spot for Fred Hoyle. He wrote one of my favorite science fiction stories; The Black Cloud.)Yes, the Milky Way' s black hole might have contributed to life on Earth. Every galaxy has a central black hole. In fact it's thought that the black hole drives the development of the galaxy so our's is not unique.
Why the lack of the "I'm skeptical" tag?
Whatever. There's not a lot of life in the cosmos. It's mostly emptiness and varying forms of lifeless matter. You were granted the bizarrely improbable opportunity of being a creature who can enjoy beauty and reason, Whether it's a miracle or the fortuitous byproduct of random chance, it doesn't happen very often. Added to that we get to live in millennial America where you don't have to worry about starving to death or dying from a dental abscess. Pretty sweet deal. We won the cosmic lottery.
It's hard to believe that in a universe this big there is only one god.
"It's hard to believe that in a universe this big there is only one god."Yes...exceedingly hard to believe.
It's hard to believe that in a universe this big there is only one godIt's hard to believe there is only one universe.
tim in vermont said...It's hard to believe that in a universe this big there is only one godIt's hard to believe there is only one universeWe really only need one.It's pretty big. Lotsa room to move around.And one god per universe.That's the rule. You only get one so treat it accordingly.
Original Mike: But the data we have, basically the Kepler and doppler-spectroscopy data sets, are horribly limited.First of all, these days we have significantly more relevant data than that, but the key isn't how many planets we can analyze; it's what counts as "relevant data." In physics, we have very good understandings of how spacetime works and how subatomic particles work (and a mystery of how to put those together mathematically without encountering singularities). From this comes everything else, in particular chemistry, organic chemistry, biology, physiology... but also information theory, probability...So when we build a model from physics as best we understand it, planetary data is a tiny tiny tiny bit of the relevant data the model needs to conform to. It also needs to conform to chemistry, organic chemistry, biology, physiology...Most "scientific models" fail because they don't get anywhere near this close to the fundamentals of physics (or any other hard science, for that matter), and because they think "probability" means "frequency of an event in a repeated 'random' experiment." A combination of both characterizes much of the problem with "climate science," as perusal of, e.g. Climate Audit recapitulates frequently.
"In physics, we have very good understandings of how spacetime works and how subatomic particles work (and a mystery of how to put those together mathematically without encountering singularities)."Actually, there's a hell of a lot we don't know.
When speculating about the universe, or its origin, the real mystery is why it has a mathematical structure. Mathematics is a purely abstract discipline. Knowledge of mathematical theorems does not come from our senses. In other words, this knowledge is not known empirically. if it was, we would have no knowledge of the axioms of perfect geometrical forms.So how is it that purely abstract mathematical knowledge is absolutely necessary for our understanding of the universe? Put another way, why do the laws of a purely abstract discipline "govern" the way the material universe works?
Why would a Super Computer love us enough to do all of that? That is the question that no one believes is real. And that is why miracles are a big part of spreading Christianity.
Basically more beer.
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