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Galaxies can't be overrun by bored, suicidal extraterrestrials

Petigura, Howard, and Marcy published a paper in PNAS attempting to count the extraterrestrial civilizations:

Prevalence of Earth-size planets orbiting Sun-like stars
Whopping 22% of Sun-like stars are said to have Earth-sized planets in habitable zones. So the environment is as perfect as here on Earth almost everywhere. It's not only untrue that "there is no Planet B". In fact, there should be billions of hospitable planets in the Milky Way and the closest culture should be less than 12 light years away. But we haven't heard from any ETs yet.



Fermi therefore asked the question "Where are they?" and the question may look even more pressing today than it was decades ago. In "Billions of Worlds", Sean Carroll proposes an explanation. We don't observe any visible civilizations at the galactic scale because they get bored and stop any growth before they reach this level of influence.

This explanation is known as EBH which stands for "Environmentalism Busts Happiness". We are speculating about the psychology of different creatures – or humans/creatures on Earth in a very distant future – but we may still speculate. Is EBH a viable theory? Well, I don't think so.




Some readers on Carroll's blog raised important objections to the EBH way of thinking. Joe Bloggs wrote:
While fun to think about, the EBH seems impossible as defined! What definition of boredom results in inaction? Whether we’re talking about restlessness or existential ennui, boredom is a problem to be solved. It is the unique trait that _triggers_ creativity and exploration.
Indeed, it is very problematic to identify "boredom" with "inaction". People are doing – and have been doing – many new and unconventional things exactly because they were bored by everything else. So the sentiment needed for EBH to work isn't really "boredom" but some kind of self-effacement or material modesty, something that actually curbs expansionism and supports inaction.




Fine, so do these sentiments win as the civilizations get more advanced? Are more advanced intelligent beings inevitably closer to monks? Maybe, you could think if you had a look at modern monks such as your humble correspondent. However, Greg has pointed out an important oversimplification in this line of reasoning:
Suppose most members of most intelligent species eventually get bored of life. Those members will die out, or at least fail to conquer the galaxy, leaving only those individuals who aren’t bored of life. So there is natural selection in favor of not getting bored, which makes the EBH unlikely in my view.
In other words, it doesn't really matter how bored or modest or passive the average intelligent beings become. Despite Sean Carroll's obsession with mediocrity as the golden standard for everything, they are not those who will dictate the overall character of expansionism of their civilization. It's enough if some intelligent beings want to expand, want to compete, want to be richer and more powerful than ever before. Those – and perhaps their disciples or offspring – will determine what the visibility of their mother planet etc. will look like.

This observation is nothing else than Darwin's natural selection and there's no good reason why it should break down at a particular scale – even though we're trying to extrapolate to ridiculously distant moments in the future. One reason why it seems implausible that the "desire to grow and expand" will completely disappear is that it could have happened a long time ago but it didn't.
MSIE 11: Off-topic: fans of Microsoft Internet Explorer should download MSIE 11 (64-bit or other languages) which is faster and supports more modern standards (and is personified by an Aryan Japanese clumsy anime girl). In a few weeks, it will be automatically pushed through the Windows update service. There is a tool that forbids the updates, too.
Soon after the bacterial life was born, they could occupy much of the planet and they could think that the "mission was accomplished". But they didn't. They kept on evolving. OK, let me skip many similar steps and jump straight to humans who actually use their brains to think. Well, some of them and occasionally. Centuries ago, humans were able to feed themselves and they could become bored and stop any progress. They didn't. They found important theories of physics – Isaac Newton's theories, physics at the end of the 19th century – that made them believe that they almost had the theory of everything. That could lead them to stop expanding and terminate the progress. It didn't. And so on. In fact, the ability to do and understand certain things invites many other people to apply them. Key breakthroughs in science may turn their finders to modern monks but they have the opposite effect on the rest of the society. The society is looking how to benefit from anything and everything.

We may actually be facing some threats resembling EBH today. The Luddites – most of whom have largely adopted a new trademark, the "environmentalists" (and the "global warmists" represent the most aggressive branch of this movement so far) – are trying to curb the economic growth and especially the "extensive expansion" of the mankind and its influence. Does it mean that they will make the progress stop? Is this cancer of "environmentalism" what stops almost every extraterrestrial civilization and prevents it from becoming visible from the Earth?

I don't think so. The environmentalists and similar -ists are annoying and may look like a threat for the human progress. The society seems to tolerate them. But it's only because they haven't really made any \(O(1)\) impact on the life on the Earth. They're just a minor gang of parasites and demagogues. If they actually started to threaten 50% of people's wealth and income, ruin 50% of their dreams and 50% of their freedom, I am confident that a violent backlash would erupt. A sufficient number of the environmentalists would be physically eliminated so that the movement would disappear.

Soon or later, such liberation is bound to happen in regimes that restrict the human freedom. The bad news for you is that the process may be too slow and most of your life may be affected. The good news is that dreams about 1,000-year-long totalitarian, stagnating empires can't work. Even if such socialist or environmentalist empires manage to defeat their external enemies, they're not protected against internal developments. The smaller the external threats and foes become, the more the people focus on internal struggles. The stronger bodyguards you hire to protect yourself from external freedom warriors, the more you risk that you will be assassinated and stopped by your own bodyguard. This ultimately leads to the restoration of the diversity and the revival of the natural selection and progress, too.

No doubts about it, environmentalism is a major example of a disease that may cripple whole societies and stop their progress. But it can't do the same thing with all the life on Earth. The societies suffering from similar diseases may slowly die or become irrelevant but others continue to expand and make further progress. It can't be otherwise.

The most likely interpretation of the absence of extraterrestrial signals is still the obvious thing: There are simply not too many extraterrestrial civilizations if there are any at all.

The number of nice enough planets in the habitable zones may be very large and life may start to spread all over the planet soon after the seed of life is created there or gets there (this speed is what our geological records indicate) or but it's not necessarily the case that the "seed of life" appears on all habitable planets.

In recent years (which is relatively recently), my belief was increasing that the early life was actually born outside Earth. See Amino acids born on an artificial comet and especially Panspermia follows from Moore's law. In the latter article, I already coined the concept of "increasing concentration of sophisticated genetic or industrial capital" as an explanation of many patterns and hierarchies here.

Let me add a few words.

Protons and neutrons are "pretty much everywhere" in the Universe. More complicated atoms are "almost everywhere". Simple molecules appear at some special places, simple organic molecules in an even smaller fraction of the Universe. Now, life-creating minimal organic molecules may only be present on comets in various clouds of hope, in a small percentage of the galaxies. 4.7 billion years ago, one such cloud could have surrounded the newborn Earth and the early primitive organisms may have found the Earth to be a great place to expand and evolve.

Only the most fertile places saw the growth of the human civilizations 6,000 years ago. A small portion of the world today is covered by prosperous economies. I could continue with this ever increasing concentration. At the end, we could mention that the top string theorists only occupy a few hundred cubic meters somewhere in the physics departments at Princeton, NJ and in Cambridge, MA. Apologies to the Holy Father and others who may have expected that I would identify a different tip of the pyramid of intelligent life. ;-)

Note that this increasing concentration actually does solve the Fermi paradox. It is not enough for a planet to be Earth-like and to belong to a hospitable zone for the planet to host life. Why? The sequence above offers us many analogies. One analogy is: It is not enough for a physics department to have a staircase similar to Harvard's staircases if you want the department to contain the world's best string theorists. ;-)

The very early, extraterrestrial life didn't need conditions that were too luxurious; it didn't really need the Earth. (I hope that this claim may be supported by independent arguments based on the analysis of how this life worked.) The surface of comets – with a negligible gravity etc. – was enough for these creatures that were satisfied with the surface tension instead of gravity. Such an early life could have ignored the separation between planets and zones. It depended on lots of surface of solids and cosmic dusts or comets may have dominated in this discipline (even though they have a smaller volume or mass than the planets – most of the mass of planets is "inside the solid" and therefore not helpful for life).

The dust that was containing seeds of life wasn't covering the whole Universe 4.7 billion years ago. It only occupied some clouds and stellar neighborhoods. The stars with such seeds in their vicinity could have been as special as the string theory departments are special among the academic buildings today. But this could have been just the initial condition in the evolution towards even higher concentration.

My main points are that the increasingly sophisticated structures and life are increasingly rare and increasingly concentrated to special places; and that the first forms of life on Earth weren't really at the very beginning of the evolution of life so they were already somewhat concentrated to some places in the Universe. Such a general big picture may also be seen to imply that the planets with life are rare and extraordinarily powerful civilizations are even rarer.

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reader Frigidaire said...

I don't think adding another factor like this is necessary for explaining why powerful civilizations are rare or why we haven't found life. The billions of years of life on Earth before complex macroscopic creatures suggests that the transition to multi-celled organisms must be difficult and rare. There very well may be life on some of these planets but we don't have the capacity yet to get a closer look. As for advanced civilizations, after reading E.O. Wilson's The Social Conquest of Earth, I'm convinced that highly intelligent life requires eusociality which is very rare among animals. The emergence of humans was not at all inevitable. Eusociality also suggests that any intelligent life is going to have the same in-group/out-group problems we do, so they will also face the threat of destroying themselves with nuclear weapons if they get to that stage.


This reasoning makes seems more plausible to me than positing that the organic compounds necessary for life are only found in comets which are not evenly distributed. My suspicion is that life is common, large organisms are rare, intelligent life even rarer (we're probably the only ones or part of a handful).


reader anna v said...

This argument will also work to dismiss the Boltzmann brain basis of your previous blog entry, imo.


reader anony said...

I think one has to also account for the extreme unlikeliness of the discovery of modern quantum theory, which by direct measurement, only has a probability of discovery of around 1 in 2 billion of a sufficiently mature species, combined with the active development of the printing press at around 1 in 100 million, and the development of written language at around 1 in 10 million, we get to a simplified estimate that a sufficiently intelligent species only has a probability of 1x10-23 or 1x10-24 that they will have the ability to communicate via radio with any other species.


reader Luboš Motl said...

Hi, well, the unicellular vs multicellular or microscopic vs macroscopic "gap" may look like a large one because it's easily understood but I think it's a really tiny step - as all yeast sufferers know, for example. It's a tiny step, a tiny change in the behavior that makes cells organize themselves into multicellular objects.


There are many "less easily understood" but probably much harder steps that Nature had to do before it reached viable unicellular organisms. Quite generally, the evolution was composed of a large number of steps and the more details one understands about these matters, the more he knows that each step was a relatively doable step among many.


reader anony said...

Point being, it is extremely probable that even if we are not alone, we are the most technically advanced species in our galaxy if not the universe


reader Luboš Motl said...

I sort of see your point but isn't it working in the opposite way?


All the discussion about "increasing concentration" was talking about things that evolved "regularly" from a common root of being. The Boltzmann brains are about avoiding this standard tree of being altogether. So while it's true that increasingly real-world-like Boltzmann brains and Boltzmann environments are increasingly rare, their number may still be infinite.


reader Luboš Motl said...

OK, I don't believe these tiny probabilities. It seems almost inevitable to me that a species that discovers Newton's equations will also master quantum mechanics in a timescale short relatively to the astronomic or cosmological timescales.


reader anony said...

The justification for the tiny probabilities is that if we accept that individuals in a species have roughly the same amount of computational ability, and one treats key discoveries as either independent or weakly covariant, then as the mind explores the space of meaningful strings, we should be able to look towards the rough accumulated population at the time of discovery to estimate the probability of discovery for any advancement. The real hard part is the estimate of covariance between discoveries. Granted that would drive the probabilities down, and maybe into the threshold that you might think is more reasonable. I just think that we have to treat the formulation of ideas that lead to advancements as events, and not as smooth extensions of a function


reader Frigidaire said...

I dont see this as left-wing propaganda, and I'm not sure where you got something like that. Anyways, I think you may be mistaken that there is nothing evolutionarily complex about eusociality. From my understand of Wilson's argument, eusociality requires a distinct evolutionary sequence that is overall very unlikely to occur. Eusociality only occurs among ants, termites, bees, humans, and a few other species. That kind of eusociality is rare and has only occurred a few times independently over the course of evolution. Eusociality in a species physically capable of having large brains has only occurred once.


I don't identify eusociliaty with the "best progress of life." Just saying it is very likely a necessary, and rare, step for the development of very high intelligence, which adds another "filter" for how many advanced civilizations we can expect to see. I think it is more plausible that the rarity of eusociality in species capable of having large brains can explain the lack of E.T. than positing unequal distributions of organic chemicals in comets.


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reader Luboš Motl said...

It's not clear to me whether you hear yourself, whether you know what you're writing.

You're presenting "eusociality" as something rare and precious, yet you enumerate a half-dozen of very distinct examples of random insects and mammals. You could have added several types of mole rats. Readers may be biased about humans but if we look at the remaining ones, termites and rats of various sort, I don't think that they belong to the "elite" of the creation.


Also, the very existence of multicellular organisms is an example of eusociality, cooperation between the cells. There's nothing rare about this mode of behavior, there's nothing difficult for Nature to develop it.


reader Andrew Gordon said...

Once a species realizes that the universe will eventually end, and time with it. There is the inevitable conclusion that after the universe ends then it never even happened. But I am an optimist and agree with the writer :)


reader Pavel said...

Isn't Islam much worse threat for civilization than environmentalism? In all places on our planet, where Islam took power, the civilization progress not only stopped, but it were reverted several centuries back. And no restoration of progress is seen in such places.


reader Luboš Motl said...

LOL but a problem with the comment is that the Universe will not end. It will approach the empty de Sitter space that lasts indefinitely. In some sense, we're already close to an empty de Sitter space - most of the energy density is already the cosmological constant, like in de Sitter space.


reader Luboš Motl said...

Maybe. I don't believe that the Islam may conquer the world. The tolerance towards its penetration is only high because it isn't making a real impact yet and the people prefer to look tolerant.


However, if the threat that it overruns a Western country became real, the tolerance would evaporate. Even in threatened countries like France, one may see that 10% of the Muslims translates into 20% of the supporters of anti-immigration parties. That yields a simple calculation to believe that the first figure can't surpass 50%.


reader Kimmo Rouvari said...

"The most likely interpretation of the absence of extraterrestrial signals is still the obvious thing: There are simply not too many extraterrestrial civilizations if there are any at all."


I agree totally.


Maybe within a few billion years we receive something from "aliens". Another thing is does our planet survive that long...


reader anna v said...

Well, it seems to me that thermodynamics is not the way to go to DNA and brains anyway. It is quantum mechanics, and that leads to rarer and rarer processes.

The wiki article says for the Boltzman brain ( heard of it today first time here) :


"The paradox states that if one considers the probability of our current situation as self-aware entities embedded in an organized environment, versus the probability of stand-alone self-aware entities existing in a featureless thermodynamic "soup", then the latter should be vastly more probable than the former if both scenarios are to be created out of
random fluctuations."


Well it is a quantized soup full of features and some very rare like the DNA quantized state.


Anyhow the whole BB is a classical fantasy. It is as if we could have a Theory of Everything coming out from a thermodynamic soup of theories.


reader Andrew Gordon said...

Haha. I could be wrong as I am quite uneducated on de Sitter space, but would it not be at absolute zero? If so without molecular movement, does time exist?


reader Luboš Motl said...

Dear Andrew, the asymptotic temperature of the de Sitter space - our Universe in the future - is tiny but it is not zero. It is so small that the thermal wavelength (the typical wavelength of the thermal photons) is a particular number comparable to the curvature radius of the Universe.


Whether time exists in an empty space is a philosophical question. But the time may still be way too real and some isolated pockets of civilization may be preserved for a very long time - when the space is really almost empty.


Note that it only takes 11 billion years for the linear distances between galaxies to double (exponential growth) i.e. for the density of normal and dark matter to drop 8 times. So after trillions of years, everything will be really empty. On the other hand, one may arguably produce pockets of resources that allow a small civilization to survive for trillions of years. Perhaps some artificially prepared sequence of 100s of stars that will be burned when the previous one burns out.


reader Andrew Gordon said...

Wow. You sir are a very intelligent person.


reader Eugene S said...

What you're forgetting is that while history textbooks in school usually name only one person for every important discovery or invention, often there have been more than one at the same time or near-simultaneous. And once the invention or discovery becomes sufficiently well-known, others who were on the verge of the same breakthrough abandoned their efforts. Hence all your estimates of the likelihood of inventing modern language and the printing press as well as the likelihood of discovering QM are severely flawed. And as you poiint out, they cannot be viewed as independent of each other, either.


reader Werdna said...

"The most likely interpretation of the absence of extraterrestrial signals is still the obvious thing: There are simply not too many extraterrestrial civilizations if there are any at all."


Isn't an equally valid interpretation that interstellar travel is simply impractical no matter how advanced your civilization gets?


reader Luboš Motl said...

Dear Werdna, I think it's not just traveling ETs that are apparently excluded by the ET searches. It's just plain ETs who live on their planet, too.


Our Earth looks like a somewhat bright star in the microwave spectrum. There doesn't seem to be any sufficiently nearby planet of a similar kind.


reader kashyap vasavada said...

@Shanon Well! I repeat, we do not try to communicate with ants and squirrels! We have seen them but we know they have nothing to offer to us. Just think how much science has advanced in few hundred years. We cannot even imagine what advancements can take place in a million or billion years.


reader Shannon said...

Well it depends what you mean by "communicate". We do communicate with ants and squirrels by acknowledging what we see and try to understand the way they live etc. and they see us too, or feel our presence. This is a kind of communication, isn't it ?


reader kashyap vasavada said...

@Shannon. OK. That is interesting thought. But do we know what ants and squirrels think about us, if they think at all. Domesticated animals like cats and dogs are more aware of us, but even for them it is difficult to find what they think. Main difference between these animals and us vs we and advanced aliens is that these animals see us whereas we cannot see aliens (at this time) far away even if they are around. In any case, this may be a way out of Fermi paradox without using EBH. Based on probabilities, I would not bet one cent on nonexistence of advanced alien civilization.


reader Eugene S said...

Shannon!! Awesome new avatar, where did you find it?


reader Uncle Al said...

Pond scum is everywhere but technological civilization is rare. Civilizations succumb to religion (Rapa Nui, Medieval Europe), overpopulation, snit (royal houses of Europe and WWI, US government), socialism, boredom (the Great Depression)... Remove Earth's oversized close moon and its rotation axis wanders (Mars). Remove its magnetic field and its atmospheric volatiles are scoured by solar wind (Venus). Earth is an outlier.

Great civilizations arise from surplus (ancient Greece, Persia), technological carnivory (ancient Rome), capitalism (the US), and great thoughts fed then amplified by all three. If it begins with "al," ancient Islam probably did it (later trading faith for comfort). Select for intelligence by applying the lash and offering small escape apertures. 30% of Nobel Laureates are Jewish, being challenged by US university admissions-bludgeoned Asians .

Suppose ancient Greece had taken the last tiny step to calculus and differential equations, Christianity hadn't stolen 1000 years of progress, ancient China had optical glass. Suppose gene-gineering is banned. Suppose Iran and Israel have it out, thermonuclear big time. Suppose polio and smallpox tread the Earth again.


reader papertiger0 said...

A had a camera that was killed dead by my computer. Something weird happened to the camera, which was jacked into the computer, while I logged on to the net.


Never had a problem where the camera did in the computer.


For comparison purposes, I grogged that Lubos was gilding the lilly when he started on about micro-blinking, but I should have caught on when he said it could be transmitted by sound.


reader anony said...

All arguments that support my point,


reader Eugene S said...

Sorry but I have no idea what you mean. You derived the probability of a modern high-tech civilization incorporating advances in science incl. quantum mechanics by multiplying three inventions or discoveries seemingly chosen at random, to obtain an ultra-low result (1x10^-23 or 1x10^-24), concluding from this that a cilivilization like ours must be exceedingly rare in the universe.

But why these three: development of written language, development of printing press, discovery of modern quantum theory -- and why the probabilities of between 1 in 10 million and 1 in 2 billion? Did you take estimates of human population at each of these points in time and decide because someone was first and that person was one, hence the probability was 1 divided by global population? Seriously?


And why not any number of other discoveries and inventions, from a²+b²=c² to Maxwell's electrodynamic equations and from blackpowder to the railroad etc.? If all the essential links in the chain could be enumerated and the likelihood of each (according to your scheme) multilplied with every other, you'd get a probability of ~ 1x10 to the power of minus googol -- at least.


But it's completely absurd, if you will forgive me for being so blunt. Every invention and every discovery took effort and was an achievement worthy of praise. But if all the greats from Pythagoras and Gutenberg to Planck, Einstein, Bohr and Heisenberg had never lived, others would have done what they did. A little later, surely, and a bit differently.


I cannot see how an investigation into the "Fermi question" could possibly benefit from what you have offered here,.


reader Werdna said...

So we should be able to at least detect them on their planets, but we don't.

I guess intelligent life pretty much has to be very rare-it's just an inescapable conclusion from what we know.

On the plus side maybe my conclusion (based on a weaker version of the paradox) was too strong, perhaps interstellar travel *will* be feasible and we won't die with our star after all.


reader lukelea said...

There is also the issue of lifespan. Not too many adventurous types would want to take a car trip if they couldn't get back home in their life time. Even if you average half the speed of light, a voyage to the nearest inhabitable planet (assuming it is 12 light years away) risks a serious case of cabin fever.


reader Nathan Cook said...

The 'Garden Earth' hypothesis looks quite nice to me (Star Trek fans may recognize it as the Prime Directive). It goes as follows: whichever civilization first expanded into the Milky Way had such a long head-start over the others that it has been able to enforce the isolation of more junior civilizations, presumably until they gain interstellar capability.


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reader papertiger0 said...

Are we sending an intergalactic howdie? It's my understanding that we don't send calls out to the great beyond.

You can't expect to get mail without writing some letters.


What if our neighbors are sitting on their hands, tenticles, flippers, waiting on mail before they write?


reader Eugene S said...

Thanks to time dilation, travel time for the explorers should be manageable (months? a few years? the relevant equations can be found on wikipedia), while for the earthlings left behind, 48 years round-trip travel time will pass. (Different frame of reference, yuk yuk). The trick will be finding the energy to go so fast... and the technology to handle it.


reader anony said...

You are missing the underlying point, I just picked three items at random, if you want to pick three others feel free. If you want to prove to me that there is absolute correlation between radios and writing, be my guest, but if you are unable to make that connection them you have to look at these things probabilistically. Quantum as a word simple means discrete, although people coopt that definition with much more meaning, so if you want to be a grammarian be my guest. I stand by my comments because as you pointed out I mentioned that covariance can drive the mutual probabilities smaller. If you still can't understand that finding a radio on et's home world is as likely as finding them to be anatomically correct humans, then this conversation is rather pointless. I would further highlight that some complex technologies have been naturally developed and different species have used these things unwittingly for a long time, some animals have a natural sense of magnetic field lines for instance, so it's not unreasonable to think that probabilities of radio and written language are independent. I think you are again making the mistake of associating our specific evolution with other paths on other planets, this is fallacy, and I am surprised to get so much resistance on this point


reader Eugene S said...

Well, I agree that further discussion would be pointless, as I find your use of language very sloppy.



"Quantum" is not a synonym to be used interchangeably with "discrete", it refers to a well-defined conception of how nature is discrete at the fundamental level, in a clearly defined way. That conception did not exist before the work of Planck and Einstein. "Technology" is not the preserve of humans alone (for example, a chimpanzee might wield a stick to extract termites from their home) but a faculty such as the ability to sense magnetic fields cannot be called a technology by any stretch.


Oh, and insisting that words be used correctly does not make me a "grammarian". A grammarian is someone who alternates descriptive and prescriptive approaches to people' use of grammar, not vocabulary.


reader anony said...

I am actually rather glad you find such things to appear sloppy, because it reveals a weakness in your own reasoning on these matters, much like those who are suddenly surprised when the world doesn't work the way they expect.


If you want to get into the difference between grammar and vocabulary, you have to remember that there is nothing really preventing us to define words as we choose, this is part of the evolution of linguistics, if you do not understand the definitions I have chosen to use, then rules of construction of statements do in fact appear different and the discussion does become one about grammar.



And another point, looking at accumulated population as a means for understanding probabilities shouldn't be foreign to anyone in physics. All probabilities in particle physics are essentially determined by looking at the occurrence of events with respect to accumulated luminosity. Counting the frequency of ideas within some set of some accumulated human population is no different in concept, if you add some sort of accumulated knowledge threshold, you find a perfectly naturally explanation for why groups of people studying similar problems start having similar ideas simultaneously. There are all sort of rabbit holes one can go down, but when similar people are looking at the same set of facts, it is relatively easy to understand that people will begin to make connections between those facts in way that can be only understood statistically. Again, I suspect that the truth of these observations and statements are getting caught up because people secretly want ET to exist and look a lot like themselves, much like the reason your having difficulty with basic concepts in this conversation.


reader anony said...

I am actually rather glad you find such things to appear sloppy, because it reveals a weakness in your own reasoning on these matters, much like those who are suddenly surprised when the world doesn't work the way they expect.

If you want to get into the difference between grammar and vocabulary, you have to remember that there is nothing really preventing us to define words as we choose, this is part of the evolution of linguistics, if you do not understand the definitions I have chosen to use, then rules of construction of statements do in fact appear different and the discussion does become one about grammar.

And another point, looking at accumulated population as a means for understanding probabilities shouldn't be foreign to anyone in physics. All probabilities in particle physics are essentially determined by looking at the occurrence of events with respect to accumulated luminosity. Counting the frequency of ideas within some set of some accumulated human population is no different in concept, if you add some sort of accumulated knowledge threshold, you find a perfectly naturally explanation for why groups of people studying similar problems start having similar ideas simultaneously. There are all sort of rabbit holes one can go down, but when similar people are looking at the same set of facts, it is relatively easy to understand that people will begin to make connections between those facts in way that can be only understood statistically. Again, I suspect that the truth of these observations and statements are getting caught up because people secretly want ET to exist and look a lot like themselves, much like the reason your having difficulty with basic concepts in this conversation.


reader Eugene S said...

you have to remember that there is nothing really preventing us to
define words as we choose, this is part of the evolution of linguistics,
if you do not understand the definitions I have chosen to use, then
rules of construction of statements do in fact appear different

I regret to inform you that a gentleman by the name of Humpty Dumpty preceded you to this point of view.

"I don't know what you mean by 'glory,' " Alice said.

Humpty Dumpty smiled contemptuously. "Of course you don't—till I
tell you. I meant 'there's a nice knock-down argument for you!' "

"But 'glory' doesn't mean 'a nice knock-down argument'," Alice objected.

"When I use a word," Humpty Dumpty said, in rather a scornful tone, "it means just what I choose it to mean—neither more nor less."

"The question is," said Alice, "whether you can make words mean so many different things."

"The question is," said Humpty Dumpty, "which is to be master—that's all."


reader anony said...

Well, if your associating me with one of the greatest popularizers of math in history then I can only understand this as meaning you agree wholly with what I am saying. Glad to see you join the party!


reader Eugene S said...

The trouble with millennials is that you've been coddled all your lives. No one bothered to rap your knuckles with a ruler to drive home the point that the possessive pronoun "your" is different from the contraction "you're". No one sent you to bed without supper because you insisted that "linguistics", "language", same difference who cares (they're two different words with distinct meanings).

Spare the rod, spoil the child. Your generation should be sent to North Korea to do hard, back-breaking labor on short rations for a year. That's what it will take to shake you out of your complacency. Alternatively, your family may hire me for an intervention, I do house calls but I must warn you that my services don't come cheap.


reader Shannon said...

When do civilizations succumb to religion? History shows a lot of ancient beliefs/religions that have completely disappeared. Religions might only slow down the pace of evolution depending on many different factors. Natural selection always has the last word ie the most adaptable to change will survive... and change is a natural process.


reader Shannon said...

I would bet Anony is a woman.


reader Gordon said...

Well, maybe the empty de Sitter space lasts indefinitely, maybe not. What about the cyclic models, like Penrose's conformal cyclic cosmology or others (Frampton, Steinhardt)?...I am not promoting any of them, just mentioning their existence.


reader Luboš Motl said...

Dear Gordon, by definition, the de Sitter space lasts indefinitely. If a space doesn't last indefinitely, it is not a de Sitter space.


The only similar subtlety in de Sitter space is the Poincare recurrence - after some super exponentially long time, events sort of start to repeat. But whether one should say that this is strict periodicity and the copies of the periodic evolution "lose their independence" is debatable.


Cyclic cosmologies can't ever allow the near-de-Sitter description to start to hold, otherwise the recollapse becomes impossible.


Given the fact that we know to be close to an empty de Sitter space from observations, it's really hard to see how the infinitely many recollapses in the future could be compatible with the empirical data.


reader Gordon said...

I am much less pessimistic about life elsewhere than you are. It just may not be "nearby". After all, the universe (not just the horizon one) is unfathomably large, maybe infinite (bounded or unbounded) and the number of stars and planets, myriad. There is robust research into the mechanisms of DNA/RNA life initiating on earth (metabolism first, RNA first models) as well as panspermia models...e.g. a bacterium, Dinococcus radiodurans can withstand intense radiation damage because it has super efficient and rapid DNA repair mechanisms and multiple copies of its genome.
Craig Venter is busy creating new artificial organisms, and then there is always silicon life in the form of self-replicating robots (Ray Kurzweil and his Singularity ((I think Von Neumann originated the term)--just injecting some speculation and Sci-Fi here :)


reader Luboš Motl said...

Dear Gordon, right, I sort of know you believe this and you're not the only one.


If you believe that RNA or DNA started it, what do you think is the shortest RNA/DNA (in number of bases) that produces organisms that are able to reproduce and "live" in some elementary way? Call this number N bases.


What's the percentage of the N-base codes that achieves the thing above? Isn't it tiny?


I think that if it were easy to create life "out of nothing", one could reproduce it in the lab - really from nothing while avoiding actions that are "extremely unlikely", like actions of an intelligent designer (Venter counts like an Intelligent Designer practician here!) - because some relevant steps in the lab could be sped up dramatically.


I think that if you lab-create any simple known terrestrial organism with a short DNA/RNA code, it will be possible to calculate that it needed quite some time to evolve.


reader anony said...

I think you're the one that has been spoiled rotten. I doubt you know what pain and suffering is. You grew up in a postwar generation that wouldn't know hardship from a can of spam. So before you think to add any more personal insults, I would offer you to go out and do something with your life before you start pushing daisies, because by then it will be too late :-)


reader anony said...

This is an interesting conjecture that I will leave unanswered since it will be fun to watch it play out.


reader Shannon said...

It wasn't a question ;-)


reader Gordon said...

Yup.


reader Gordon said...

Well, I do think panspermia is a viable alternative. We shall see, though, if self-reproducing organisms can evolve de novo in a lab. It may be a matter of time and ingenuity, maybe not.


reader Eugene S said...

I'll take that bet! ;)


Male college student, 22 years old, journalism major, habitual weed smoker, convinced you can bluff your way through every situation as if it were a bull session in the college dorm.


Career goal: a "job in the media".


Near-term goal: scraping enough money from his burger-flipping job to go to next year's Burning Man festival.


reader Shannon said...

Haha! I trust your judgement Eugene, but I keep my bet. Although the weed smoking must be what I could be mistaking for a female brain ;-D.


reader Shannon said...

Maybe they think it is junk mail ;-)


reader anony said...

I'm surprised though that you haven't been ostricated by the use of vocabulary, since conjecture and question would be viewed as different in Eugene's strict system


reader Peter Dunford said...

There is potential for thousands (maybe many times more) of civilisations to emerge across this galaxy. The probability that one of them exists at the right distance in the right timeframe to broadcast a signal we can hear is very low, possibly trending towards zero.


reader RAF III said...

Much of that sounds like Obama!


reader papertiger0 said...

Electro-magnetic railgun

http://www.youtube.com/watch?v=4OqlTXwLG40

Imagine it built on a space platform, scaled up to launch a pod with astronauts.

No need for propellant. If you miss your shot though, that could be a bummer.
One way trip.



It might be impossible. How do you mount a magnet powerful enough to sling a spacecraft to another star?


reader papertiger0 said...

Google ads. :P


reader Steve Reynolds said...

Most likely there are plenty of civilizations, but we are in a nature preserve with non-interference enforced by some of the most advanced civilizations.


reader Dan Park said...

It is ignorant of both history and evolution to claim that Christianity sole 1,000 years of progress, which is typical of those who argue on the basis of counterfactual claims.
To blame Christianity for the vicissitudes of the Middle Ages is to severely misapprehend the nature of cause and effect. The rise of Christianity in the Middle Ages came as a result of an existential threat to civilisation firstly from barbarians after the fall of the Roman Empire, and then in response to the Muslim conquests across Eurasian.
The Medieval period, characterised by Christian beliefs and customs, then laid the bedrock of many cherished modern institutions, including those for higher learning and for our legal system (inherited from Magna Carta).Moreover, this period laid the foundation for Western civilisation's current system of values and norms (predominantly Judaeo-Christian). It's no surprise then that the Renaissance and the subsequent Humanitarian Enlightenment arose uniquely out of the crucible of human civilisation. It didn't arise form the tribes and chiefdoms of African, nor from the teachings of Confucianism or Buddism of China, for from the mysticism of American Indians, nor from anywhere else.
To understand why this is the case we need to study the mathematical models for the evolution of cooperation. In a world everyone is out for himself, the winning strategy is always to be generous, hopeful and forgiving - all central tenants of Christianity.


reader Dan Park said...

Lumo's thoughts are always worth the time to hear.


reader Dan Park said...

o
It is ignorant of both
history and evolution to claim that Christianity stole 1,000 years of progress,
which is typical of those who would argue on the basis of counterfactual
claims.

To blame Christianity for the vicissitudes of the Middle Ages is to
severely misapprehend the nature of cause and effect. The rise of Christianity
in the Middle Ages came as a result of an existential threat to civilisation
firstly from barbarians after the fall of the Roman Empire, and then in
response to the Muslim conquests across Eurasia.

The Medieval period, characterised by Christian beliefs and customs, then
laid the bedrock of many cherished modern institutions, including those for
higher learning and for our legal system (inherited from Magna Carta).Moreover,
this period laid the foundation for Western civilisation's current system of
values and norms (predominantly Judaeo-Christian). It's no surprise then that
the Renaissance and the subsequent Humanitarian Enlightenment arose uniquely
out of this crucible of human civilisation. It didn't arise form the tribes and
chiefdoms of African, nor from the teachings of Confucianism or Buddhism of
China, nor from the mysticism of American Indians, nor from anywhere else.

To understand why this is the case we need to study the mathematical models
for the evolution of cooperation. In a world everyone is out for himself, the
winning strategy is always to be generous, hopeful and forgiving - all central
tenants of Christianity.


reader Dan Park said...

o
It is ignorant of both
history and evolution to claim that Christianity stole 1,000 years of progress,
which is typical of those who would argue on the basis of counterfactual
claims.

To blame Christianity for the vicissitudes of the Middle Ages is to
severely misapprehend the nature of cause and effect. The rise of Christianity
in the Middle Ages came as a result of an existential threat to civilisation
firstly from barbarians after the fall of the Roman Empire, and then in
response to the Muslim conquests across Eurasia.

The Medieval period, characterised by Christian beliefs and customs, then
laid the bedrock of many cherished modern institutions, including those for
higher learning and for our legal system (inherited from Magna Carta).Moreover,
this period laid the foundation for Western civilisation's current system of
values and norms (predominantly Judaeo-Christian). It's no surprise then that
the Renaissance and the subsequent Humanitarian Enlightenment arose uniquely
out of this crucible of human civilisation. It didn't arise form the tribes and
chiefdoms of African, nor from the teachings of Confucianism or Buddism of
China, nor from the mysticism of American Indians, nor from anywhere else.

To understand why this is the case we need to study the mathematical models
for the evolution of cooperation. In a world everyone is out for himself, the
winning strategy is always to be generous, hopeful and forgiving - all central
tenants of Christianity.


reader Gordon said...

Frigidaire---Don't worry--Lubos thinks that everything is left-wing propaganda :)
But I do agree with his answer below this. And despite the fact that E.O. is an elegant writer, I agree with Pinker that group selection has been hyped and is not an evolutionary driving force except marginally.


reader anna v said...

If the organized church had adopted Demokritos and Aristarchos etc as the basis of "allowed" physics by its dogma, scientific history would be different. It was the dogmatism of creation that chose the physics and imposed it on the few literate people of those times. The humanitarian tenents of christianity during the middle ages were buried in dogmatism and inquisition practices.


reader anna v said...

you should delete the duplicate posts


reader Dan Park said...

I apologise for the duplicate posts. I deleted them, but now they appear as Guest posts.
You haven't addressed any of my points. You're merely indulging in more counterfactual thinking, which is contrary to the principle in scientific enquiry of learning by empirical observation. It is not for you to say what could or would have happened had the Church adopted this or that philosophical framework.
Historical forces towards human progress can be modelled within the framework of the Pacifist's dilemma, which is a renaming of the Prisoner's Dilemma. the incentive structure is set up so that it's always rational to be the aggressor. What the dogmatism of creationism did was jigger the payoffs in the afterlife which thereby changed the perceived incentive structure in this life towards pacifism. It's pure conjecture to posit that, in that historical context and at that stage of human intellectual development, similarly effective outcomes could have been achieved by adopting the philosophies of Democritus or Aristarchus.


reader anna v said...

But it is a fact that the church chased anybody who would support the heliocentric system, and that was based on aristotelian physics. When the church's and the inquisitions grip lessened rational thought could be applied to the scientific problems. And were the crusades an expression of your "pacifism" ?


reader Shannon said...

"Ostricated", wow.


reader Dan Park said...

I don't deny that the Church was decidedly anti-science for an extended period during the Middle Ages. But it's a fallacy to think that the pursuit of scientific knowledge is a causal factor in human flourishing in an age when sovereignty is conferred by right of conquest. Examples about. Democritus's wisdom was availed to the Ancient Greeks, and yet its civilisation fell under the weight of infighting.
In an evolutionary sense the civilisation that prospers will be those that adopt the optimal strategies for cooperation, be them what they may. The more egregious Christian practices such as the inquisition were miscalibrations of a strategy that ultimately enables and bequeathed to modernity the Renaissance and then the human Enlightenment.
You can't simply co-opt the Crusades as a wholly negative event in the history of Christianity when there exists a body of historians who view the Crusades as a part of a purely defensive war against the expansion of Islam in the east. Consider that Christianity would have fallen under the sword of Muslim conquest in the eighth century if not for the Battle of Tours. The ancient religion of Zoroastrianism was completely wiped out by Muslim conquests, and perhaps the one thing that saved Christianity was its willingness to defect when its opponent does.
Thus the aggression of the Crusades can be explained within the framework of an iterated Prisoner's Dilemma whereby the optimal pacifist strategy is to first cooperation and then only defect when the opponent defects.


reader imho said...

A Billion is a pretty small number in the grand scheme of things. Rare earth hypothesis says that we are likely alone in this galaxy... which unfortunately is consistent with the data. How boring! I guess we are God and it's up to us to send our robot offspring to colonize the galaxy.


reader cynholt said...

I love your stargazing, Lubos, especially if you're gazing at the stars
of de Sitter space. It's good as well as essential to keep hope alive,
and you always manage to see hopeful patterns among the stars, even if
these patterns lie within the infinite obscurity of de Sitter space.
This allows me to have hope that another world is possible under this
sun, or some other sun.



http://www.youtube.com/watch?v=fz4F-kOnisc


reader gary said...

Why couldn't they calculate pi to 100 decimal places? Well, for one thing, maybe
they wouldn't be working in Base 10, since most of them didn't have 10 digits/fingers.
See: "The Dragons of Eden: Speculations on the Evolution of Human Intelligence" by Carl Sagan.


reader Smoking Frog said...

What is the evidence that dinosaurs couldn't have calculated pi to 100
decimal places? It seems that they didn't use too many modern-like
machines (no traces of them) but they could still be vastly smarter than
we think.



More modestly, maybe some of them were as intelligent as the African grey parrot, which can handle three concepts at the same time, e.g., "Give me a blue plastic triangle."



If some dinosaur species had made machines, would we find traces? Wouldn't they be totally oxidized, etc.?


I've wondered if there was a human civilization much earlier than our own, e.g., during the last interglacial. We have failed to find, and then found, far more recent things.


Bill


reader Eugene S said...

I do not have a reference for this sorry, but apparently our decades of burning coal have laid down a sufficiently thick deposit that sediments 100 million years from now would show a trace of it. Not a big trace, but perhaps no thinner than the iridium anomaly at the KT boundary. As no such 100 million year old sooty layer has been found, no one before us had a technological civilization.


reader Rehbock said...

He is missing two fingers. Like children everywhere educated with Sprout and Sesame Street he always used base ten.
He lacks vocal cords and mostly points out the letters and numbers to - like Steven Hawking - communicate.
He knows that pi is a bit bigger than 3 and its relation to circumference- my teaching not the TV's.
He learns visually, is good with shapes and undweardimensions.
He can do the four arithmetic operations with integers. He understands some geometric concepts and simple operations like square or root for same. His favorite number is 8. From what he has told me he likes it's symmetry and that it also means infinity - too big to think. He says all numbers are imaginary and that heis better with words, anyway. Probably so.
He knows he can think and that makes him a genius.
He is not sure about some people - but he knows our host by image and that he is a genius, too.
He also knows he is a bird and has 8 talons and that humans have ten fingers. Also he explains that he has three wings - the two wings that humans call wings and his tail.
Really not joking and he is not trained to do tricks. He is Boo, my avatar. He has obliged to provide the pi symbol in his favorite yogurt.
So why would the gray bird want the blue triangle?


reader Smoking Frog said...

That does work for "modern-type machines," but human civilization began thousands of years before the recent century+ of burning a lot of coal.


reader Chuck Bradley said...

I once used a computer with an unusual instruction format. The opcode was spread across four bytes of the instruction. The designer of the hardware said this was a feature to prevent patching object programs. We patched anyway and wrote tiny programs in machine code. I fully agree, complexity might slow down understanding, but it does not prevent it.


reader Eelco Hoogendoorn said...

My take on this is that interstellar travel is just much harder than the average scifi nerd would like to believe; if not impossible.

GR may not say that wormholes are impossible; nor does the theory of evolution say unicorns are impossible. But im willing to take a bet that neither actually exist. Well be genetically engineering unicorns long before we ever engineer a wormhole, to be sure.

Flying anywhere interesting at subliminal velocities is a somewhat retarded undertaking; a lot of time will pass on your ship before you get anywhere. A small closed system like that will have big trouble with entropy. Not only theoretically, but also just the whole thing falling apart due to infighting over many generations. And you arnt really getting to any other galaxies this way; the universe is already too old for that.

Traveling fast enough so that the local passage of time is a nonissue is an interesting idea; but whatever your hull is going to be made out of, it had better not be any of the known particles, if it is to survive interstellar gas. Even a few particles per cubic meter add up, given enough meters. And they hit your hull hard enough to transmute the fuck out of it. Oops. Maybe you have some clever idea of deflecting all that; but then there is the more than balmy temperature of the background radiation to worry about as well. Hint: titanium isn't going to cut it.

As a fundamental point; Just because bosons are known to travel between galaxies, does not mean it is at all possible for fermions to do the same, and arrive at their destination in anything resembling their original configuration. There certainly isn't anything resembling an established precedent for this. Even in its most abstract form, its pure scifi.

There are probably many civilizations out there, but unless they happen to be within a handful of lightyears, I doubt well ever shake hands. And the number within such a short radius may very well be zero.


reader Casper said...

Its a relief to know that our physicists are still rating themselves as the top brains of all time and space. What would we do without them?


reader cameron said...

Perhaps (however unlikely it is) we are the most inteligent race in this portion of the galaxy (i hope not though, because we are REALLY stupid). Or maybe there are races that have in fact conquered vast swaths of the galaxy, but have left us alone and in the dark for some reason( feel free to speculate on that reason or not, as you will)


reader cameron said...

I dont think thats the most likely, but its certainly the one i want to believe :)