tag:blogger.com,1999:blog-17908317.post8102474125307550883..comments2024-03-28T03:15:14.875-07:00Comments on Unenumerated: How to save yourself from chasing futuristic red herringsNick Szabohttp://www.blogger.com/profile/16820399856274245684noreply@blogger.comBlogger14125tag:blogger.com,1999:blog-17908317.post-92125918189064399352015-07-26T08:01:20.614-07:002015-07-26T08:01:20.614-07:00I think your position on astrobiology is quite har...I think your position on astrobiology is quite harsh. Even without a confirmation of ET life, the fact that life has occured once estabilishes a positive probability of this happening else where. In my point of view, it's a worthwhile effort to put lower and upper bounds on the various conditional probabilities in Drake's formula. Two decades ago, we didn't know whether other planets exist around other stars than our own. Now we know. Until just a few years ago, we didn't know whether planets exist in habitable zones around other stars. No we know. We also didn't know whether planets quite similar to our own exist around suns quite similar to ours. Now we know. All these rock-solid astronimical discoveries put lower bound on various conditional probabilites that lead up to the probability of existence of life on those planets and so forth. It might turn out that one element of this product of probabilities is indeed extremely small making it unlikely for us to expect to find life on other planets. But yet, its true science to bound these probabilities and thus gain a better understanding of the universe we live in. Martin Schwarzhttps://www.blogger.com/profile/16935124381866975661noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-39709322027022764362010-04-04T20:05:04.830-07:002010-04-04T20:05:04.830-07:00I once saw a $5 bill on the sidewalk in Palo Alto,...I once saw a $5 bill on the sidewalk in Palo Alto, half a block from University Ave close to Stanford.<br /><br />I laughed out loud but did not even consider picking it up because (a) it might be amusing to the next person, (b) a homeless person might find it much more useful than I would, and (c) it is quite possible someone was doing a yippy econ experiment and I was happy to play the meta joke.Paul Baclacehttps://www.blogger.com/profile/01190461887856072497noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-3726685453810070942009-11-02T00:22:21.178-08:002009-11-02T00:22:21.178-08:00Interestingly enough, switching from the world of ...Interestingly enough, switching from the world of fictional jokes to the real one, I have never in my life found a bill of any denomination lying on a sidewalk. But I've dropped a few, which I promptly picked up.nicknoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-43478983114079369212009-10-31T15:23:41.138-07:002009-10-31T15:23:41.138-07:00There does exist a community living permanently on...There does exist a community living permanently on a cruise ship called "The World". <br /><br />Either way, the "find the easier thing" heuristic reminds me of a joke.<br /><br />An economist is walking through the city with a student. They see a twenty dollar bill lying on the sidewalk. <br /><br />"Look, a twenty dollar bill," says the student.<br /><br />"Nonsense," says the economist. "If there were a twenty dollar bill on the sidewalk, someone would already have picked it up."Race Traitorhttps://www.blogger.com/profile/08076756795873274740noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-32702626413429723532009-10-23T10:44:08.704-07:002009-10-23T10:44:08.704-07:00The megastructure theory is readily falsifiable: i...The megastructure theory is readily falsifiable: if we discover ET that lives on planets rather than inside megastructures, before having discovered any living in megastructures, my theory will have been shown to have very deep problems. So it could be falsified tomorrow if we receive any such signal from a planet that is not accompanied by astrostructures. Even though NASA is so enthusiastic about the raft of new exoplanets that they sent a raft of Trekkie prayers to Gliese 581d recently via the Deep Space Network (on which I used to work), I am about as confident as I can be about any futuristic prediction that we will get no ET signal from such a planet: if you think about the expansionist nature of life and society, and cosmic timeframes, the odds are extremely stacked against it.<br /><br />OTOH, the theory that all ETs remain huddled forever on their little planets is not readily falsifiable: the lack of signals by this theory does not mean that ETI are rare, it just means that ETI are cowardly folk who cleverly hide from astronomers, like elves and leprechauns hide from anthropologists.<br /><br />It is useful to think about what other experiments we could do to get a grip on the probability short of actually observing ETI. Trouble is everything I can think of confirms it: the way plants colonize lifeless areas within a few years after a volcano destroys life, the way humans colonized the earth, the way forests shade most of the sun in their competition for sunlight, and so on. Our observations confirm rather than falsify the idea that life and society are generally expansionist, and it is irrational to expect that all ETI will be otherwise, utopian ideas about "progress towards zero growth" notwithstanding. Even if the stay-at-home civilizations far outnumber the expansionist civilizations, we are far more likely to observe the latter.<br /><br />BTW, I did not mean to suggest that all progress is logistic. In the case of physical expansion it is polynomial or less: cubic (in three dimensions) or square when the vertical dimensions of the galactic disk are reached.<br /><br />This is by no means the most important issue of the day, but it is an area I know well that illustrates your tax money at work. Astrobiology, far more exciting than boring old geology, seems to have become NASA's primary rationale for space science funding, despite it being a science without a subject. For reasons I explain above, astrobiologists have strong incentives to grossly exaggerate the probability of finding ET life. For various reasons I expect the mainstreaming of astrobiology to become the mainstreaming of SETI, and for SETI to become a big justification for NASA's science budget in the future. That may be wrong but it's the trend I'm seeing with the exoplanet discoveries.<br /><br />Far more important is the trillion-dollar debate over climate science. This also seems to involve quite a bit of quasiscience and pseudoscience on both sides, and quite a lot of government-funded scientists who claim they are neutral. Since many people know more about the climate than I, I will leave that debate to others, but some of the general points I make above, that I have learned from observing the debates about future technology and SETI and astrobiology (which I do know quite a bit about) may also apply to the debate over predicting the climate decades out. Are, for example, computer climate models imminently falsifiable? Which climate scientists are willing to make short-term predictions? How do the various scientists, pro or con, justify their funding, and how might this bias their stated or actual beliefs? These and many similar questions related to the above points about futurism may be useful to ask about climate science.nicknoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-15479942942004162002009-10-22T17:54:03.773-07:002009-10-22T17:54:03.773-07:00If you really want to analyze megastructure probab...If you really want to analyze megastructure probability properly you need to combine the logistics curve with unknown unknowns.<br /><br />Take into account that you don't know what you don't know about when structures stop being viable. You can't rule out complex ET, which means astrobiologists get burned coming and going. <br /><br /><br />There's probably something wrong with estimating the probability of truth based on how many ideas you can come up with.<br /><br />It's more that given a large number of possibilities, it's unfeasible even to mount the effort necessary to filter out the crap. Only below some ignorance threshold does the brainstorming process inform you about anything aside from your own brain.Alrenoushttps://www.blogger.com/profile/11119846531341190283noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-37738192374255348942009-10-22T16:57:19.567-07:002009-10-22T16:57:19.567-07:00If it's not clear: by "megastructure"...If it's not clear: by "megastructure" I meant to say dyson spheres (and similar structures).Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-81239718216240835182009-10-22T16:55:24.360-07:002009-10-22T16:55:24.360-07:00nick:
Of course, which is why it's not worth ...nick:<br /><br />Of course, which is why it's not worth spending a lot of time on it.<br /><br />You appear to believe that advanced sentients would go about constructing megastructures; what makes this falsifiable?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-74333370372853046212009-10-22T10:57:45.100-07:002009-10-22T10:57:45.100-07:00Anonymous, you can explain that any possible obser...Anonymous, you can explain that any possible observation is compatible with any pet theory by assuming some arbitrary "new physics." It's completely unfalsifiable. Since one can imagine a nearly infinite number of different pet theories, the chances that any given such pet theory is true is negligible.nicknoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-8415569465942812922009-10-22T08:14:47.917-07:002009-10-22T08:14:47.917-07:00nick: or, you'd conclude there's new physi...nick: or, you'd conclude there's new physics that when discovered would make megastructures like dyson spheres look like a stupid idea to those advanced enough to contemplate their construction.<br /><br />Not much point thinking too much about what that physics might be (if it existed) but as long as you're doing bayesiology you may as well include it as a way of explaining why a galaxy teeming with sentients lacks visible megastructures.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-47459810672071676072009-10-18T22:17:43.208-07:002009-10-18T22:17:43.208-07:00*not* making falsifiable predictions would seem a ...*not* making falsifiable predictions would seem a selection criteria among competing memes. However, Robin Hanson draws attention to the fact that people don't pay much attention to track records, thus making it a weak effect.RomeoStevenshttps://www.blogger.com/profile/11879518218082564987noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-18066481918033942852009-10-18T17:55:39.606-07:002009-10-18T17:55:39.606-07:00George, if like Nick Bostrom and Robin Hanson you ...George, if like Nick Bostrom and Robin Hanson you infer things from astronomy and the Drake Equation that we can get a far better estimate of by observing ourselves, then you want life to be very rare. Because if it is as common as the astrobiologists claim, then there must be a "Great Filter" that brings a stop to evolution about 99.99999999999999999% of the time somewhere between primitive life and building big artifacts like Dyson Spheres that we should be observing in place of unshaded stars and galaxies but don't. Given yet another splendid assumption about distribution functions in the face of ignorance (no such thing as "distribution function unknown" here), a significant fraction of that Great Filter probably still lies ahead of us, so that there is a 99.9999999% chance of humanity being wiped out sometime between now and permanent space colonization. Which means that our already pitifully brief lifespans will likely be cut further short by some imminent disaster. In other words, if we find primitive life on Europa, prepare to die. (Don't quote me on the decimal places, I just kept the 9 key pressed down until I figured it was reasonably representative of their argument).nicknoreply@blogger.comtag:blogger.com,1999:blog-17908317.post-44402426034686965582009-10-18T10:27:53.079-07:002009-10-18T10:27:53.079-07:00Some of these don't seem to be of much practic...Some of these don't seem to be of much practical consequence anyway. I don't know if extraterrestrial bacteria or common, rare, or nonexistent, but if I did believe that they were common, I can't see how it would harm me to be wrong, nor benefit me to be right.George Weinberghttps://www.blogger.com/profile/05384566536853204992noreply@blogger.comtag:blogger.com,1999:blog-17908317.post-23138430065329850382009-10-17T22:39:54.170-07:002009-10-17T22:39:54.170-07:00Polywell Fusion Reactor experiments.Polywell Fusion Reactor experiments.M. Simonhttps://www.blogger.com/profile/09508934110558197375noreply@blogger.com