Wednesday, February 12, 2014

Will SETI find E.T. WiFi by 2040?

Fusion (off-topic): In October 2013, we were told about a positive energy balance at the National Ignition Facility near San Francisco, California. Today, The New York Times and everyone else spread hype about some further advances since October. I used the term "hype" because I didn't quite understand what the advance since October is supposed to be. The overall energy budget is still poor, only 1% of the energy burned by the lasers is recovered.
The Daily Galaxy is among those who bring us the new E.T. gospel: SETI's chief astronomer Seth Shostak (*1943) promises that by his 97th birthday in 2040, SETI will find electromagnetic signals sent by the extraterrestrial non-resident aliens.

I am afraid that if he's around in 2040, people will have forgotten about his promise and if they will remember, they won't spank the poor 97-year-old man, anyway.

He builds the prophesy on the quantification of the number of planets that are being discovered and analyzed, their percentage in the habitable zone, and some amazing assumptions about the "straightforward" evolution of the intelligent life if not the technological singularity.

Stephen Wolfram agrees and adds some comments that these clever ETs produce so complex and sophisticated artificial products that they become indistinguishable from the natural objects ("very advanced cars start to resemble trees", he essentially says).

I tend to disagree with all these guesses.

First, I don't think that advanced cars will resemble trees. For quite some time, cars have been getting "smoother". Aerodynamics is one of the reasons. But even internally, carmakers don't want to flood cars (and other products) with lots of confusing details. The simplicity, at least the visual one, is one of the features that are favored by the natural selection in the world of technology.

Sometimes technology copies an idea from Nature. But we often see that animals and plants are suboptimal in many respects and when products are made from scratch, most of these seemingly useless imperfections may be avoided. So I would probably think that the converse of Wolfram's statement is much closer to the truth: the more advanced a civilization is, the more clearly its environment will differ from the natural background.

I am also ready to bet that by 2040, intelligent ET electromagnetic signals will not have been discovered. (If you wish, we may agree that the 1-to-1 bet will be active as long as both parties are alive.) Well, I just don't believe that intelligent life is that common.

Instead, I always agreed with Michael Crichton's view on these matters. He used the Drake equation as the original template for numerous kinds of the postmodern pseudoscience, including the global warming hysteria, in his speech
Aliens Cause Global Warming
that he gave at Caltech in 2003. The Drake equation includes at least seven factors – my 2005 edition of the equation contains dozens if not hundreds of factors – and all of them are mostly unknown. Some of them have huge uncertainties that may add or subtract many orders of magnitude. Even those that are only "somewhat" uncertain are so numerous that the product may be almost anything. Moreover, the product in the Drake equation is dominated by various fractions and percentages that are meant to impose a story on you.

It reminds me of a game we would play in the kindergarten. "What is pouring if you prick your finger?" – "Blood." – "What is pouring if you prick your thigh?" – "Blood." – ... – "What is the color with which you cross the road?" – "Red."

Try it. It really works. The repetitive questions at the beginning make you think about the blood. You become so brainwashed that you choose "red" instead of "green" as the answer to the pedestrian question. In a similar way, the Drake equation is deliberately containing lots of factors, some of which are arguably "large" or (in the case of the fractions) "of order one", and this makes some people brainwashed and assume that all of the factors must be large of order one. But the factors have nothing to do with each other, except that they were artificially and demagogically incorporated into an equation. One of them or several of them may be really tiny or de facto zero. Even though one factor that is tiny could be in a minority (most factors could be large), it would still decide about the result's being very small. It seems to me that people love to fool themselves with a trivial fallacy that "the majority of the factors" is what decides. It doesn't.

I think that intelligent life is rare – if not confined to the vicinity of the Earth – for many reasons.

One of them is that it may be very difficult to construct the simplest RNA/DNA molecules that may produce cells capable of reproducing the RNA/DNA code. There is no known code capable of doing such things that would contain just dozens of bases. Craig Venter's artificial cell has a million of bases in its DNA. Even Mycoplasma genitalium that is used due to its simplicity has over half a million pairs.

Also, I was sort of persuaded by the panspermial Moore's law suggesting that the life started before the Earth was created – because the extrapolation of the complexity of DNA codes seems to imply rather complex codes already 4.5 billion years ago. This belief of mine is strengthened by my realization – yes, I think it is an extremely important realization, overlooked by many – that the primitive life doesn't really need too strong gravitational fields (adhesion is OK) and the surface of a rock is enough. But the surface area is, unlike the volume or the mass of rocks, dominated by the surface of small meteoroids, comets, asteroids, if not dust in the Solar System and perhaps in the interstellar regions (smaller objects have a higher surface-to-volume ratio than the larger ones; this ratio goes like \(1/R\), of course). I think that this is probably where primitive life began billions of years before the birth of the Solar System. This primitive life just found the Earth to be a particularly hospitable place for further evolution – for concentrated progress.

Vast regions of outer space with dust and small meteoroids may have been needed to accidentally produce the smallest molecules that were needed for life to erupt. Only a small portion of the interstellar space may be "infected" by these tiny seeds of primitive life and only a small fraction of the infected regions may have the "right seeds" that may begin to flourish on the Earth. See that I am adding a structure or a story with extra factors, possibly very small factors, that were hiding behind a single factor in the Drake equation that was pretended to be large – without any evidence whatsover.

Moreover, I think that if it were really so straightforward to produce intelligent life and if it were so easy for a civilization to exponentially grow to conquer its cosmic neighborhood, and so on, we would have already seen signs of such extraterrestrial civilizations. The belief in "life is omnipresent trash" involves the belief in its nearly inevitable presence or birth on Earth-like planets; and in the subsequent exponential growth of the civilization that is nearly unlimited.

But if there were billions of planets with life in the Milky Way and if the growth of the civilization were this exponential and this unlimited, some of them would already have to become easily visible – even without the improvements in the telescope technology we will see by 2040. I feel that the belief that the ETs are not visible now but will be visible by 2040 is a belief in a "fine-tuning" of a sort. For this assumption to be true, the ET civilization must have been growing exponentially for many decades but they had to stop in time, to remain invisible to us in 2014. It is bizarre.

In other words, if one believes that the life is so easy and omnipresent, there should probably be many civilizations that are vastly more advanced than ours. But if this were the case, they would probably actively contact us before we would contact them. An advanced civilization out there – somewhere in the Milky Way – would almost certainly know about the Earth which is a rather bright "star" in the microwave spectrum. Some of these playful gay ET folks would probably send some strong signals directly to us to have some fun (even if their government preferred the "don't ask, don't tell" policy).

Well, this is of course only possible if the advanced ET civilization is at most several light decades from the Sun; the signals from more distant places couldn't have returned yet. But even among the more distant places where advanced civilizations may be living, they might know that the Earth was very promising for life – even millions of years ago. They could be sending localized signals in the direction of the promising hospitable planets and we should be already receiving lots of these signals.

In other words, if such a contact between two civilizations took place, the more advanced civilization would arguably be doing "most of the work" needed for the contact – because it's easier for it to do the work. We would be more likely to detect the more advanced civilizations than the primitive ones. That's why we should expect that they would have already "showed up" even if we remained relatively passive. In a universe full of advanced ETs, we would feel like the primitive tribes in the Pacific. They often see some signs of the more advanced nations (airplanes, International Space Station etc.). We don't see such things which indicates that we are not living in a universe flooded with advanced ET aliens.

But what really makes me upset about the "life is everywhere" paradigm is the same thing that was insulting Michael Crichton, namely that it is a religion. Or an inverse religion, if you wish. I mean a religion of scientism, scientology, or whatever these scientifically unjustified beliefs in something sold as "scientifically cool" should be called. Centuries ago, people would think that the Earth was the center of the Universe and played a special role. Copernicus and others showed that the Earth wasn't a special celestial object when it comes to the celestial motion. It largely orbits the Sun and there are many planets and stars and galaxies out there.

So some people love to "kick into the dead body of geocentrism" by trying to go to the opposite extreme. The Earth can't be the headquarters of life, either, they automatically assume. They believe that we have learned that the truth must always be the opposite thing than what the religion says. Except that these two types of "geocentrism" have a completely different status. The idea that the Earth is special as the center of the celestial bodies' orbits has been excluded; the idea that the Earth is where the Milky Way's life is concentrated is alive and kicking. There's no evidence of extraterrestrial life even though some people love to pretend otherwise. One of the claims is supported evidence, the other is not. Some people apparently want to hide this "detail" and this is just too flagrant a dishonesty in my eyes.

The idea that the life on Earth is the only intelligent life in this galaxy (or beyond) is perfectly compatible with everything we know about science. The only thing it is incompatible with is the science-inspired religion of "atheists on steroids" but that incompatibility is not a real problem of any sort.

A decade ago, I didn't quite appreciate it but now I do think that Crichton's insight that the Drake equation exhibits the same sloppy pseudoscientific thinking that has made the global hysteria possible decades later was a deep and true insight. It's the obsession with things that look like scientific equations but they are not scientific equations because they don't improve our quantitative knowledge of anything in any way; they're not even implying anything if we assume that they are "right". Equations that are meant to convey an ideology, not a useful calculation that tells us something verifiable, something that has been tested against the evidence. The Drake equation isn't science and the fact that this pseudoscientific construct has been sold by many people who were employed as scientists has loosened the expectations about the standards and it has allowed similar would-be scientists to talk about the threats for the climate posed by the CO2 and several other major preposterously unscientific idiocies. The scientific "beef" has completely evaporated from these science-inspired parts of our mass culture.

It started with the Drake equation and with the hype – helped by some of the modern media etc. – that the aliens have to be everywhere around us.


  1. If Panspermia could happen on Earth, it could happen anywhere.

  2. Panspermia is, by definition, life at generic places of the Universe i.e. mostly outside Earth! So your first paragraph makes no sense.

    The second paragraph is a hardcore conspiracy theory.

    The third paragraph lacks any logic. The Earth's averageness neither implies nor suggests that the number of places with life in the Universe exceeds one. These two statements clearly have absolutely no logical or causal relationship with one another.

  3. I'll try again.

    1) If Earth can be seeded by panspermic processes, why can't other planets be seeded as well?

    If we assume that life on Earth came from space, then I think it's fair to assume that tons and tons of planets out there are also bombarded with bacterial Eve.

    2) Not a hardcore conspiracy theory at all. I just don't buy the assumption of Hollywood that aliens would want to say hello. I don't think it's demonstrated. Maybe intelligent aliens would want to say hello, or maybe they wouldn't care about us at all. There's no evidence either way.

    3) If we're willing to consider that Earth is typical, then it follows that what occurs on Earth might occur elsewhere as well. Life emerged on Earth due to conditions on the Earth, and those conditions are probably not special. Water, carbon, starlight, etc are available all over the universe,

    For me, the strongest argument for the frequency of life is not simply that life somehow emerged on Earth, but that life seemed to have emerged instantly. The Sun is a star with a ~12 billion year shelf life, and within 1 billion years there was life around the Sun, probably earlier if we admit that it's harder and harder to find evidence for whatever life came first.

  4. Ironically and by definition, the Earth is at the exact center of the observable universe.

    One of the better arguments for panspermia (horrors males raping Gaia) is that life seems to have appeared as soon as the Earth's surface was cool enough to have liquid water.

    Crichton was an inspired writer and is deeply missed, at least by me.

  5. Some of the posible explanations why the extraterestrial life was not found but may exists:
    - we are living in a simulation
    - civilizations could adopt radio silence politics. "playful gay ET folks" would have little chance to send anything, because they would be executed. You would have to be very lucky to hear these occasional cries.
    - we have no idea where the progress will continue, perhaps at some level ET lose their curiosity, become pushing button causing instant orgasm instead of normal life and competely vapour

  6. While I tend towards your argument (3) myself, the foundation is not rock-solid. Every human is "typical" (or s/he would not be human), yet only one of them win the lottery every week. Adjust the odds downwards and there will be only one winner per year, and so on. Fermi's question ("Where are they"?) neutralizes the argument from plausibility for other planets in the galaxy harboring technological civilizations. For the time being, the working hypothesis has to be that the odds are 1-to-100-billion (est. # of planets in the Milky Way).

    For primitive lifeforms to arise on some other planets, the odds should be better. My guess is that future researchers will discover spectroscopic evidence of *some* form of life (likely nothing more complex than our algae or lichen, although we can't know until we get there) on extrasolar planets within the next twenty years. Then, the question will be how to act on this information. Set aside a big chunk of global GDP to send one-way robotic missions to explore worlds lightyears away, with success decades away in the best-case scenario?

  7. Too much theory, not enough observation. Its easy to see why our modern physicists cannot perceive the obvious.

  8. I agree that the argument is not rock-solid bt I think that the question of "is there intelligent life in the universe?" is one that is really in the suburbs of science rather than science proper. We're dealing with a lot of concepts that we don't really understand. For example, what counts as "intelligence"? Maybe that's well-defined elsewhere.

    In principle though, this can become more scientific over time, and astronomers are tackling "related" questions, for example the global statistical properties of planets, and in the next few decades, the distribution of atmospheric compositions of planets.

    I don't agree with sending robotic probes. I think that the current trajectory of astronomy, of mapping the statistical properties of planets: mass, radius, temperature, atmosphere, and eventually continents versus oceans, etc. is the right approach and much more cost-effective.

  9. I have reached a similar conclusion - which btw is upsetting to me. Things would be much more interesting if Star Trek or Star Wars was real :-)

    Anyway, I disagree with your sentence "But we often see that animals and plants are suboptimal in many respects". I submit to you that nature is practically overflowing with optimal organisms. In fact, almost everything evolution has created is several orders of magnitude (as measured in unit of IMHOs) more optimal than the corresponding artificial attempt. Now of course, trees don't make good cars, but trees were never intended to be anything other an optimal self-reproducing solar energy collector.

  10. Dear David,

    1) as I already wrote in the blog post, seeding by the pansperm may work everywhere, but in a vast majority of the Universe, the pansperm may simply be unavailable, much like string theory groups fail to exist in most towns on the Earth.

    2) you may assume that one particular civilization is a hardline totalitarian regime, unlike ours, that avoids interactions with others. But assuming that all of them or a vast majority of them *differ* from this basic feature of ours is an unnatural, unlikely assumption

    3) it's simply not true that the typicality implies omnipresence. Even if the probability of a habitable-zone planet getting life is 10^{-30}, it's still likely that the (only) planet that will win the bounty will be typical.

    Panspermia gives a different explanation why life started on the Earth right after its birth - it already existed before. It's just one example of a loophole in the SETI enthusiasts' thinking - in reality, the SETI-like thinking is literally composed of holes, loopholes, flaws, and wishful thinking.

  11. i wish we had an inventory of all the molecules to be found in galactic molecular clouds - might answer a bunch of questions about life.

  12. how strong would a signal have to be for a given distance before it's indistinguishable from the background? maybe it's not very efficient for a civilisation to keep the signal on for years...

    also...what are your thoughts on the odds of intelligent life evolving on a hospitable planet already infected with these panspermic seeds?

  13. kashyap vasavadaFeb 12, 2014, 4:34:00 PM

    Very interesting debate. Actually, I just ‘heard’ that the senate of the planet Andromede in the galaxy Andromeda passed a resolution: “We should
    tell our scientists not to waste their time and effort in trying to communicate with people of earth. They are so stupid that they cannot solve simple ST
    equations. Everyday their so called experts keep on debating about information paradox in BH and infinities of divergent series. They cannot harness simple things like thermonuclear reactions, not to mention particle-antiparticle reactors. We have nothing to gain from these idiots! We might as well try to talk to squirrels in our backyards. There is a planet in the galaxy NGC1234 which is more likely to have more advanced life. We should concentrate our resources on communicating with them. We are likely to gain something from such efforts.”

  14. Dear Lubos,
    thank you for posting the link to the nice Crichton's talk

  15. The question now is whether the probability of finding life on 1000 times more planets is higher now than when we started, conditionally on what we have observed. I don't think so, for several reasons. The main one being that we have already sampled a decent number of planets. The idea that we will find some new kind of Goldilocks condition where life can occur but did not get discovered on the planets we have checked already is very small. Then it is a matter of whether when life can occur, will it occur. Panspermia is a strong argument why it should. The alternative is that abiogenesis occurs separately on each planet that has life. Then is is a matter of whether that process is likely or not on a typical planet. It happened so quickly on Earth that it is not going to be an extremely unlikely event. We are back to the fact that we have sampled lots of planets and have not found another case of a process that we have already observed on Earth is not a low probability one, when the conditions are right. My guess is that intelligent life evolves quickly to a point where it does not care to communicate with primitive beings like us that they can understand completely just from first principles. So they have no reason to send out radio waves.

  16. Yes, such civilizations may become certain of the probable distribution of intelligent life forms in their cosmic neighborhood but simply accept it as a fact of no significance to them because no benefits would accrue from the slow bidirectional communication. In other words, “So what?”
    It also seems to me that any assumption of exponential growth is highly suspect. I can envision a future in which mankind becomes perfectly content with its life confined to a single planet.
    I do think the probability of an extraterrestrial visit by an instrumented package is much greater than a visit by alien beings but even that is very small.

  17. kashyap vasavadaFeb 12, 2014, 6:18:00 PM

    Hi Lubos: WGC is a very interesting suggestion. If you do not mind, I will ask obviously naïve questions. I always thought that even classical GR was a gauge theory. Are you saying that quantum gravity is
    different from other gauge theories? If GUT ideas are right, somehow it has to catch up with other forces at the GUT scale. Right?

  18. A very old joke:
    - Is a life possible on Mars?
    - Not even there.

  19. The SETI folks have done a good job of assessing the signal-to-noise ratios and required broadcast power. Beaming, of course, is essential.
    I agree with Lubos that the probability of primitive life evolving into intelligent life is very small but it is hard to quantify.

  20. "Answers to such questions – about parameters etc. – may only come from a complete theory."
    I may be missing the point, but surely there are parameters whose (tiny) values have to be explained at the effective theory's energy scale itself? For example, the \theta angle in QCD - can't postpone the problem to high energies, isn't it? Sorry if I'm missing the point though, I would be glad if you can sort me out.

  21. Dear Kashyap, thanks for your interest but come on...

    Gravity obviously differs from other forces in some respects, perhaps in most respects, does it not? Its messenger has spin 2, it is nonrenormalizable as a naive quantum field theory, it has no adjustable gauge group like Yang Mills theories, and so on.

    You also seem to be utterly confused about the meaning of the acronym GUT. GUT is Grand Unified Theory which never includes gravity. Unification of the nongravitational forces with gravity is only possible in string theory which goes beyond GUT.

    To summarize, gravity is surely different in many respects. If it were the same as electromagnetism, we would not be using another word, would we?

    Sorry that I cannot resist to point out that your question is really stupid.

  22. kashyap vasavadaFeb 12, 2014, 7:35:00 PM

    Sorry. I should have said "some unified theory including gravity" instead of GUT. I see your point. Gravity has no adjustable gauge group like Yang Mills theories. That must be the problem.

  23. The unlikeliness of intelligent extraterrestrial life is suggested by the rarety of intelligent terrestrial life. Notwithstanding reports of octopi deducing how to escape from containers, bored monkeys flinging their feces at zoo visitors, and the opinion of the late television comedian Johnny Carson that pigs are smarter than horses, only one out of the millions of species on earth has been able to come up even with the notion that a pair of numbers--one of them denoted by an 'i'--might be of some use in the scheme of thing . . . and that took them eons. Moreover, most members of this intelligent species are croutons who contribute very little to the so-called ascent of man here on a planet teeming with life. So what hope for outer space? Of course, intelligence is a plastic word: one might argue that dolphins and whales are smart enough not to have deployed genocide or torture as a feature. Mosses and lichens don't write concerti but they don't have traffic jams or reality TV either...

  24. Lubos, I'm glad to see you used the word "scientism" as having negative connotations, which is the way I like to use it. We need a word to designate ideas that try to look "sciency" with a lot of mathematical equations, etc. but actually are not. Pseudo-science does that admittedly but it is too long and covers things like Marxism and Freudianism, which did not use mathematical symbold. Modern mathematical economics, most of it, is my idea of scientism in action today, though you probably disagree.

  25. "It's the obsession with things that look like scientific equations ..."
    Lumo, read the book by Premysl Rut: "Namesicny pruvodce Prahou", or at least the story "Restaurace u Jeziska" from that book. You will like it.

    As for "the hype – helped by some of the modern media etc. – that the aliens have to be everywhere around us.". Have you ever seen Dennis Rodman? I rest my case. ;-)

  26. Dear Lubos,
    I don't quite get it. Yes the chance to receive signals from aliens may be low for various reasons etc. But the fact is no one really know. So not to try to look for those aliens with the technical possibilities one has and with comparatively modest financial effort seems to demand an unusual absence of curiosity especially for a scientist.

  27. Oh man Lubos, that 2005 article of yours is a classic!

    Hm, thinking about it, it's a pretty simple observation to make, but one with profound implications, that the longer the chain of assumptions, even if those assumptions are individually of high probability, necessary for a particular conclusion, the more improbable it has to be-as a simple consequence of the way probability works.

    And that the universe is filled with aliens or that global warming will kill us all, are things that rest on long chains of assumptions, each of which is individually of at best moderate probability. The end result is that the claims actually have vanishingly small probabilities.

    And yet people believe them anyway. Truly faith-regardless of in what-is a powerful thing. And in the case of climate alarm, quite dangerous.

  28. kashyap vasavadaFeb 13, 2014, 2:51:00 AM

    @Werdna: Small probability for an event does not mean that it will not happen. After all no of possible events= its Probability X total no of systems. Lot of people argue that arising of life on earth is such an extremely low probability event. But it did come up. Didn't it? As another example what is the probability that I meet a person from my country of origin (with a billion people) here in U.S. Very small, but I run into them all the time!!! I am not really arguing one way or the other, but suggesting that either conclusion is possible.

  29. Hi Lubos. Brilliant analysis. I tend to agree with your views on self-reproducing matter. And the LIE hypothesis really has got religious over- and undertones.
    Now to your kindergarten experiences. Maybe the answer "red" to the zebra stripes question isn't so wayward after all. If you cross the road on RED, red matter will possibly pour out of the entire you and you'll be past history soaked in red. ;-)
    LIE hypothesis=Life Is Everywhere hypothesis

  30. Yes, expected number of occurrences is n*p where p is the probability and n is the number of "trials" so if n is very, very large, n*p should not be.

    The universe is big, so n*p is probably at least one in the case of expected number of times intelligent life arises somewhere. On the other hand, p is so small that even if n*p is greater than 1, the others are very far away and we'll never hear from them indeed.

    In my opinion, n*p in that case is probably a small number on cosmic scales. My sense is that SETI types have no sense of how large that number would have to be for the fact that it is greater than 1 to actually matter.

    On the other hand, in the case of climate alarm, n = 1, so n*p = p, which is a number significantly less than one, and represents the number of futures in which we can expect to all be dead from global warming.

    We can combine the two, though, into a kind of funny scenario: the expected number of times intelligent life somewhere in the universe is wiped out by their own global warming, n*p*p. I would actually be surprised if this number was greater than 1, which I suppose gives you a sense of the relative scales I place these probabilities on.

  31. SETI, the grand snipe Hunt!

    First assume “they” exist. Then assume the possibility of detecting them sans knowledge of one scintilla of how “they” achieved galactic communications. Assume we gain nothing.

    A better approach is to advance science to the level some believe “they” have already achieved and we will be the first to make contact IF “they” exist. If not, we still have something for our efforts.

    Or we listen and wait.

  32. Dear Mikael, I have never suggested the cancellation of SETI. The costs are indeed negligible and the "chance" to contact them may justify them.

    I am just saying that it is not science. Just someone's being curious about aliens doesn't make his reasoning scientific. The idea we're on the edge of contacting them isn't science. The wishful thinking that we know how to do it is not science. Promises that the contact will take place before 2040 (ludicrously accurate deadline, by the way) is not science.

    The attempts to suppress the skeptical possible answer by demagogy is unscientific and just plain unfair.

  33. Dear imho, maybe they will visit in some future. But you should understand that sci-fi movies are still pretty compressed and they often describe more than what may happen in one lifetime.

    I don't believe that the organisms around us are optimal in *any* respect. All of them are done so that they barely work. Humans are physically very mediocre ones, by the way, too. No animal was even given a wheel - such a trivial technological feat. The thermal losses of energy are huge. The resolution and sensitivity of the eyes is poor. The strength of the hands and legs is low. We catch infectious diseases more often than Windows PCs catch viruses. And so on and so on.

    It's great that those organs and organisms evolved "naturally" but that's no reason to praise them with superlatives that are untrue. Engineering is ahead of Nature in many many things already.

  34. LOL, not sure whether this is serious or not.

    There's no "observation" suggesting any positive answer about extraterrestrial aliens whatever.

    Whether we live in the Matrix is an entirely different topic. There are lots of reasons to think that the answer is No but I won't go into it here.

  35. Right. There are about 500 other things that could go "wrong", too.

  36. There's another reason that we won't find the alien radio signals: the most efficient use of radio for transmitting information uses modulation that is indistinguishable from natural noise. Shannon is hard to fool for long.

    When SETI started, radio on earth had been using low efficiency (low bps/Hz) transmission for about 70 years, with great big zero-information content sinusoidal carriers. In the last 20 years, we have moved most of that to high bps/Hz signals - noise-like signals.

  37. Right on spot. You know, there's something about SETI that makes some people go completely nuts. I'm thinking about Judy Foster. She got so worked up by her role as a female "scientist" in that SETI movie that she deluded herself into believing that she could transfer her actress SETI prowess into real life competence. She became a self-appointed arm-chair scientist! She and many of her Hollywood (alarmist) ilk reminds us that SITI isn't over yet for some selected regions, like the Hollywood film sets.
    SITI=Search for Intraterrestrial Intelligence

  38. I think there are reasons to doubt the idea that space aliens might be so very far ahead of us that they wouldn't be interested in communicating. It assumes:

    1. that it is possible be enormously more intelliigent than a high-IQ human being;

    2. that we are enormously far from being in a position to understand whatever the aliens would know which we do not know.

  39. Absolutely not. Not even close.

    First, lets start with the obviously incorrect statement that the wheel represents optimal engineering. A wheel, which requires manufactured lubricant and a high degree of symmetry (hope the wheeled species is never injured lest the wheel becomes an oval), is completely and utterly impractical for any organism that needs to move quickly over rough terrain, climb trees, move up and down hills, etc. Not the mention the total inability to move laterally which in critical to staying alive. Go hunting in the forest with your bicycle and wrestle a deer while still riding... let me know how that works out for you. Sure, the wheel is great if you want to transfer 10 tons over friendly terrain... but that is solving a completely different engineering problem than the leg solved.

    The human body is tuned precisely to survive on minimal energy (for 50 or more decades) in hostile. constantly changing environments, while self replicating with only the resources found in the immediate vicinity. Why would one engineer stronger hands and legs, when instead one could engineer intelligence which gives the ability to use weapons and tools. One would fail a freshman engineering class with that solution. For what engineering purpose would the eye need to be as strong as the Hubble. The eye needs to function for 50 years with no maintenance while identifying food, threats, and mates at a range of 1 - 100 meters... for those purposes it's absolutely flawless!

    Your comparing apples and oranges.

  40. LOL, you clearly *define" optimality to be whatever you see in Nature. Everyone who adopts a more objective, less vacuous definition will see that you are wrong.

    The simplest way to see that your tirade against the wheel is just a propaganda prepared to defend a preconceived conclusion is to show you that you're actually utterly wrong - Nature does use the wheel concept in living systems, too. See

    It just wasn't able to scale it.

    I am amazed that someone would be trying to question that wheels are a better way to move. Just compare how far and how quickly you may get with a bike vs walking.

    You're a ludicrous Luddite if you have to attack a human invention just because you don't see it in Nature, especially if you don't see it just because you're not looking carefully enough.

  41. Brilliant Lubos, I love this chunk:

    "It's the obsession with things that look like scientific equations but they are not scientific equations because they don't improve our quantitative knowledge of anything in any way; they're not even implying anything if we assume that they are `right´. Equations that are meant to convey an ideology, not a useful calculation that tells us something verifiable, something that has been tested against the evidence."

    And it's got a name: Physics envy. It's a powerful concept, and explain some features of social sciences, or more generally, of pseudosciences.

  42. No... I'm pretty sure my argument will stand on it's own to anyone with half a brain. We are now at the point where you're own "winning exchange" contradicts your earlier arguments and proves my point.

    Yes you are correct that nature is indeed engineering organisms "to survive" that is the merit function that nature is optimizing and in that respect nature is flawless. In what bizarro world do we judge nature based on how well it minimizes a merit function it never intended to minimize???

    You are also correct that modern engineering based on optimizing very specific and small constituent mechanical parts whose purpose is to perform (usually) one single function, with constant maintenance and human intervention. In that respect, a wheel on a concrete, well maintained road is superior to a leg. But I'm not sure what that has to do with this exchange?

    Let me ask you this Lubos. Why does the mars rover team look for the smoothest terrain possible? It's because 90% of the possible terrain is completely unsuitable for wheels. So why does NASA not build a robot with legs and arms that can scale mountains, climb into pits and traverse deserts... It's because we lack the technology skill and sophistication...nature is simply better.

    This is undisputable fact.

    BTW here's an improvement on your slow car / iphone analogy. It's more like you're calling cars suboptimal because they don't have state of the art Bose sound systems. I'm explaining to you that cars don't need start of the art Bose sound systems and moreover, improving the stock stereo system is senseless when would could simple install an iphone port for itunes.

    Thanks for the link, and yes... nature stopped using gears because they don't scale and are generally a stupid idea for multipurpose, robust organisms.

  43. Dear imho, to answer your question: we started this conversation-which-is-a-waste-of-time because you began to assertively defend the creationist myth that organisms are perfect or flawless or perfectly optimized, and I explained to you why you were deluded.

    Your attack on the rovers and their wheels is particularly stupid because wheels have actually made it to Mars why legs haven't, so wheels are clearly superior in this discipline as well, aren't they?

    People have mastered machines with great legs - superior to human legs - as well. See e.g. the Boston Dynamics video - firm currently bought by Google:

    Such things haven't been used by NASA because they were not sufficiently tested at that time and because this complex system may suffer from the same disadvantages as biological legs. So I would predict that most of the machines to move on celestial bodies in the next 20 years will still use wheels but even if they use mechanical legs, they will be legs created by engineering, not leg know-how directly copied from Nature.

  44. “an effective field theory is only good at describing the effective phenomena, and it shouldn't be trusted when it comes to global questions such as "where it must break down"

    Fermi’s theory is a very nice counterexample to that. Isn’t it?

  45. I didn't mean it this far. Of course, an effective theory has to break at the cutoff (or earlier). But the point is that it may cease to be valid much earlier than that, and some regions of its parameter space may be OK theoretically but still physically irrelevant for reasons that are only visible outside the effective field theory.

  46. This is unrelated, but I'm wondering about your thoughts on 1311.0239 -- accepted for PRL recently.

  47. LOL, it could be an interesting calculation if firewalls could exist. Unfortunately, it is not the case.