Pharyngula

Posted by: Matt | August 17, 2010 9:52 AM

I agree, though I am also a *huge* fan of SETI. I was under the impression that their real dedicated budget was rather low, but I may be mistaken. (They have involvements with things like the Kepler Mission -- which is a game-changer of a mission, by the way -- but their whole "search the skies for signals" business model is low-budget.)

Anybody who's anybody in the SETI world, however, only speaks of the Drake equation in hindsight. They are all, with the apparent exception of Shostak, very tentative in saying anything about it. It's a perfectly valid equation, it's just that we (they) don't know anything about almost all of its parameters. SETI folks know this. SETI folks realize this.

Shostak is just doing a PR stunt, maybe. Otherwise I think he's wise enough to say, "Ok, maybe I'm being optimistic."

Posted by: jewbacca.rex | August 17, 2010 9:56 AM

Everyone always forgets about the all-important $B_S$ factor at the end of the Drake equation. xkcd explains.

Posted by: Rorschach | August 17, 2010 10:00 AM

Leonard Nimoy on SETI

Posted by: Marjolein | August 17, 2010 10:04 AM

This

Posted by: Buster | August 17, 2010 10:06 AM

Yeah, but didn't we discover lots of information about quasars and pulsars with SETI? Thing is that finding aliens might not be all its useful for.

In fact, if we did discover aliens and they were advanced enough to come and meet us I guess they'll just come and contemtuously wipe us out.

Posted by: thebat137 | August 17, 2010 10:09 AM

Oh, and, incidentally, I don't really like the lottery analogy. Playing the lottery is a sign of innumeracy because all the probabilities (in a fair lottery, at least) are very well known, and anybody with a little bit of patience can easily calculate the expectation value of the net payout, which is very definitely negative in most cases.

But with SETI, we just really have no idea how big the payout is, or how likely it is, so making a reasonable calculation of the expected net is completely impossible. All we've got to go on in evaluating the wisdom of this gamble are our gut feelings and a few vague bits of handwaving. This doesn't mean that it's wise to invest in a proposition with so many uncertainties, but it's a somewhat different pastime from playing ordinary lotteries.

Posted by: Sajanas | August 17, 2010 10:10 AM

I'm pretty sure that quasars and pulsars were found by regular astronomers, who were then excited that it was some sort of signal. Even if it were the case, it is like justifying the space program because it came up with Tang.
The arguments against SETI are simply that the time they spend using the telescopes could be better served by doing actual astronomy. If they use up spare time that no one else would do stuff with, then sure, have at it, but otherwise, its just as likely that the regular astronomers will find a single while doing their normal work.
I think that the media has overplayed just how far our transmissions penetrate into space (after all, it is spreading out in a giant globe, its bound to become unreadable before it gets very far. And who is to say that alien's haven't just gone fiber optic and don't bother with radio anymore.

Posted by: Tyro | August 17, 2010 10:14 AM

I love Are We Alone so maybe I'm gonna cut Seth some slack.

I agree that SETI seems quixotic and like virtually all other predictions about what will happen 25 years from now, this seems more based on wishful thinking than on any sort of analysis. I think this is a very human failing and not a bigger issue with SETI or Seth in particular. (I'm reminded of a poll which found a majority of Americans thought that within 50 years we had a good chance of both curing cancer and in having the 2nd coming of Jesus. Given the description of the Rapture as being a global war, I wonder just when researchers will have time to devote to curing cancer!)

As for better telescopes & instruments, sure but so what. Buying three lottery tickets instead of one may triple our odds while still leaving them materially unchanged.

Posted by: besserwisser | August 17, 2010 10:16 AM

I agree with you on the drake equation. However, I am pro SETI. It is a long shot they'll find anything but the payoff would be worth it and it's all private money anyway.

Posted by: Chip | August 17, 2010 10:19 AM

PZ
Drake stated that his equation was meant as a "thought experiment" (looking for ref) and was never an actually mathematical equation but was used to illustrate some of the variables that affect life here (earth) and could affect life and intelligence development elsewhere. It has been taken WAY more seriously than he intended as a literal equation by media, some scientists and the UFO crowd. I think the value of the equation is NOT the absolute numbers but the contemplations of the variables themselves that influence "N".
I do play the lottery occasionally and have SETI @ Home running on my computer just because Seth said "if your computer helps find the signal I will share the Nobel prize with you" and I figure it my best shot at a Nobel at this point.

Posted by: Harry Tuttle | August 17, 2010 10:22 AM

What's SETI's budget anyway?

Allen Telescope Array aside (as it is used for non-SETI stuff as well) their budget is about $4 million/year. ALL privately funded.

Would it pay for a single day of the Iraq War?

It wouldn't pay for a single HOUR. Not even with the ATA's $3 million/year added.

Posted by: MoonShark | August 17, 2010 10:27 AM

Aw, I thought I liked Shostak, but this is pathetic.

Posted by: hyperdeath | August 17, 2010 10:28 AM

You can't calculate anything from a formula in which almost all of the variables are complete unknowns

The situation is getting better.

The first parameter (rate of star formation) is well known. The second parameter (fraction of stars with planets) is starting to become more clear, and the Kepler mission could well fix it. Kepler may also shed light on the third parameter (the average number of life supporting planets per solar system) by providing data on the fraction of planets in a temperate orbit. If something like the Overwhelmingly Large Telescope (OWL) gets built, we may be able to get spectra of temperate planets, in which case the presence of atmospheres (and the chemical compositions thereof) could be deduced, thus fixing the third parameter more firmly.

In short, we have 1.5 parameters, and Kepler will probably take us up to 2.5. Something like OWL would take us up to 3.

Of course, parameters 4,5 and 6 (pertaining to life) are a lot more tricky.

Posted by: Nerd of Redhead, OM | August 17, 2010 10:29 AM

Project SETI these days piggy-backs on the Arecibo radio observatory, using unused capacity, and the signals are analyzed using unused computer capacity on a million or so home computers. Very low budget. The servers used tend to be prototypes donated by Cisco and others, and they use open software, and therefore they tend to be unstable compared to a project like Einstein@home, where they can buy good commercial servers and software. Einstein@home also piggy-backs on the Arecibo observatory for some signals (the main signals analyzed are from LIGO). The Arecibo work discovered a neutron star recently.

Posted by: strangeghost | August 17, 2010 10:29 AM

While I don't equate the two pound for pound, the prediction by Shostak sounds a little like the parade of fundamentalist loonies over the years who have set a date for Christ's return. Better to not make predictions that have a significant chance of not coming to pass and only being followed by revised predictions.

Posted by: Dianne | August 17, 2010 10:33 AM

a majority of Americans thought that within 50 years we had a good chance of both curing cancer

Sigh. Probably at about the same time we cure infectious disease. Cancer's not...never mind. You know this already.

Given the description of the Rapture as being a global war, I wonder just when researchers will have time to devote to curing cancer!

If it's a nuclear war there'd at least be plenty of subjects for clinical trials.

Posted by: hyperdeath | August 17, 2010 10:37 AM

...oops I forgot parameter 7 (the average time a civilisation broadcasts for). Arguably, we know this one quite well: It's about 100 years.

Assuming an extraterrestrial civilisation progresses at a similar rate to ours, its the time between the civilisation developing radio, and the civilisation vastly reducing its detectability through the use of cellular networks, highly directional transmitters and spread-spectrum technology.

Earth's radio output peaked during the 1980s. We're now slowly fading into interstellar background noise.

Posted by: daveau | August 17, 2010 10:40 AM

it is like justifying the space program because it came up with Tang.

...And Space Food Sticks. Space program totally worth it right there.

Predicting when we will make contact with an alien civilization is a bit like predicting the end of the world. But more likely to happen someday than armageddon.

Posted by: Birger Johansson | August 17, 2010 10:42 AM

SETI does not consume much resources and does no harm. That said, the search for intelligent aliens has been described as the closest thing to an atheist religion.
This does not mean I question the existence of (primitive) life; there is probably a lot of lichen out there. Getting a sample return probe from a xeno-biosphere would be of enormous importance since it would show alternative ways of organising metabolism and genetic information.

If you wonder why the Milky Way has not been overrun by interstellar travellers already, please read Stephen Jay Gould´s "It´s A Wonderful Life"
For meaningful communication between different "psychozooica" read Stanislaw Lem´s "His Master´s Voice" or "Solaris".

Posted by: llewelly | August 17, 2010 10:49 AM

Buster | August 17, 2010 10:06 AM:

In fact, if we did discover aliens and they were advanced enough to come and meet us I guess they'll just come and contemtuously wipe us out.

Posted by: Dianne | August 17, 2010 10:53 AM

My speculation about intelligent life elsewhere in the universe is this: Yes, there may be life out there somewhere. But it is of absolutely no use to us whatsoever. Either too far away to even ever get to (see previous thread about space travel) or too different to be of any interest or both. I'd be happy personally if we found so much as alien microbes or even fossils of alien microbes. Something with a different genetic basis than DNA or RNA, different structure than protein would be huge. Another culture would be nice too, but then again so would a pony.

Posted by: Mobius | August 17, 2010 10:57 AM

I have to say first off that I am a fan of SETI. That said, I do agree with PZ about the Drake Equation. While interesting in a speculative way, it is utterly useless in any practical manner. If only one of the variables was in doubt, it would end up being nothing more than a very, very rough estimate. With almost all of the variable having unknown values, it becomes nothing more than a WAG (Wild Ass Guess).

Posted by: raven | August 17, 2010 11:00 AM

One thing SETI can do is put a limit on what we know about intelligent broadcasting ETs.

What we know so far is that we have looked and they aren't there. They aren't common in the volume of space that we can and have searched. Nonexistent.

Which brings up another important point. If the galaxy is really empty, someday we could spread out and own the whole thing, 1 trillion stars worth.

Not likely right now but things are always changing. All species are transitional and we've only been doing modern science for 200 years. Let's see what things are like in 3010.

Posted by: Tulse | August 17, 2010 11:05 AM

too different to be of any interest

I completely disagree -- life that is similar to us is of much less interest than life that arose through very different processes.

Posted by: Dianne | August 17, 2010 11:11 AM

What we know so far is that we have looked and they aren't there.

At least, where they aren't broadcasting in bandwidths we can recognize in patterns we recognize. In principle, we could have missed the signal because we weren't looking at the right thing (suppose, for example, they somehow used neutrinos as their communication medium instead of light) or possibly the signal looks like what we think is part of the cosmic microwave background or something.

Posted by: Dianne | August 17, 2010 11:19 AM

I completely disagree -- life that is similar to us is of much less interest than life that arose through very different processes.

I'd be absolutely shocked if there is intelligent extraterrestial life anywhere that is similar enough to humans to be boring. But if it is sufficiently different then we may just not have much to say to each other. Even if we're interested in them, they may want nothing to do with us and refuse to allow us to study their biology or society, for example. In any case, it may be so different that we can not interact directly (ie the aliens require a temperature of 50Kelvin or a gravity of 10G or something similar) and culturally so different that trade and social interactions would be meaningless.

Posted by: Dianne | August 17, 2010 11:27 AM

the window of accidental radio visibility for a typical technological civilization is vanishingly small.

Maybe. We only have an N of 1 to go on. It may be that most alien civilizations use radio signals for thousands of years. Or that even after the major use is over radio has special uses and so a planet with a 20th century-like or later technological base will continue emitting some radio waves, albeit less frequently or less intensively than previously and therefore are still detectible. OTOH, maybe most alien civilizations don't use radio at all.

Posted by: dali_70 | August 17, 2010 11:31 AM

Mr. Shostak is being overly optimistic. Chances are we'll find evidence for past or present life right here in our own little neighborhood long before we ever get a call from ET. Mars is looking more and more like a good candidate for having once been capable of supporting life. Titan and Europa are promising candidates for harboring life of some sort. Thats where we should be looking. The chances are much better of finding something and the scientific knowledge gained would dwarf anything we could get from a million or perhaps billion year old radio signal we'd most likely never be able to understand.

Posted by: Laffo | August 17, 2010 11:34 AM

You're going to feel pretty stupid when the Vogon Construction Fleet arrives.

Posted by: Dianne | August 17, 2010 11:36 AM

You're going to feel pretty stupid when the Vogon Construction Fleet arrives.

Briefly.

Posted by: mineralfellow | August 17, 2010 11:39 AM

PZ, are you honestly so feeble as to criticize a program that has yielded numerous scientific discoveries? The SETI program aims to answer important questions. Others have already pointed out the low cost (or non-cost, as it is all from funding that is not otherwise earmarked for scientific research). Sure, Seth Shostak thinks that we will find extraterrestrial life. If he didn't think so, he wouldn't be one of the main spokesmen for the program he is involved in. But, Drake equation aside, what we observe in the universe is that basically, nothing happens only once. There should be (will be/have been) other intelligences. So why not try to contact them?

Posted by: brodiehannibal | August 17, 2010 11:40 AM

Pointing a telescope at the sky is never a waste of time

this

We are headed for destruction when we stop looking to the sky with curious, scientific minds. The Drake Equation isn’t what I would call good science (im no expert) but I think that it’s pretty unlikely that we are the only sentient life in the universe. I like to think of the Drake Equation more as a place holder for future ideas.

Just imagine, for just a second, the effect that finding life would have on the religious nuts. The worshippin' huts would be very noisy places for a while as they scrambled to reconcile yet another hole in their precious, self centered views about how special and unique they are.

I like Seth. He’s certainly not one of the bad guys. interview here

ok, recloaking now.

Posted by: Vicki, Chief Assistant to the Assistant Chief | August 17, 2010 11:48 AM

From another angle: yes, the odds in the lottery are against you. But you know the money is going somewhere: X% to (usually other) people with winning tickets, and 1-X% to the state government. Someone is going to have a winning ticket, and you can look up/calculate the odds. With SETI, we don't know that. We can work out what's going in: so much spare telescope time, so much electricity from computers running the code instead of being idle, so much programmer and analyst time. But it's less clear what comes out.

I don't think we're likely to find evidence of nonhuman life, for the reasons stated above: but I can think of lots of things that use up more electricity for similar or less value (by which I don't mean that I don't like your music, I mean people leaving the lights, stereo, and TV on when they leave the house).

Posted by: Glen Davidson | August 17, 2010 11:59 AM

Yes, predictions like Shostak's just remind me of all of the "predictions" of how soon evolution/Darwinism will be overturned. They're based on nothing except for a desire to keep people interested in something that produces no results.

The difference is that the SETI folk are doing proper research, and may yet come up with something. If evolution were ever to be replaced by something else we can be pretty sure that the useless boobs at the DI won't have anything to do with coming up with its replacement.

Glen Davidson

Posted by: rcaseybouch | August 17, 2010 12:02 PM

While I agree with you that there is no objective way of estimating when, where, or even if we'll find intelligent life (not that it's even here on Earth to begin with), I must disagree with your rather callous dismissal of SETI as a waste of money.

Humans, by nature, are explorers. Our quest for greater understanding of the universe (in the realm of astrophysics and astronomy) has truthfully surpassed the point at which it can yield practical solutions to human economic problems. But that's not why we continue to stare at the sky.

Why did the United States spend billions of dollars in the 1960s to put a man on the moon? To quote James T. Kirk, "because it's there!"

Although, from its outset, the manned space program seemed to offer little in the way of practical economic incentive; many of the innovations gleaned from it, most notably in the areas of engineering and materials science, have become central parts of modern life.

Why should we colonize Mars (to disagree with an earlier post)? Because it's there and the advances in engineering gained from such an effort would benefit the world.

Similarly, why should we waste time "listening" for extraterrestrial civilizations? Because, although the chances of finding an alien signal are remote, humans need to know that we're not alone in the universe. The question of whether or not there is somebody else out there has been with us since we were hunter-gatherers sitting around a camp fire on the African savanna--to give up on answering it now, when we finally have the means, would be decidedly un-human.

Posted by: Rapscallion | August 17, 2010 12:08 PM

The SETI project has always bothered me because they are not looking for ET intelligent life they are looking for us.

Posted by: https://www.google.com/accounts/o8/id?id=AItOawkG68cqkbcIBGRhfPAvMtIzHIDfJjLHckc | August 17, 2010 12:16 PM

Drake?

Privileged Planet Principle - Michael Strauss - video
http://www.metacafe.com/watch/4318884/

There are many independent characteristics required to be fulfilled for any planet to host advanced carbon-based life. Two popular books have recently been written, 'The Privileged Planet' by Guillermo Gonzalez and 'Rare Earth' by Donald Brownlee, indicating the earth is extremely unique in its ability to host advanced life in this universe. Privileged Planet, which holds that any life supporting planet in the universe will also be 'privileged' for observation of the universe, has now been made into a excellent video.

The Privileged Planet - video
http://video.google.com/videoplay?docid=6308516608498324470&ei=r5EfTNrdMqWSqwLJlOGHCw&q=privileged+planet#

There is also a well researched statistical analysis of the many independent 'life-enabling characteristics' that gives strong mathematical indication that the earth is extremely unique in its ability to support complex life in this universe and shows, from a naturalistic perspective, that a life permitting planet is extremely unlikely to 'accidentally emerge' in the universe. The statistical analysis, which is actually a refinement of the Drake equation, is dealt with by astro-physicist Dr. Hugh Ross (1945-present) in his paper 'Probability for Life on Earth'.

Probability For Life On Earth - List of Parameters, References, and Math - Hugh Ross
http://www.reasons.org/probability-life-earth-apr-2004
http://www.johnankerberg.com/Articles/_PDFArchives/science/SC2W0304RFT.pdf

A few of the items in Dr. Ross's "life-enabling characteristics" list are; Planet location in a proper galaxy's 'habitable zone'; Parent star size; Surface gravity of planet; Rotation period of planet; Correct chemical composition of planet; Correct size for moon; Thickness of planets’ crust; Presence of magnetic field; Correct and stable axis tilt; Oxygen to nitrogen ratio in atmosphere; Proper water content of planet; Atmospheric electric discharge rate; Proper seismic activity of planet; Many complex cycles necessary for a stable temperature history of planet; Translucent atmosphere; Various complex cycles for various elements etc.. etc.. I could go a lot further for there are a total of 322 known parameters on his list which have to be met for complex life to be possible on Earth, or on a planet like Earth. Individually, these limits are not that impressive but when we realize ALL these limits have to be met at the same time and not one of them can be out of limits for any extended period of time, then the condition becomes 'irreducibly complex' and the probability for a world which can host advanced life in this universe becomes very extraordinary. Here is the final summary of Dr. Hugh Ross's 'conservative' estimate for the probability of another life-hosting world in this universe.

Probability for occurrence of all 322 parameters =10^388
Dependency factors estimate =10^96
Longevity requirements estimate =10^14
Probability for occurrence of all 322 parameters = 10^304
Maximum possible number of life support bodies in universe =10^22

Thus, less than 1 chance in 10^282 (million trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion trillion) exists that even one such life-support body would occur anywhere in the universe without invoking divine miracles.

Dr. Hugh Ross, and his team, have now drastically refined this probability of 1 in 10^304 to a staggering probability of 1 in 10^1054:

Does the Probability for ETI = 1?
Excerpt; On the Reasons To Believe website we document that the probability a randomly selected planet would possess all the characteristics intelligent life requires is less than 10^-304. A recent update that will be published with my next book, Hidden Purposes: Why the Universe Is the Way It Is, puts that probability at 10^-1054.
http://www.reasons.org/does-probability-eti-1

Posted by: Steve LaBonne | August 17, 2010 12:20 PM

Who wants first crack at the troll?

Posted by: THEHARMONIKZ | August 17, 2010 12:22 PM

I have to agree,SETI is for the most part a huge waste of scientific endeavour.I never quite understood why the search for E.T has merit at all,of course SETI may have other branches;but that is just a smokescreen for the critics.Lets just invest in what is important for now and leave E.T to Hollywood.

Posted by: KG | August 17, 2010 12:29 PM

In fact, if we did discover aliens and they were advanced enough to come and meet us I guess they'll just come and contemtuously wipe us out.

- Buster

Yes they probably would, simply out of compassion, if they took your level of contact with reality as representative of the species.

Posted by: TheRatKing | August 17, 2010 12:34 PM

I like the Douglas Adams sort of viewpoint on ET and the Universe...

It's much more amusing, and I would love to have a pet mattress called Zem.

Posted by: rcaseybouch | August 17, 2010 12:37 PM

I'll take it...I've got nothing better to do than lurk all day.

Assigning meaningless numbers to determine the "probability" of existence is not a good way to argue for the existence of a divinity.

The universe is a pretty fracking huge place, even if those statistics regarding the probability of life were objectively accurate (which, they're not), improbability does not equal impossibility

An example of that from my own work would be when I was testing a novel protienurea assay which my boss was hoping to use in a drug screen. In order to test it, we had to induce nephrotic syndrome in the animals we were working with; we had a good inducable transgenic model for that but we also wanted to do it with a previously established pharmacological method--puramycin.

Out of the scores of animals (zebrafish, in this case) I wound up injecting with puramycin, the assay only worked once--on one sham-injected fish, which also happened to be the very first one I looked at. The probability that out of the hundreds of animals I looked at, the very first control would have nephrotic syndrome on its own (incidentally, none of the puramycin injected zebrafish ever developed nephrotic syndrome) is astronomically low...but it happened and I have pictures to prove it.

Improbable things happen, that they do is not evidence for the existance of god--it's just a part of how the world works.

Posted by: KG | August 17, 2010 12:41 PM

googlemess@75,76,

You forgot to mention the crucial point: Hugh Ross is a lunatic creobot.

Posted by: Loreo | August 17, 2010 12:56 PM

One tangentially related thing I like about the Drake Equation: It's the basis for Randall Munroe's insightful Flake Equation.

Posted by: Brain Hertz | August 17, 2010 1:05 PM

PS9,
I have to disagree.

As mentioned earlier, I don't share Seth Shostak's optimism. I just don't think we're likely to ever see anything.

However, I don't arrive at the same conclusion you do. About the only think the Drake equation can really tell us is that we can't possibly know; there are just too many unknown and likely unknowable parameters. As such, given the miniscule costs, it makes perfect sense to try. Maybe all we can do is put some upper bounds on the numbers, but we'll still advance our knowledge in so doing. It would be a travesty if there was somebody out there trying to talk to us and we never got the message because we couldn't be bothered...

Your last reason is the worst reason of all not to look. What people will think of you if you fail should never be sufficient motivation to never even try.

Posted by: Dhorvath, OM | August 17, 2010 1:11 PM

The Drake equation is functionally useless for the purpose that Seth Shostak has used. There just isn't enough information about the parameters values. It is a horrible tool for any concrete answers.
It is useful for helping people to understand how quickly small probabilities grow when dealing with astronomical numbers. Unfortunately, these same people tend to get wowed by the way the equation seemingly gaurantees other intelligences in the cosmos. Hence SETI.
What we tend to forget is how many stars are left that won't have intelligent signals, how frequently the stars that do will have their signals directed our way, and how few of those signals will be of sufficient strength for us to notice them. Not to mention what we do when a signal from 1239LY away reaches a receiver here and we realize that no conversation is possible.
SETI would likely do better by focusing on finding nearby solar systems and doing longer term 'listening' to those targets.

Posted by: raven | August 17, 2010 1:13 PM

Hugh Ross is an old earth creationist and all around crackpot. His fine tuning math is just the usual religious kook gibberish.

Sean Carroll, discovermag/cosmic variance blog:

According to Reasons to Believe, the chance of life arising on a planet within the observable universe is only 1 in 10282 — or it would have been, if it weren’t for divine miracles. (Don’t tell them about there are 10500 vacua in string theory, it would ruin everything.) They get this number by writing down a long list of criteria that are purportedly necessary for the existence of life (”star’s space velocity relative to Local Standard of Rest”; “molybdenum quantity in crust”; “mass distribution of Oort Cloud objects”), then they assign probabilities to each, and cheerfully multiply them together.

To the non-crackpot eye, most have little if any connection to the existence of life, and let’s not even mention that many of these are highly non-independent quantities. (You cannot calculate the fraction of “Sean Carroll”s in the world by multiplying the fraction of “Sean”s by the fraction of “Carroll’s. As good Irish names, they are strongly correlated.) It’s the worst kind of flim-flam, because it tries to cover the stench of nonsense by squirting liberal doses of scientific-smelling perfume.

If someone didn’t know anything about the science, and already believed in an active God who made the universe just for us, they could come away convinced that modern science had vindicated all of their beliefs. And that’s not something any of us should sit still for.

Posted by: Mumon | August 17, 2010 1:18 PM

There's a reasonable chance we'll find evidence of extraterrestrial life in a few years, I'd bet, from processes similar to what we have now. But no, one can argue nobody's found intelligent life on earth.

Posted by: AJ Milne OM | August 17, 2010 1:22 PM

Re one question arising here, what happens when/if SETI finds nothing, at any given moment will depend on the larger context...

If the larger context is: we've got spectral data off of hundreds or thousands or tens of thousands of exoplanets, and we've actually found interesting gas mixes in enough places that we've decided maybe life itself isn't actually so rare--that biological stuff does get going often enough--and, indeed, our data set is large enough that we can reasonably precisely bound all the stuff in the Drake equation up to the truly hard stuff--specifically, how often civilizations get going, how often they fry their asses shortly enough after...

But we still haven't seen the faintest sign of anything, anywhere that wants to talk to us, well, then we're facing a somewhat sobering focus on those remaining factors, and have to consider the three following possibilities at least as explanations:

1) However common life itself is, life interested in or capable of broadcasting coherent radio waves is incredibly rare. Hell, for all we know: metazoans aren't so common either, and what we're looking at out there is several dozen soups packed full of whatever the local version of an alga is...

2) Or it just doesn't hang around very long, or

3) We're just not that interesting to talk to.

... from our own somewhat self-interested point of view, the latter two possibilities especially have a certain ominous quality, naturally. And I'm not sure which possibility bothers me more... that all of what we have wrought is unlikely to survive much longer...

Or that we're just incredibly boring.

Somewhat more seriously, I'm still solidly in the 'we don't even know what we don't know' school of thought, here, and generally agreeing with PZ's last paragraph. Prediction in this area is a mug's game. But we should keep looking. Especially at those spectra, soon as we can get them...

Y'know... maybe someday get to the point where at least we know what we don't know. I'm ambitious that way.

Posted by: thebat137 | August 17, 2010 1:28 PM

value of the net payout, which is very definitely negative in most cases.

Are there lotteries out there with a positive net payout ?

Wouldn't that be an ex-lottery by definition ?

Or some sort of money laundering, tax shelter sort of setup.

Heheh, of course you are correct. Especially there's this one.

Posted by: Ordeneus | August 17, 2010 1:31 PM

Well, teh Drake equation may be pants, but the SETI program isn't completely useless, although I think it's more likely to bring about some kind of advance in distributed computing than in communication with little green men. Any suitably advanced program has the potential to spin off unintended advances...

Posted by: nelc | August 17, 2010 1:35 PM

I disagree that the equation is completely useless. At minimum it gives SF writers a handy rule of thumb for universe building.

Posted by: PS9 | August 17, 2010 1:44 PM

#91 - You obviously missed the point. You said:

"Your last reason is the worst reason of all not to look. What people will think of you if you fail should never be sufficient motivation to never even try."

To quote PZ Myers from his topic:

"I'd really like to know if Seth Shostak is innumerate enough to play the lottery, though, because his recent claim that we stand a good chance of discovering extraterrrestrial intelligence within 25 years."

People like Shostak are saying we will find something within a specific time frame.

That is what I was criticizing when I asked what would happen if nothing is found. Why did you make an erroneous assumption and not connect my question to the topic at hand?

Posted by: CJO | August 17, 2010 1:48 PM

It's still not certain how or why we separated from the great apes, it was most likely a huge mutation or a natural error.

Short form (and nobody really knows of course) is that we were selected for bipedal stature in a cooling, drying environment where our cousins kept to the shrinking forests and arboreal habits. And a whole host of consequences came directly or indirectly from that. Visual acuity for surveying the savannah, hands with opposable thumbs freed up for carrying and tool use due to bipedality, larger brain-pan for Mark II wetware, larger birth canal to accomodate same, neoteny to not allow that large brain pan to gestate too long, greater parental investment in helpless, neotonous young, increased sociality to accomodate parenting tasks, language-enabled Mark III wetware to accomodate demands for figuring out what conspecifics are up to in new social arrangements... We became our own niche.

But that took a few billion years of evolution, and hominids have been through some pretty serious population bottlenecks on the way; we very nearly didn't make it, on a number of occasions. And, of course, we're doing our best to kill ourselves off now, and take the rest of the biosphere with us, apparently out of spite.

Posted by: Gaebolga | August 17, 2010 1:55 PM

Citizen of the Cosmos said:

And I'm not sure why a biologist would talk about astronomy while complaining about astronomers who don't know anything about biology.

Once you get into the "probability of life" sections of Drake's Equation, we're in the realm of exobiology, which has some necessary overlap (given the inherently theoretical nature of the field).

I didn't hear PZ bitching about the rate of star formation....

Posted by: James F | August 17, 2010 2:02 PM

Oh, what the heck. Borel's Law!!!11!!!Eleventy!!1

Posted by: Brain Hertz | August 17, 2010 2:05 PM

PS9 #107,

maybe I'm misunderstanding what you're saying. Just to be clear:

1. I don't share Seth Shostak's optimism that we will find anything in 25 years. However, there are so many unknowns that it's very hard to put any useful bounds on the likelyhood of finding anything.

2. I don't consider that adequate justification for not trying. It would be kind of dumb not to look, given the minor cost, even if the result is that we know there's nothing that obvious to find.

When you say:

Worst of all, what happens if SETI doesn't find anything? That will just embolden the rabidly religious into assuming they were right. ("See, 'god' only made us, and made the universe for us!") That's not doing science, scientists and the public any favours.

If you're saying that this is justification for not looking, then I disagree. If you're only saying that it's justification for not being optimistic about it, then I can see your concern. However, I'd also have to say that being optimistic about a positive result is probably a prerequisite for having somebody dedicate themselves to the problem...

Posted by: Ewan R | August 17, 2010 2:26 PM

The most recent calculations, I think, put it at about 2 to 3 lightyears before it becomes pure gibberish.

Or in the case of fox news broadcasts approximately 6nm

Posted by: Multicellular | August 17, 2010 2:37 PM

Why is Shostak predicting we'll find aliens within the next 25 years? Simple, no bucks, no Buck Rogers.

The reality is we have no clue as to the odds of finding intelligent life but if we are to investigate the chances the bottom line is you need money. Shostak isn't dumb and knows how to pander for donations - 25 years is a good number to throw out because those who might choose to donate stand a good chance of being alive in 25 years. If he'd said 50 or more years most people probably wouldn't choose to donate since they'd realize they probably wouldn't live to see the payoff of their "investment". SETI is the fusion power of astronomy, until it actually happens (don't hold your breath) detection of an ETI will always be 25 years off.

I also found it funny that in a previous post PZ mentions Vic Stenger's critique of the "absence of evidence isn't evidence of absence" argument. This is the same phrase used often by SETI. I always thought this is a horrible comment to hang the SETI hat on.

Posted by: Greylander | August 17, 2010 2:52 PM

I have to agree on this one.

Use of the Drake equation ranges from something a bit less than an educated guess to pure whimsy.

They way I look at it is this: it took 4 billion year, about 1/3 of the lifetime of the whole freakin' universe, for intelligent life to evolve on this planet. It is entirely plausible that that was *fast*.

I would argue that evolution of intelligent life is inevitable on a planet with earth-like potential, but as to whether 4 billion years is typical, extremely fast, or extremely slow, we have no way of knowing.

I lay odds that 4 billion years is an extremely fast incubation time for intelligent life to evolve for the following reason. Once intelligent life reaches current earth levels, it is on the verge of taking off technologically. Memes are taking over as the principle replicators, relegating bio-chemical replicators (DNA in our case) as mere tools. Like any other replicator, the memes that reproduce and expand into new niches... are the ones that expand and reproduce into new niches. Memes will propagate themselves through their blended biological/machine carriers., utilizing all accessible resources. Not subject to biological limits of DNA, memes mainly just need energy... and will expand to make use of all availalbe energy in the solar system... our unrecognizable-as-human bio-machine descendents, which probably will not be even recognizable as distinct "individuals" in any contemporary conventional sense, will necessarily expand outward toward the stars (interstellar travel limitations from the PZ's early blog post of biology, lifespan, and energy will be irrelevant at this stage). Once started, the expansion will be extremely rapid... pushing a significant fraction of the speed of light. This is going to happen within about 1000 years of reaching "21st century terran" level of development.

(**For those who care and know what I'm talking about: it is around this time that a simulated cognition construct of George R. R. Martin will finish his Song of Ice & Fire Series.**)

Any civilization which is ahead of us is probably going to be be many tens of thousands or millions of years ahead of us and already well beyond the state that I have just described (the odds that they develop within less than a million years of us might as well be "simultaneous" on the scale of cosmic time -- and so extremely unlikely... other "1st century terran equivalent civilization" will come long before or long after our own). So if a civilization came before us within our own galaxy... then we rightly ask: where the hell are they? They are either intentionally leaving us alone or they are not there*. BTW -- they don't need or care about our real-estate... all they need is raw matter and energy and there are plenty of stars and hydrogen gas clouds providing plenty of that. They could afford to leave primitive life to evolve on it's own. Maybe we are their entertainment. "Meerkat City" anyone?

* One other possibility is there is yet much, much more to the universe than we are presently able to guess ("extra dimensions" or what have you) such that what we think of as the "known universe" is simply left behind by any civilization this advanced. BUT there is a problem with that which is: replicators tend to expand to fill all available niches... so while some meme-driven life may "move on" to bigger and better things than our know universe... there should still be meme-driven life that pokes its way into every nook and cranny (the insects of the meme world?).

The upshot is, if they were "out there" seems most likely they would already "be here". They seem not to be, so it seems they are not.

Nothing says we can't be the first intelligent life in our galaxy... maybe even in our region of the known universe... hell maybe we're the first all the way out to the Cosmic Microwave Background.

Posted by: Demonax | August 17, 2010 3:01 PM

As a non-American my first vist to Fox News on the television convinces me that aliens are with us already.

Posted by: amphiox | August 17, 2010 3:28 PM

I touched on this on my last comment, but that was held in moderation, so....

You can't actually even say that biologists have amended the biology-related values to something more "reasonable" because for the purpose of calculating odds, everything biological is based on just earth and that's a sample set of 1, and you cannot make any reasonable evidence based pronouncements on probabilities with N=1.

Evolution is contingent you say, and dependent on unpredictable environmental changes? Absolutely true, but every earth like planet with life can be expected to produce billions of lineages and trillions of species. Every earth-like planet (by definition, in fact!) will have a habitable span of at least 3 billion years. Every earth-like planet will be expected to have a history of radical environmental change, and host a great diversity of environmental conditions at any given point in time.

So you can say that it took trillions of species over nearly 4 billion years before just one achieved a technological civilization on earth, and so the odds of it happening elsewhere are very low, or you can say that every earth-like planet will generate trillions of species adapting to diverse an changing environments over several billion years, and the odds of at least one of those species, at some point in that time span, achieving a technological civilization, becomes, based on available evidence, close to 1/1=100%.

You can intelligibly use evidence to decide between these two scenarios without first finding at least one other example of an intelligent civilization, to make your N=2.

Posted by: raven | August 17, 2010 3:31 PM

If we aren't even searching, then we aren't going to find a goddamned thing.

True. The first rule for finding anything.

Posted by: jfbode1029 | August 17, 2010 3:48 PM

@raven #47

One thing SETI can do is put a limit on what we know about intelligent broadcasting ETs.

What we know so far is that we have looked and they aren't there. They aren't common in the volume of space that we can and have searched. Nonexistent.

Well, what we know so far is that nobody in that area is currently broadcasting using the kind of technology we're able to detect, which is a different statement from saying there's nobody there.

All of the following scenarios are possible:

plus at least a half-dozen others I'm too lazy to enumerate.

We only became "noisy" in the last century; anyone pointing a radio telescope at us wouldn't know we were here unless they were looking right now and less than a 100 light years away.

Personally, I'm convinced the universe must be lousy with life, most of it microbial, a tiny fraction of it intelligent, but given distances involved, the chances that we'd find each other is beyond remote. I'm not at all optimistic that we'd find evidence of intelligent life on another planet.

Posted by: Nerd of Redhead, OM | August 17, 2010 4:07 PM

How much does SETI actually cost, anyways?

Posted by: amphiox | August 17, 2010 4:12 PM

This doesn't address the problem. It's entirely conceivable that human intelligence is a one-off freakish evolutionary dead end, a monstrosity like the antlers of the Irish elk. At present we just have no way to know.

Oh, I absolutely agree. That was the point of that post, but perhaps I didn't phrase it in the clearest way. Both arguments are equally likely, or equally unlikely, because we have no way of knowing.

But I do want to point out that even freakish evolutionary dead ends can, given enough trials/time, happen more than once. It all depends on exactly how freakish they are, and in what manner of freakishness, which again we have no current way of knowing.

It still remains quite fun to guess, of course.

Posted by: amphiox | August 17, 2010 4:22 PM

Most of what SETI does, as I understand it, is piggy-backing onto telescope time used for other projects.

So for all intents and purposes, SETI is basically free. The financial argument against it doesn't hold.

Posted by: Lotharloo | August 17, 2010 4:44 PM

So basically, biologists don't understand how big is space and physicists don't understand how unlikely is intelligent life.

Posted by: Kagehi | August 17, 2010 5:13 PM

The servers used tend to be prototypes donated by Cisco and others, and they use open software, and therefore they tend to be unstable compared to a project like Einstein@home, where they can buy good commercial servers and software.

Depends on who is writing the code. Seriously. Often open source is **way** more stable than some so-called professional software, and if it has a bug, you don't wait months, or years, for someone to get around to fixing it. If you mean the OS, server code, etc, then.. Well, just look at the joke you get with people like Ubuntu, or Red Hat, etc, where their "open" versions are often more stable than their commercial ones, because the bugs get patched, which get overlooked, or sidelined, in order to ship on time.

However... A lot of code for astronomy and other fields gets written by people "in house", including those lovely "commercial" applications for doing science, and... let me put it this way, a review of their coding practices not too many years back found that **many** people in the sciences where hand coding things in notepad, had never even *heard* of IDEs, and, in many cases, had no damn clue that other languages, besides machine language and C, (no, not even object oriented C++, but "C") existed. This wasn't, btw, "open source", in any sense of the word, since they tended to keep projects close to the vest, and about 90% of them simply flat out failed, or couldn't be debugged at all. I doubt this practice has changed a huge amount, so.. superficially, having professionals write something *may* be more stable than the in house stuff, that had a high failure rate, but it does not follow that, if good open source, and IDEs, etc., have found their way in, that the open source systems wouldn't be, in fact, more stable, with less down time, just like most of the services that run the internet, which operate on things like Apache, and Linux, and other open source servers.

Posted by: llewelly | August 17, 2010 5:52 PM

jidashdee | August 17, 2010 11:32 AM:

A huge portion of our population will believe that the signal was faked or mistaken.

Posted by: Steve | August 17, 2010 6:07 PM

This is one of those rare cases where I disagree with PZ. I run SETI@Home on my computer, because, although I do realize there are a lot of unknowns when it comes to the Drake equation, I do think it's still worth it to at least LOOK for ET. The overall cost is very small compared to so many things...so why not? What's the harm? Unlike with God and other supernatural entities, at least with ET there's a real chance it actually exists, and wouldn't that be cool if we picked up a signal!

Posted by: amphiox | August 17, 2010 7:30 PM

If, for example, it turns out that the number of ETIs is something around 1 per galaxy per 0.5 billion years and each lasts 10 000 to 100 000 years in a detectable state, that would mean the universe is literally teeming with ETIs (there are trillions of galaxies) but humans would still be effectively alone. We would have absolutely no chance of meaningful contact with any of them, and almost no chance of ever even detecting them.

Posted by: Jackson | August 17, 2010 7:42 PM

@4: I'm a fan of SETI but xkcd's comment on Drake equation scores.

Posted by: Ichthyic | August 17, 2010 7:44 PM

He could win the lottery. But I'm not going to place any bets on it.

OTOH, people DO win the lottery, and you can't win if you don't even play.

Posted by: Ichthyic | August 17, 2010 8:39 PM

So there must be civilizations BILLIONS of years old.

no.

you seem to think that civilization must be some continuous thing since its primary inception.

our own history puts the lie to that.

It may be the theists have a truer imagination in some sense

no, just more credulous.

Posted by: pjsouza | August 17, 2010 9:34 PM

There must be something with biologists with the letters M Y R in their surnames that makes them hate SETI. I remember a debate between Sagan and Mayr this, where Dr. Mayr said it was a futile endeavor. Well I for one with Ichthyic and Timrowledge, and hopefully many others (I didn't read all the comments). Also, sometimes it's not about the destination, but about the trip.

Paulino

Posted by: MadScientist | August 17, 2010 11:57 PM

@150: I can't imagine the "appearing like gods" bit. We know there are no gods and we know enough of the way nature works that anything presented to us by aliens may be stupefying but I cannot imagine people associating unknown technology with gods. That may have worked if our society believed in the Ceilingcat, so if you took an MP3 player to some remote part of the earth where superstition were rampant and knowledge of nature very poor I would have no doubt that the locals may think of it as magic and the work of spirits or gods. However, if you stepped back a bit in time and showed it to, say a DEC engineer in 1968, I would expect the reaction to be "awesome, how did you do this?" and not "Wow! Are you some sort of god?"

Posted by: amphiox | August 18, 2010 12:03 AM

I can't imagine the "appearing like gods" bit. We know there are no gods and we know enough of the way nature works that anything presented to us by aliens may be stupefying but I cannot imagine people associating unknown technology with gods.

We'd know they would not be gods, but it is possible that the things they can/will do will be so stupefying that the best description we can come up to desribe it will be "god-like".

Posted by: amphiox | August 18, 2010 12:08 AM

So there must be civilizations BILLIONS of years old.

Might be. Must? I don't think so.

Keep in mind also that as we tick back into the billions of years, stellar metallicity drops and the likelihood of planet formation drops. Our sun has a higher metallicity than most stars of it's age, which means that we in this solar system essential had a leg-up as it were, a head start compared to most other solar systems of similar age. Though of course there are more than enough stars out there with metallicity even greater than our sun's to nix this as a "we are alone" argument. But it could easily mean that we are in one of the earlier cohorts.

Posted by: John Morales | August 18, 2010 12:15 AM

amphiox:

For any other kind of signal, I imagine we'd be spending decades, if not centuries, trying to decode it.

For all you know, radio might just be the equivalent of using smoke signals — fine for short distances, no good for intercontinental communication.

Are we up to detecting modulated neutrino pulses, or gravity waves, or something more exotic?

Posted by: amphiox | August 18, 2010 12:28 AM

Suppose SETI succeeds in locating another technological civilization. What would we gain from that? True, it would be interesting, but we could hardly hope to learn much except that there is somebody out there.

From the nature of the signal we detect we will learn something about the alien technology used to create that signal. If it is substantially different from the kinds of signals we ourselves are capable of generating, we might discover an entire new area of communications technology, or at least learn that such a thing is possible.

From the strength of the signal we will get a guage on how much energy the originating civilization used to produce it, and from that we'll get an estimate of how much energy the alien civilization is capable of producing and controlling. If it is substantially more than what we can produce, we'll learn that it is possible for a civilization to obtain and exploit much more energy that what we are able to (and harming our own environment to achieve), and thrive in the process. If it is substantially less than what we ourselves can produce, then we'll learn that it is possible to be far more efficient in energy usage, and still produce a technological sophistication superior to our own (remember that we cannot actually send a signal ourselves at this present moment).

From the location of the signal we'll learn what kind of galactic region the alien civilization is in, and we'll be able get some answers to the question of what kinds of galactic locations are amenable to the development of intelligent life, and whether or not our location in the Milky Way is somehow special or unique.

From the distance of the signal we'll know how old the alien civilization is, and that will give us some hint as to how long our civilization might survive.

When we identify the star the signal comes from, we'll be able to search for planets in that star system. We'll learn from the nature of those planets what kinds of planetary environments allow for the development of intelligent life. If we find no earth-like planets there, we'll learn that earth-like conditions are not required for the development of complex life. And if we find no planets at all, or the star is a very young star around which there hasn't been sufficient time for complex life to evolve, then we'll know that either life doesn't even require planets to develop on, or that colonization of other star systems is, in fact, possible, doesn't even require planets as habitable destinations, and something we should consider devoting effort and resources to.

And if there is actual information in the signal, in the process of trying to decode it we will learn new tricks about the transmission and coding of information, and about ways of perceiving and experiencing the universe that are different from our own.

We can hardly hope NOT to learn much from detecting an alien signal.

Posted by: John Morales | August 18, 2010 12:43 AM

From the strength of the signal we will get a guage on how much energy the originating civilization used to produce it, and from that we'll get an estimate of how much energy the alien civilization is capable of producing and controlling.

For that, you also need to know the point of origin and whether it's a narrow or wide beam.

From the location of the signal we'll learn what kind of galactic region the alien civilization is in

Again, you'll have a direction vector, but are redshift and degradation reliable indicators for the distance?

We'll learn from the nature of those planets what kinds of planetary environments allow for the development of intelligent life.

Is intelligence necessarily associated with life?
It might be The First Sirian Bank. :)

We can hardly hope NOT to learn much from detecting an alien signal.

True. But, mainly, that there are alien somethings out there.

Posted by: John Morales | August 18, 2010 12:59 AM

amphiox:

What our own history shows is a jagged-toothed pattern of rising and falling civilizations.

Yes, for some tens of thousand years or so, starting at zero (unless actual evidence of the Old Ones comes up), and with no global-extinction-level events so far.

Not much of a sample from which to extrapolate millions, let alone billions.

Civilizations fall, but civilizations rise again.

And, if there had been a dinosaur civilisation 70 million years ago, would you expect to find evidence of it now?

Posted by: John Morales | August 18, 2010 1:26 AM

amphiox:

Unless you believe in divine creation and do not consider gods to be alive.

Are you really so sure condensed matter substrates are essential to life? So sure that Star Trek "energy beings" or Benford's "magnetic entities" are not possible?

You might wish to consider what it is that defines 'life' (say, self-organising homeostatic entropy sinks). But then, by that definition viruses aren't life. :)

I guess I'm saying you seem to be making a lot of assumptions, here.

Posted by: amphiox | August 18, 2010 1:38 AM

Are you really so sure condensed matter substrates are essential to life? So sure that Star Trek "energy beings" or Benford's "magnetic entities" are not possible?

No, I am not. But I consider all these things to qualify as "life", which you seem to have assumed that I do not.

At any rate, even if you do not consider these things to be alive, for these things to exist, there must be some plausible evolutionary sequence be which they are either directly or indirectly generated. And somewhere on that sequence there will certainly be something that will fit someone's definition of "life".

Posted by: Ichthyic | August 18, 2010 1:46 AM

If they engaged in open-pit mining through bedrock,

Wait, I have documentary footage of that...

http://www.youtube.com/watch?v=2PPf3aaZmUw&feature=related

Posted by: amphiox | August 18, 2010 1:53 AM

re #173;

And as a I recall, there is a certain website (which will not be named) with a certain ideological bent (which will also not be named) which is currently the subject of another ongoing thread (which will also not be named), which really does seem to consider that to be documentary footage. . . .

Posted by: danielm | August 18, 2010 2:02 AM

This is the closest thing to an atheist shouting "heretic!" since, oh, yesterday, when there was a general clamouring of voices claiming that brain emulation would never, ever, ever, under any circumstances be possible because fuck you that's why.

SETI is a cheap program which seeks to answer one of the fundamental questions left to free-thinking intelligent life on this planet - it does no harm, promotes no woo...although, like any other endeavour, woo attaches itself rather easily, along with ignorance, and makes optimistic people sound like raving loons.

The Drake equation is a thought experiment, and until we DO know more about the variables we currently know very little about, we won't be able to come up with an entirely satisfactory answer, but that doesn't mean we shouldn't try - and more to the point without programs like seti we will never be able to plug in those missing variables.

Since when has bloody-minded ignorance EVER been a good deal?

For a good investigation of the question, try Asimov's "extraterrestrial civilisations". I bought it second hand and it's a very interesting read - and it doesn't mention the drake equation.

And yes, whoever was talking about "free software" being less reliable than purely commercial is talking out their ass. The internet and the majority of the servers upon it run free software.

Posted by: Ichthyic | August 18, 2010 2:07 AM

which really does seem to consider that to be documentary footage. . . .

yeah, it just never gets old, eh?

;)

Posted by: John Morales | August 18, 2010 2:25 AM

danielm, you seem to misread PZ. Re-read the OP.

If he were against SETI, he'd have made it clear.

If he thought the Drake equation was only a thought experiment, he'd probably have lain off.

But he quoted Seth Shostak, senior astronomer at the Search for Extraterrestrial Intelligence Institute in Mountain View, Calif., saying "Young people in the audience, I think there's a really good chance you're going to see this happen.", and that Shostak bases this estimation on the Drake Equation.

That is what he poo-poohs.

Posted by: stubotics | August 18, 2010 7:04 AM

This website has podcasts by a number of SETI Institute speakers including Frank Drake:
http://www.astrosociety.org/education/podcast/index.html

And I agree with a lot of commenters - the budget is so low, the question so important, and the potential payoff so huge that there is no reason we shouldn't be listening/watching for ET.

Posted by: McCthulhu is taking ∞ to eat all the pi | August 18, 2010 9:33 AM

Not long ago, for a lark, I decided to put down the numbers that seemed right to me for the Drake Equation. For an answer to the question 'How many intelligent civilizations are there in the galaxy?' I got an answer of exactly .25. Kind of depressing, but then I had to laugh...if we're it for the entire galaxy, only 1/4 of humans really are intelligent. The rest are waiting for the Rapture or flying into buildings or sitting on the floor and picking their noses and thinking of dirty things.

Posted by: Vicki, Chief Assistant to the Assistant Chief | August 18, 2010 12:29 PM

Amphiox, one quibble:

The distance of the signal doesn't tell us how old the sending civilization is. It tells us how long ago the signal was sent. But it doesn't tell us whether the civilization still exists (which is one meaning of "how old," or how old it was when the signal was sent, which is the other useful meaning.

It's like getting a message dated "March 4, 1946": I don't know from that how old the sender was when she sent the message, or how long she lived after that.

Posted by: llewelly | August 18, 2010 1:35 PM

John Morales | August 18, 2010 2:25 AM:

But he quoted Seth Shostak, senior astronomer at the Search for Extraterrestrial Intelligence Institute in Mountain View, Calif., saying "Young people in the audience, I think there's a really good chance you're going to see this happen.", and that Shostak bases this estimation on the Drake Equation.

The reporter claims Shostak bases his estimation on the Drake equation. The quote in the article only refers to the time frame - not what Shostak based his estimation on. Maybe Shostak based his estimation on the Drake equation when the reporter was there, but that is not what Shostak wrote in his recent book Confessions of An Alien Hunter, as I explained above. Given the propensity of reporters to misunderstand what scientists say, I suspect what Shostak said was closer to what he wrote in his book, rather than the reporter's vague description; his estimation is based on "Moore's law", and on the resources necessary to scan every star in the galaxy for the existance of an always-on omnidirectional broadcaster. Shostak is too optimistic about the potential existance of always-on omnidirectional broadcasters (my opinion), and the chances of detecting intermittent and/or directional broadcasters (which he covers in his book), and probably too optimistic about "Moore's law", but his estimation (as described in his book) is not based on the Drake equation.

The important take-away item: if "Moore's law" holds out for another 25 years, we'll know beyond a reasonable doubt whether or not there are easy-to-detect civilizations sharing the galaxy with us. (I suspect the anser will be "no", but Shostak thinks otherwise.)

Posted by: llewelly | August 18, 2010 1:46 PM

Kaleberg5 | August 18, 2010 12:09 AM:

Otherwise, we might find ourselves in serious trouble if we get caught violating some alien DMCA. Breaking DRM is illegal on earth; it might also be illegal in space, and some of those aliens, like the RIAAliens, might be bad-ass. SETI isn't some noble cause. It's just about stealing.

Posted by: «bønez_brigade» | August 18, 2010 4:41 PM

@Kaleberg5 [#160],
If there's any hard evidence to be found that we've been visited by asshole aliens, your RIAAlien (and MPAAlien) fucks are good candidates.

Posted by: danielm | August 18, 2010 5:51 PM

@181 john morales
I was, perhaps badly, referencing not only PZ but also others making quotes.

For the PZ specific part, he doesn't like SETI, and I take that to mean he's against it - when all evidence points to it be immeasurably useful and costing a pittance. The same could be said of the space race - it provides shedloads of new technology which we find pretty useful down here to start with, and gives us a leg up there, which may or may not be very, very useful some day soon.

You're right about the timescale being a big issue to some - though it's debatable as to whether it's the biggest point. The biggest point seems to be...well...ignorance on the part of many about the universe we live in. Simple math (and you should really go read some of the articles and books linked to here about this) dictates that the raw number of available planets for life are quite probably in the many millions in this galaxy alone, making alien life common and intelligent life rare, but hardly impossible.

Add to that knowledge the facts about increases in computing power, increases in technology, increases in the availability of resources and techniques to search for planets and all of a sudden the idea that we've past some sort of watershed doesn't really look all that unlikely.

So the reporter said this, that or the other - really, people should know better than to believe everything a reporter says. If they don't, boy do I have a bridge to sell 'em...

Maybe we won't find intelligent aliens - what we will have is far more information on where they're not, and whilst that might not sound like much it's a darn sight more information than we have now and light years beyond what we had even ten years ago.

@182: really, the brain-emulation thing comes out as "no fucking way can we do it, ever" whichever way the majority of the comments are sliced, yet nobody really knows why. PZ's argument is that we don't know enough about the biology...but we don't need to know it if we either simulate the universe and let it's own simple rules do their thing (not that that's easy!) or if we build something which works like the brain does without the whole messy biology thing.

Life might not be clockwork, but if nature can do it, I fail to understand why it can't be replicated artificially. It's hardly being an intelligent design proponent (HRRRK-spit) to say that whilst natural birds can fly, we can build airplanes that do it better, is it?

Now, 25 years? well...maybe not. cold fusion has been 25 years away for how long now? The difference is that there's been a quiet renaissance in AI. Now we have predictive algorithms, robots like asimo, autopilots for cars that can drive across the country unaided using GPS. AI is here, right now. We're missing general AI but we're getting a feel for those missing pieces now. The same could be said about brain emulation - those huge toys that've been poopoo'd for being a PR stunt ARE useful and really are something which might, just might, take us somewhere.

But really, PZ's argument about not knowing how all these proteins fold? not much of an argument. I would suggest that if Kurzweil doesn't know biology, then PZ doesn't know AI and cognitive science. Shocker, I know.

Posted by: https://www.google.com/accounts/o8/id?id=AItOawlGPCV93W4d3PEtCF3uGL-SeL4Rgf0eRfk | August 18, 2010 6:18 PM

Nick Bostrom,
I read your essay and one big stumbling block for your argument is that there might be alien civilizations out there, that are billions of years old and unimaginably sophisticated - but they leave us alone or don't want us to know about them, for ethical reasons, or whatever.
This doesn't seem at all unlikely. Interfering would cause a cultural trauma worse by many orders of magnitude than anything the missionaries do.
It's not as if our efforts so far make it likely that there's nobody out there. Michio Kaku commented on how little of the sky we've searched; how aliens might split up their communications so that any particular wavelength looks like random noise.
Or maybe they do interfere or visit, but subtly, always hiding behind Occam's Razor as anyone does who wants to hide, (so the easier explanation of anything people notice is something mundane).
Or maybe we did get seeded by an alien civilization a long time ago.

Posted by: CJO | August 18, 2010 6:27 PM

But really, PZ's argument about not knowing how all these proteins fold? not much of an argument. I would suggest that if Kurzweil doesn't know biology, then PZ doesn't know AI and cognitive science. Shocker, I know.

Read the post in question again, because you didn't understand the argument. Kurtzweil is extrapolating from irrelevant information (the size in information theoretical terms of the human genome) in order to make the case that simulating a functioning, aware human brain shouldn't be that hard with increasing computing power. But when you realize that the genome is much more analogous to a recipe than a blueprint, it's a non sequitur. Calculate the information content of a cake recipe, and compare that in terms of "lines of code" that it would take to program a detailed, molecular-level simulation of a batter baking into a cake. There's no relationship.

the brain-emulation thing comes out as "no fucking way can we do it, ever" whichever way the majority of the comments are sliced, yet nobody really knows why. PZ's argument is that we don't know enough about the biology...but we don't need to know it if we either simulate the universe and let it's own simple rules do their thing (not that that's easy!)

No, it wouldn't appear that it is that easy to, as you blithely say, "simulate the universe." Many, many very smart people are expending considerable ingenuity right now just to devise adequate simulations of very small parts of the universe, and solutions that apply across phenomena are not thick on the ground.

or if we build something which works like the brain does without the whole messy biology thing.

LOL. We need to understand "the whole messy biology thing" in order to know what it means to say a system "works like the brain does." IOW, you've skipped the messy biology and you have a system you think works like the brain does. How would you know you were wrong unless you knew how the brain works?

Posted by: https://www.google.com/accounts/o8/id?id=AItOawlGPCV93W4d3PEtCF3uGL-SeL4Rgf0eRfk | August 18, 2010 7:07 PM

"I can't imagine the "appearing like gods" bit. We know there are no gods and we know enough of the way nature works that anything presented to us by aliens may be stupefying but I cannot imagine people associating unknown technology with gods."

That is a really surprising thing to say given how many people believe in God or something supernatural.
But I wasn't claiming that people would necessarily permanently think that aliens were something supernatural. Maybe God or Gods exist and are a natural phenomenon (as super-advanced aliens).
"Studying" super-advanced aliens would be radically different from any kind of study we're familiar with, because we know about studying non-intelligent natural phenomena; things that can be replicated in controlled conditions. It would be vastly more complicated to try to understand the actions of independent beings as natural phenomena. We'd be trying to understand non-reproducible phenomena, and it might look like something supernatural.
Especially if an alien civilization didn't want us to know about them.
Yes, it's possible that there's some law that any advanced civilization kills itself off because of some technology they discover. It seems unlikely this would inevitably happen because of war, because intra-species aggression doesn't sound like something that's inevitably a precondition for evolving an advanced civilization.
But maybe there's some booby trap technology where a civilization unexpectedly makes a black hole that swallows them. Maybe the black holes drifting around are graveyards of civilizations. But it seems like a weird idea that such a thing would be inevitable.
Or maybe civilizations get content and stop developing after they've conquered Death and Disease and War; but before they're like gods. Again it seems a weird idea that this would be inevitable.
So the idea of godlike aliens - somewhere - seems fairly robust.

Posted by: David Marjanović | August 18, 2010 8:39 PM

About 24 h ago I tried to post a comment that got held up for moderation. I don't understand why, so I'm posting it piecemeal (it still hasn't made it through moderation). Second part:

==============

Much of the Internet runs on Linux. Viruses run on Windows.

The reason most (not all!) viruses run on Windows is that most computers run on Windows. Supply and demand.

Circularly, that's among the reasons why so much of the Internet runs on Linux.

Why did the United States spend billions of dollars in the 1960s to put a man on the moon? To quote James T. Kirk, "because it's there!"

No, that wasn't the reason. "Not because they are easy", and not "because they are hard".

The reason was that those dastardly Russians would otherwise have done it first. Without a Cold War, there's no incentive.

Two popular books have recently been written, 'The Privileged Planet' by Guillermo Gonzalez and 'Rare Earth' by Donald Brownlee

The Privileged Planet is a collection of creationist half-truths. Rare Earth by Peter D. Ward and Donald Brownlee is science. You're trying to parasitize on its respectability. You should be ashamed.

A few of the items in Dr. Ross's "life-enabling characteristics" list are; [...] Correct chemical composition of planet; [...] Thickness of planets’ crust; Presence of magnetic field; [...] Proper seismic activity of planet;

Isn't this four times the same parameter?

Oxygen to nitrogen ratio in atmosphere; [...] Atmospheric electric discharge rate; [...] Many complex cycles necessary for a stable temperature history of planet; Translucent atmosphere; Various complex cycles for various elements etc.. etc..

All this is done by life. Where does oxygen come from? From photosynthesis. What does the carbon cycle of Earth mostly consist of? Photosynthesis and respiration. Nitrogen? Nitrogen fixation and denitrification. Translucent atmosphere? One without organic sludge = one with oxygen = one produced by photosynthesis. And so on ad nauseam.

Why do people laugh at creationists?

Only creationists don't understand why!

It's still not certain how or why we separated from the great apes, it was most likely a huge mutation or a natural error.

Mutations are natural errors, nothing huge was involved, and we are great apes – the chimps + bonobos are more closely related to us than to the orang-utans.

Posted by: John Morales | August 18, 2010 9:03 PM

danielm:

(and you should really go read some of the articles and books linked to here about this)

Sigh.

You perhaps should "really go read" what I write.

Posted by: John Morales | August 19, 2010 12:04 AM

Um, PZ. David worked it out @206.

But nice of you to confirm it. :)

Posted by: John Morales | August 19, 2010 1:18 AM

llewelly, your quibbles are noted, though I also note you (a) emphasised that it was what the reporter reported and (b) claimed "The quote in the article only refers to the time frame - not what Shostak based his estimation on.".

Which it actually did.

Now, did or did not the reporter write that Shostak said "Young people in the audience, I think there's a really good chance you're going to see this happen", and did he or did he not base this on both the Drake equation and his perception of Moore's law?

--

PS (this isn't addressed to you, but to those who may be unaware of it): Moore's law (original formulation)
The complexity for minimum component costs has increased at a rate of roughly a factor of two per year... Certainly over the short term this rate can be expected to continue, if not to increase. Over the longer term, the rate of increase is a bit more uncertain, although there is no reason to believe it will not remain nearly constant for at least 10 years. That means by 1975, the number of components per integrated circuit for minimum cost will be 65,000. I believe that such a large circuit can be built on a single wafer.

--

PPS As an aside, was Turing awesome or what? From the same source: "Alan Turing in a 1950 paper had predicted that by the turn of the millennium, computers would have a billion words of memory."