49 thoughts on “If Aliens Exist”

  1. Reading through the comments on that old thread, a lot of folks suggested that aliens wouldn’t detect digital transmissions where they would zero in on analog signals. I think that’s a crock – it just takes computing power to decode signals from the noise, look at what we’re doing with the SETI research. It would be wise to assume a higher tech civilization would have the ability to pick out our digital signals as well.

  2. “if aliens just don’t like us, there’s no need to invade. They could send a half-pound of deadly nanodevices on a stealthed probe. We probably wouldn’t even recognize what was happening as an alien attack.”

    I know. They would act like Progressives.

  3. Easterbrook’s argument doesn’t pass Biology 101. “Survival of the fittest,” as used by biologists, simply does not mean what he (and many other journalists) think it means. It means survival of the organism that is *best fit for its ecological niche* — nothing more and nothing less.

  4. I’ll bite, Edward — what would the “best fit for its ecological niche” look like for a Type III civilization?

  5. Titus, welcome to tautology club. What would “best fit for its ecological niche” be for an organism that used all of the natural resources and energy of planet Earth? Why aren’t we afraid of such organisms?

  6. Why aren’t we afraid of such organisms?

    Because we are they. The chances of ET living on a planet exactly like Earth are zip, and that means he’s more suited for his planet and we for ours.

    Anyway, I think the argument is silly. There are only two possibilities:

    (1) Intersteller travel is, or can be made to be, cheap, relative to (say) terraforming planets within your own stellar system, figuring out how to do large-scale transmutation, constructing orbital habs, building a Dyson shell or Ringworld, et cetera and so forth — all the other means of acquiring new resources.

    (2) Intersteller travel is by nature much more expensive than any of those things, although intersteller communication is not.

    It’s only in case (1) that it would be economical (= practical) for ET to invade and conquer. But in that case, cheap interstellar travel means he can just go off and invade and “conquer” an Earth-like world that doesn’t have an annoying semi-intelligent species of potential guerilla and saboteur, or at the least he can relocate us via some interstellar “Trail of Tears” instead of exterminating us (which we’re bound to resist vigorously).

    I’m not counting on ET’s enlightenment and good morals — since I agree evolution has an iffy relationship to either — I’m counting on his self-interest and good grasp of economics, and I do think natural selection brutally enforces such expertise among successful technological social species.

  7. Titus, welcome to tautology club.

    “The first rule of tautology club is the first rule of tautology club!”

  8. Well assuming speed of light limitations on expansion intelligent life will likely quickly evolve to use all available local energy and resources – solar systems will go dark, so to speak as that life expands out from its original home solar system. Solar systems will perhaps evolve a thin membrane of life that completely surrounds the sun not allowing any high energy photons to escape. (Something we should probably be looking out for in the night sky.)

    If we assume that life will eventually evolve to the limits of available solar systems – until it takes over most every solar system in the universe, and that there will be multiple life seed points to begin with, then, at the end, the species with the most suns wins. While there would be various alliances a sensible strategy would be to detect any new life sources at the earliest possible time and send out near light speed “bombs” to destroy them at the first available opportunity, thus preventing them from becoming future competition.

    Personally I am hoping that unending expansion and growth will be the order of the universe, then everyone gets to be mostly nice to one another.

    I would also note that even if life only starts in one place, it will soon speciate resulting in competition between species. Not that there would be any less internal competition within just one species…

  9. Our local cluster has an abnormally high Fe/H ratio. Earth itself has an unusually high Fe/H ratio relative to our solar system. The crust is thought to possibly have an unusually high proportion of metals due to the possibility of an Earth-Moon collision. The rate-limiting pieces in chemical reactions are typically the rarest participants, not the most common participants. The facts that we’re ‘bags of water (H2O)’ and ‘carbon-based life’ are completely true looking at percentages and internal coding mechanism. But crucial activities rely upon elements much farther down the periodic table. Hemoglobin – iron. (Some critters use hemocyanin instead – copper.) Calcium for bones. Potassium….

    When you sit down and start adding up “Ok, by how many -generations- of supernovas generating useful bits are we actually ahead of the game?” I get to the anti-Galileo position. That is, we might well be exceedingly unusual for this date. “Life” in general across the universe is generally billions(!) of years behind.

  10. Something we should probably be looking out for in the night sky.

    Even if Dyson spheres are not something we’ve been looking out for, they’re something we’d have noticed anyway, right? Even if we didn’t notice that a “red dwarf” had a ludicrously large radius, surely we’d notice that it had the smooth spectrum of radiative cooling fins rather than the sharp lines of stellar plasma.

    The fact that we haven’t been noticing any such technology is a little worrying. Let’s hope that someone like Al is correct about the reason why, and that the Great Filter is behind us rather than ahead.

  11. I don’t think it’s possible to independently measure the radius of stars unless they are very close or perhaps unusually active, roy. But I think you’re right about what would be noticeable lack of absorption lines in the spectra of Dyson spheres.

    And don’t forget about the background 3K radiation. Maybe the First Species has already enclosed the entire observable universe in a Dyson sphere, the selfish buggers.

  12. I have no idea what dark mass or dark energy are, but part of me is suspicious of a very large quantity of mass and energy that seems to waste little energy on the rest of the universe. Has the proportion of dark mass changed significantly over time?

  13. I don’t think there’s any way to know, Pete, as the only “evidence” for dark matter is the peculiarly fast and tight orbits of outer stars in galaxies. It’s dark energy that has cosmological significance, I believe.

  14. When you sit down and start adding up “Ok, by how many -generations- of supernovas generating useful bits are we actually ahead of the game?”

    If I read Al correctly, he’s giving evidence for my thoughts — that we are very likely the first living planet in the universe. I’ve read that our sun is a third generation star, and in the set of integers from 1 to infinity, 3 is a very small number by any reasonable standard.

    Has the proportion of dark mass changed significantly over time?

    When the universe was ~400,000 years old, dark matter was >60% of the universe, and the rest of it was evenly distributed among photons, neutrinos and “ordinary” matter. Now the universe is about <5% "ordinary" matter and the rest is 3/4 dark energy and 1/4 dark matter.

  15. We could always create a War of the Worlds scenario and fake the destruction of Earth in a massive nuclear holocaust and beam it out then shut down all other transmissions.

    Of course there might be some alien civilization out there who feed off radio active waste or otherwise find it as hospitable and how convenient that this newly discovered planet is also free of any inhabitants.

    (Don’t try and ruin a poor joke with science)

  16. Reading through the comments on that old thread, a lot of folks suggested that aliens wouldn’t detect digital transmissions where they would zero in on analog signals. I think that’s a crock – it just takes computing power to decode signals from the noise, look at what we’re doing with the SETI research. It would be wise to assume a higher tech civilization would have the ability to pick out our digital signals as well.

    The thing I’ve often speculated about on SETI is that we’re using our technology and assuming others out there would be as well. Given as we only have a dataset of one when it comes to known planets with intelligent life, it’s hard to make any firm conclusions about patterns of technological development on other worlds. However, it’s possible there may be a rather narrow timeframe when detection of radio signals is possible.

    Consider this: if an alien civilization had trained it’s SETI antennas on Earth 150 years ago, what would it have heard? Nothing because no one was transmitting yet. Given that low power and low frequency signals are unlikely to be distinguishable from background noise very far from the Earth, you might have to go back as recently as 70 years or so ago before you’d find detectable signals from the Earth.

    Now, consider this: If an alien civilization develops SETI technology 100 years from now and trains their antennas on the Earth, what are they likely to hear? Quite likely, nothing because we will likely be using other means to communicate in the place of high powered RF transmissions and may not even be using radar any more.

    If my hypothesis is correct, an alien civilization would have a window of less than 200 years to be able to detect a signal from us. Hypothetically, the same limitation would apply to us trying to detect them. Even though there could be millions of planets with intelligent civilizations in the universe, it’s possible the window of opportunity for detecting those civilizations makes it very unlikely we’d ever do so.

  17. an alien civilization would have a window of less than 200 years to be able to detect a signal from us.

    Agree. The way I think about it, every bit of radio energy that spins off into space is a measurement of inefficiency. As we mature, our efficiency will increase until there just isn’t that much left for outsiders to detect.

  18. The way I think about it, every bit of radio energy that spins off into space is a measurement of inefficiency.

    There is an exception in the case of high powerd radars like BMEWS and PAVE PAWS. By design, these radars emit powerful signals into space to detect and track missiles and satellites. It’s possible that given the characteristics of these radar emissions, they might be the most detectable RF signals radiating from the Earth.

  19. Titus, “First in the Universe” isn’t necessary. Just enough to make it much more sparse than expected. The discussions of the Drake Equation keep coming up with a density for life that would mean there really should be some inside “our detection envelope”. I happen to think we’re particularly lucky with regards to the elements-past-iron, and this isn’t adequately factored in.

    There have been a couple of peer-reviewed published papers that state pieces of my view here over the years, but I haven’t kept track of the citations well enough to point. I haven’t seen anything putting all three of the pieces together, but it isn’t my field either.

    This is from notes in 1993, but the plot at the time was log ([Fe]/[H]) vs Age(10^9 years). This leads to a decent linear fit. Sol was roughly two standard deviations ‘high’, and shifting Sol to the fitted line was ~10^9 years.

  20. Rand I am amazed at the quality and quantity of posts you’ve made on the Tucson shooting. We don’t have to speculate about aliens. That gunman was a fine example. This post is such a huge topic but I do want to address one point…

    Intersteller travel (1) can be made cheap (2) is by nature expensive.

    Misses the point. We already can envision ways to send life to the stars with existing technology. The cost of doing it, whatever it is, is trivial compared to what life does once set in motion in a new environment. It is the time delay of communications that is relevant.

    The new batch of aliens may not relate to the old batch so it’s a new ball game. The old batch will have continued development (especially considering relativistic differences.) The new batch will start at whatever technology level they can take with them which likely may be far superior to our own.

    Likely they will serve men… for dinner.

  21. But ken, I was specifically addressing the question of conquest or exploitation. Sure, the aliens can kill us long distance…er, assuming they can deduce our DNA spectroscopically and build deadly viruses…but they can’t harvest our brains and take them back to the home planet for consumption, even at gourmet prices, unless interstellar travel is cheap and easy.

    If what you are suggesting is that they can colonize us long distance by sending the killer viruses and a package of their own germ cells plus artificial womb, whatever, then…er…I guess so. Sounds more or less like updated panspermia, however. For all we know we are the descendants of interstellar invaders of Earth, or at least the latest wave of such.

    But it’s not still not clear to me it’s economical as a general policy, i.e. excluding the occasional Hitler from Epsilon Eridani. An invincible invader, one not subject to defenses from the home world — let us recall our own bacteria would love to feast on complex alien compounds, not to mention that the newborn aliens will need schooling and time to learn to speak, walk, and build super death-ray blasters according to the microfilmed blueprints from HQ, during which they would seem to be vulnerable to, say, atom bombs — would be a pretty heavy object, by definition. Back to the necessity for cheap interstellar travel.

  22. Pete,

    Robert A. Heinlein and Spider Robinson’s book, Variable Star, is just about this theme of aliens doing their best to take out future competition. I would make it mandatory reading for any astronomer who wants to send a SETI signal out to ET…. Its kinda like a sunbathing Gopher waving a friendly hello to get the Hawk’s attention as he flies over 🙂

  23. If we want to talk disturbing literature about aliens discovering us first, take Larry Niven’s Known Space. None of the books really lay the entire story out for perusal, but the Puppeteers think we’re cockroaches that can be repeatedly culled and then bred for explosive ordinance removal.

    Then there’s John Ringo’s Posleen series, where we’re a handy food source. And they aren’t the most irritating alien species in the books.

  24. I probably made one of the prior comments about incompatibilities between radio in 1901 (Marconi’s first trans-Atlantic transmission) and today. In 1901, no one could have understood a digital signal — or recognized it as a communication protocol. The point is that in 100 years, we have evolved radio communication to the extent that it would be unrecognizable to its pioneers. There is no reason to suppose that we have reached the end of that evolution. So the odds of there being a civilization near enough for us to detect (100 light years is a stretch, and there are only about 550 G class stars in that radius), and synched in evolutionary time to the point where we’d be able to detect whatever signals they use (and vice versa) is exceedingly small.

    Beyond that, I would say that if evolution plays a similar role in ET cultures as it does in ours, then the appearance of NASA would signal both the beginning and end of that cultures expansion into the universe.

  25. but they can’t harvest our brains and take them back to the home planet for consumption

    That’s adding complexity not required to a successful invasion. It’s not so much strategy or tactics that win wars, it’s logistics. There’s no need to bring back brains beyond a sample to show the home crowd. Here’s the scenario…

    Earth can’t get a colony on its own moon, but the Glebtarfaarbs have been sending automated ships (w/ Education and frozen biologicals) to within the oort cloud of every star within 100 lightyears of their home which happens to include the SOL system.

    Today their are about a trillion of them living in the Keiper belt and they’ve received a signal from the home world via instantaneous EPR radio that now is the time for all good Faarbs to make their Glebtarian ancestors proud and eat some human brains. Plus their really pissed that the music on that one golden record we sent them really sucked and their hasn’t been another in the last forty years.

    The homeworld doesn’t have to conquer us or even reap the benefits other than knowing another potential adversary has been taken care of by their spawn.

  26. But ken, why are the Sol-born Glebbies taking orders from the home planet? Clearly none can have any personal loyalty to a world they’ve never seen, for generations. (Indeed, given the cosmic ray flux out there where Sol’s magnetic field is weak, it’s likely the two branches of Glebdom don’t even look the same any more.) It’s not like such orders can be enforced. Indeed, the home Glebbies can’t even monitor whether their orders have been actually carried out.

    Why wouldn’t the Oort Glebbies just signal home Mission Accomplished! and go back to sharing illegal MPEGs of heterotic strings pleasuring themselves with Dirac spinors from the Interoortnet — or whatever warms their triple-chambered reptilian hearts out there? Why bother announcing themselves and running even the slight risk of harm pitiful humans present? I don’t bother wasps if I don’t need to. (And if they’ve been thriving in the Oort Cloud they’ve little need of the Earth’s by contrast meager resources.)

  27. Post-script: I should add, ken, that I don’t bother wasps even knowing that if not exterminated then in 50 million years they could evolve into nearly invulnerable 7-foot armored hyperintelligent waspoids that would threaten the very existence of my great-great-great-…-great-grandchildren. Short-sighted, I know — but why would we think the individuals of an alien species would be any less selfishly inclined to prioritize what happens in their own lifetimes?

  28. Even if Dyson spheres are not something we’ve been looking out for, they’re something we’d have noticed anyway, right?

    Depends on when they were built. The night sky is a radiant time capsule. If some folks, friendly or not, built a Dyson sphere on the other side of our own galaxy as little as 50,000 years ago, we wouldn’t know about it yet as its odd spectrum would not yet have arrived in our sky. Likewise, the Andromeda galaxy could be full of Dyson spheres over 2 million years old, but we can’t see them because were still seeing how things were over there 2.5 million years ago, not how things are now.

    One can even assume it to be increasingly likely that Dyson sphere builders have been at work the older the target stars are, but those stars are also further and further away and, thus, we’re still awaiting the arrival of the requisite spectral evidence. It’s entirely possible that the universe is simply lousy with Dyson spheres at this precise instant and yet, for reasons of time and distance, that we cannot yet see a single damned one of them. Zephram Cochrane (or Nels Bergenholm), where are you when we need you?

  29. why are the Sol-born Glebbies taking orders from the home planet?

    Because that’s the way they’ve been genetically programmed. That question absolutely had to have been addressed before the process was initiated. They have no more choice in the matter than they have in not pleasuring themselves with Dirac spinors, which also was programmed ahead of time.

  30. Some of the aliens might want us as pets.

    We can only hope that the spore of artificial space mold, which expands across the galaxy building Dyson spheres, finds us interesting.

  31. I saw some interesting comments in the earlier “don’t shout” post linked to from here. (I’m responding to them here since the older post is from 2008 and the discussion on that post is done.) Comments such as:

    “I think that this is a similar case where people should be enjoined, by force if necessary, because we cannot know the consequences.”

    “I believe the main point of his article was not necessarily that we should not consider ‘shouting’ to the stars, but that the idea may affect so many and is being discussed by the relatively few. … I do not have the moral authority to put the rest of the planet at risk, especially without at least some discussions at a higher level than just a few of my friends.”

    “Does anybody here think that a few people should be allowed decide, on their own and without debate or permission, to do something that has an expected casualty impact of 600,000 human deaths?”

    Now think of those comments in the context of global warming. I don’t want to get in to a discussion of whether global warming is actually happening or not, but does an individual have the right to unilaterally decide that global warming is not a risk and unilaterally decide to emit carbon dioxide, or should they be required to abide by “higher level discussions” where everyone that could be affected gets input into what “we” think the risks are and the limits on behavior should be?

    Mostly I’m just suprised to see those comments made in this forum.

  32. Or, we could have a situation similar to the Futurama episode When Aliens Attack where Fry disrupts the transmission of an episode of ‘Single Female Lawyer’. The aliens of Omicron Persei 8 grow angry that they now do not know how the episode ends and invade the Earth to demand that we resume broadcast of their favorite sitcom. Of course, the Neilson ratings never bother to poll the viewing habits of the Omicronians so we’ve no idea the true level of interest in our sitcom culture.

  33. Because that’s the way they’ve been genetically programmed.

    I thought someone might say that. My trap has sprung! Two points, Curt: first, we all here agree, I think, that man is a better explorer of the cosmos than robots; men are more flexible, innovative, adaptive, intelligent, et cetera. Far more likely to survive the challenges.

    Indeed, it would seem unlikely you could program robots to conquer an alien intelligence — because, among other things, any device or mechanism that is slavishly devoted to duty is ipso facto a double-edged sword. That is, robots that always follow orders are dangerous because they can be reprogrammed, and will follow the new orders just as slavishly as the old ones. They have, after all, no independent judgment that allows them to question orders.

    What’s to stop us from reprogramming the bot-like Oort Glebs so they slavishly obey our orders instead of the home Glebs? Or, if that seems far-fetched — e.g. we’re not smart enough — what’s to stop one mutant Gleb in which the obedience chip has shorted out from reprogramming his normal pals so that they all follow his orders instead of Gleb HQ’s? It would happen, absolutely. Any programmable and powerful system attracts viruses, as we sadly know. Indeed, it’s often thought that one of the main purposes of intelligence and self-awareness is to immunize individuals against memetic (as opposed to genetic) viruses — we are self-aware so that we know when someone is trying to “reprogram” us with different values, different goals, et cetera.

    Those smart interstellar-faring Glebs will know both these points. They will want their distant cousins to succeed, first, and they will definitely not want them to be turned into race traitors by Earthly reprogramming guerillas. So they will not program their descendants for slavish obedience to orders.

    Second, the assumption here is that the Glebbies care about populating Earth with Glebbies, Mark I. If they just cared about populating Earth with some intelligent, self-propagating species to whom they could talk — why bother invading? They could just talk to us! We assume they treasure their particular genome, cultural values, popular TV shows.

    But if that’s the case, they can’t very well change their descendants so profoundly — by installing slavish obedience DNA — that they (the descendants) no longer remotely resemble the stay at home Glebs. That defeats the entire purpose! Might as well send shiny metal robots, and we all know that having a robot wave to you from another planet is just not the same rush as having a fellow human being do so. Would the Glebbies think differently? Surely not! Racial pride is racial pride everywhere, as several episodes of Star Trek averred.

  34. Question, why do folk expect life elsewhere to be chemically and combinatorially similar to that on Earth?

    Because the only way you can build a mechanism that is (1) stable but (2) can change portions of its internal structure as needed, in a very controlled way, appears to be to take advantage of two sets of interactions between molecules that are widely separated in energy scales. That way, you can build your “permanent” stuff out of interactions at the high energy scale, and build your “moving parts” out of interactions at the lower energy scale. At operating temperatures, well below the upper scale but close to or a bit above the lower, your permanent cylinders and pistons and crankshafts and transmission gears are all stable but your “fuel” readily combusts, and your “oil” flows, and various other useful chemical transformations necessary for your mechanism to work proceed.

    Remarkably, we know of only one such distinction between chemical interactions: the scale between covalent chemical bonds (10² kJ/mol), which become labile at a few thousand degrees (flame temperatures), and hydrogen bonds (10 kJ/mol), which become labile in the temperature range (aha!) where water, the most common hydrogen-bonding substance, is a liquid.

    Since no one an think of how to build a molecular machine that doesn’t exploit the distinction between covalent and hydrogen-bonding energy scales, the assumption is that any form of life will have to do so, and therefore the sine qua non of life is hydrogen-bonding substances, i.e. water, and temperatures right around the place where hydrogen bonds can be made and broken with ease using energy from the environment, i.e. in the liquid range of water.

    The most plausible alternative of which I’ve ever heard is Robert Forward’s set of novels beginning with Dragon’s Egg, in which he imagines a species that exploits some (unknown) equivalent distinction in nuclear interaction energies. They live on the surface of a neutron star, presumably where the temperature is above the lower energy scale. Interestingly, since the distances and speed of nuclear reactions is fantastically smaller and faster, respectively, than for chemical reactions, the cheela are tiny and their perceptions and history fantastically faster than ours.

  35. My trap has sprung!

    Uh-oh.

    we are self-aware so that we know when someone is trying to “reprogram” us with different values, different goals, et cetera.

    As an aside, I don’t think I’d extend that “we” to a percentage of the h sap population in excess of 50.

    So they will not program their descendants for slavish obedience to orders.

    Not in a way they’d notice. Ken’s starting point was:

    The homeworld doesn’t have to conquer us or even reap the benefits other than knowing another potential adversary has been taken care of by their spawn.

    “Adversary” doesn’t seem to be tied down in this thread, though there was the mention of human brains for food. But “spawn” doesn’t definitively imply Glebbies, Mark I.

    If they just cared about populating Earth with some intelligent, self-propagating species to whom they could talk — why bother invading? They could just talk to us!

    They don’t want to, remember they’re pissed about the music on that golden record. We don’t know why they’re pissed (I’m not aware if we put a rap sample on it or not), but we can assume it’s related to our lack of diversity. In our defense there’s only so much you can fit on a single record, but that isn’t going to assuage them.

    No, I think they’d use a carefully designed genetic code, and take the risk of our reprogramming them. They’d probably add a few sequences that would cause brain explosions if it was meddled with inexpertly. Maybe a specific type of music would trigger it and we wouldn’t need to reprogram them after all. Did we keep copy of that damn golden disk?

  36. Regardless of the content of the transmission a Type III civilization would interpret it as “moo”, then respond. Frankly I don’t like the odds. Leave me in my anonymity, in my far flung field.

  37. They don’t want to, remember they’re pissed about the music on that golden record. We don’t know why they’re pissed (I’m not aware if we put a rap sample on it or not), but we can assume it’s related to our lack of diversity. In our defense there’s only so much you can fit on a single record, but that isn’t going to assuage them.

    Thankfully, the Voyager record predated rap “music”, otherwise they’d have good reason for wanting to destroy us all. I could hardly blame them.

    No, they’re actually pissed about the plaque. You see, they’re prudes who’re offended by the nude human images. That, and their feminists are mad that the female is shown slightly smaller than the male on that plaque.*

    *Believe it or not, some Earth feminists raised a stink about that very issue, that and the stink raised by their unshaved armpits.

  38. Well, Curt…let me put it this way. What is the one aspect of being human beings, instead of, say, draft horses or Galapagos tortoises (which live much longer) that we all prize above everything else? What beats butter pecan ice cream, a good-fitting pair of comfortable old jeans, a new Tesla — even tickets to orbit on Dragon for you and the member of the appropriately opposite sex, all expenses paid?

    Is it not liberty, particularly our liberty to think and act as we please? Isn’t that what would make us — has made us — fight to the death rather than accept the yoke, the collar, the leash? Would we consider it of any interest whatsoever to be given passage on an interstellar liner to a new planet — if we were simultaneously utterly deprived of our freedom of action, even our freedom to think? I say no! (To accompaniment of loud cheers from the audience, waving hands, tentacles, manipulators, holding assorted weapons and totems of potent battle gods.)

    I think the Glebs are on my side, metaphorically speaking. I just can’t see a species having tasted the glories of intelligent, aware, free thought willing to give that up in all eternity for the dubious and temporary honor of conquering the slime beings of planet Earth.

    And if they’re not intelligent, or they are willing to turn themselves into robot zombies — why, I bet we can take ’em. History suggests numbers (or even, in the case of the big lizards, weight of armor) are no match for self-aware free-thinking intelligence.

  39. There is another argument that evolution will eventually converge on a standard form through out the universe and so to some extent it does not matter now who lives and dies, just so long as something lives. Indeed I would see this as the first priority of life on this planet (that it ensure that something lives).

  40. Carl Pham – interesting, but I can think of at least one other pair of interaction types to fit that bill – hydrogen bonds and van der Waals forces. This would probably come into play at Titanian temperatures, or thereabouts. In addition, there is at least one other hydrogen-bond dominant system with a slightly lower temperature range; liquid ammonia. Especially at slightly higher than Earth pressures, this might serve. Liquid HF might also work – but flourine is too rare for this to be likely.

  41. I think you’re mistaken, Fletch. Hydrogen bonds are actually generally classified with the other van der Waals interactions (London forces, et cetera) although that’s a bit misleading, I think, since van der Waals interactions are strictly classical and hydrogen bonds, like chemical bonds, partake of nontrivial quantum character.

    In any event, the energy scales are very similar. You need energy scales that are widely separated, e.g. by 2 orders of magnitude, as are H-bonds and chemical bonds, so that you have plenty of room to play.

    Er…unless I’ve entirely mistaken you, and you were saying some other van der Waals interaction could take the place of H-bonding, and we keep chemical bonding for structure. Yes and no; I mean, we already make great use of other van der Waals interactions besides H-bonding. (I’ve seen fascinating proof that E. coli make use of the nonideality of their protoplasm to help them cope with unusually salty media.)

    But the beauty of H-bonding is that it is directional and saturable, like real chemical bonds, so we can, for example, rely on it to keep the two strands of our DNA matched up perfectly, match transfer DNA to the appropriate amino acid, and so on.

  42. It’s not that the spawn are robotically programmed. The control from the old system is propaganda and not every triple-chambered reptilian heart beats to the same rhythm.

    During the British invasion there was quite a debate at the Pluto monitoring station if the invasion was coming after them?

    But it’s brains that yer forgetting. Night of the living dead convinced them it’s the ultimate food source and the home system has been reinforcing that meme for about a thousand years.

    Even with internal disagreement (the hearts and livers crowd) they all agree that they need to serve man (on a ceremonial Krods shell platter of course.)

Comments are closed.