Except for rare occasions, I don’t play the lottery. Like many of you, I consider state-run lotteries to be a tax paid only by people who can’t do math. That’s kind of arrogant coming from a guy who chose to go into biology rather than engineering specifically because he’s bad at math, but I know enough to know that the odds are never in your favor, and that I’d rather spend my money on just about anything else.
But I’m beginning to get the feeling that, unlike myself and many others, Harvard professor Avi Loeb just might be a fan of playing the lottery. That’s not meant as a dig. Far from it. In fact, I readily concede that a physicist with an endowed chair at Harvard working in astrophysics knows a lot more about math than I do. But given his recent news splashes where he waxes on about the possibility that Earth has been treated to both near misses and direct hits from interstellar visitors, I’m beginning to think that maybe I’m looking at the lottery backward.
Odd Odds
Whenever someone challenges me on my “tax on the innumerate” position — and here I risk exposing my poor math skills — I explain my position thus: to express the 1 in 300 million odds of winning Powerball as a decimal you have to write down an awful lot of zeroes before you start writing any other numbers. To my mind, a number with eight zeroes after the decimal point is indistinguishable from zero, which makes me confident that it’s essentially impossible to win the lottery. QED.
“But,” the lottery lover inevitably cries. “That number may be small, but it is definitely NOT zero! Somebody has to win, and it might as well be me.” While it’s demonstrably false that “someone has to win” — plenty of lottery drawings result in no winners — the photos of people posing with oversized checks prove that people do win. That’s sort of confounding to me, because if my position that 0.0000000033 is the same as zero were correct, nobody would ever win. Checkmate, disbeliever.
But what does the lottery have to do with Avi Loeb? In case you don’t know, Avi Loeb is a plasma physicist by training, whose former gig before moving to the astronomy department at Harvard was at the Institute for Advanced Study in Princeton — you know, the place where Einstein used to work. He’s authored more than a thousand papers and eight books; the guy is clearly no slouch in the science department.
And yet he has a habit of making statements about extraterrestrial life and technological civilizations that a lot of other scientists seem to chafe at, seeing them as sensational and attention-seeking. The criticism is understandable from an “extraordinary claims require extraordinary evidence” standpoint. When ‘Oumuamua streaked through the inner solar system in 2017, Loeb speculated that the chunk of cosmic debris could be a space probe from an extrasolar civilization, one designed to pick up signals from smaller probes sent to Earth at an earlier time, and that the smaller probes may be related to unidentified aerial phenomena (UAP).
Interstellar Coal Ash
More recently, Loeb and his colleagues mounted an expedition to the Pacific Ocean off Papua New Guinea to the impact site of a probable interstellar meteor, dubbed IM1, and recovered bits of it from the ocean floor. Isotopic analysis of the spherules revealed that some contained iron isotopes in different ratios than those found in the inner solar system, and some are older than the solar system itself, both of which support the meteor’s extrasolar origin. This is hardly conclusive, though; there’s evidence that the spherules are just coal fly ash from coal-fired steam vessels, but then again, Loeb’s further analysis of standard coal fly ash samples says they’re not.
Loeb doesn’t seem to directly state that the IM1 was a technological artifact from an extraterrestrial civilization, at least not that I could find — although he does a lot of interviews, so it’s quite likely he has. Regardless, the implication is that he thinks both IM1 and ‘Oumuamua are such objects, and that they justify a serious investigation into the nature of interstellar objects, to which end he co-founded the Galileo Project, an international search for physical evidence of extraterrestrial technical civilizations. And this is where we get to the cosmic lottery I think Avi Loeb is playing.
In a 2023 paper that gives an overview of the Galileo Project, Loeb and project co-founder Frank Laukien argue that the chance of finding a technological civilization at roughly the same level of development as ours in our neck of the galactic woods is pretty small, about one part in 100 million, which is the ratio between the age of our scientific society and the age of the oldest stars in our galaxy. So looking for technological signatures of an extant civilization is probably a fool’s errand, but it’s three times more likely than winning Powerball.
Five In a Billion (or Four)
What if a civilization like ours developed much earlier than we did? It’s possible that at some point in their development, they got the urge to explore their part of the galaxy and figured out how to fling stuff out into space, maybe zipping by the other planets of their system on their way into the void. It’s impossible to argue that such a thing couldn’t happen, since we’ve done it five times so far: both Pioneer probes, two Voyagers, and New Horizons, which isn’t in interstellar space yet but is on its way.
And here’s the important part: it only took our planet four billion years to evolve life that could manage the trick of sending stuff into interstellar space. The Milky Way is roughly 13.6 billion years old, so that means that if we assume the same rate of development, there’ve been over four full cycles of development scattered over perhaps 400 billion stars and at least that many planets. If only a small fraction of those planets got the interstellar itch and developed the means to scratch it, then the galaxy may be positively teeming with technological artifacts from long-dead civilizations. After all, our tiny little Voyager probes will be almost a tenth of the distance to the Andromeda galaxy in another four billion years, assuming they don’t run into anything on the way. If humanity could figure out how to amplify its footprint so dramatically in just two cycles of technological development, imagine what else is out there.
This is the galactic lottery I think Avi Loeb is playing. He knows that if we did it, then someone else probably did too, and he thinks the odds of finding evidence of that are very much in our favor if we just bother to look in the right place. As they say with the real lottery, “You can’t win if you don’t play,” and with a jackpot as big as this, Avi Loeb seems willing to buy tickets to the galactic lottery like crazy.
So why do people win the lottery if chances are slim?
Not sure the chances are that slim on the lottery. Evidence of teams buying sufficient tickets to always win exist such that the lotteries took measures to prevent that. I heard a hundred thousand “random” picks would be a net gain enterprise
Wat, how? That’s not how statistics work. You pay a fixed cost per ticket. If that price is higher than the possible winnings times the probability to win it’s a loosing proposition, regardless of the amount of tickets you buy.
Sure, you might get lucky and come out ahead, but in the majority of cases (that is to say, *on average*) you loose money.
It is dumb, but there are situations where it is statistically likely to profit.
It usually happens after a string of no-winner draws when the jackpot, and the corresponding partial winnings get insanely high.
Like, $300+ million.
The problem is bankrolling it, which will cost a bit over 1/3 of the jackpot.
It has been done by several groups in the past.
This is flawed unfortunately… believe me, I had the same thought a few times in my life. But this falls apart because multiple winning tickets can be sold- if there are 10 winners, your 300 million dollar jackpot becomes 30 million…
If you could reliably make money on a lottery, then lottery companies would go out of business. Instead they fix the odds, and the price of a ticket, so that they make money.
eg If a ticket is €1, and the prize is €1M, then the odds might be set at 1 in 1.1M, ie the lottery would take in €1.1M but only pay out €1M. If a syndicate tried to buy 1M tickets each week, over time they’d make about 90% of their ‘investment’ back. ie lose €100,000 each week.
(Made-up numbers obviously, and most lotteries have multiple prizes. In the UK the National Lottery pays out about 45% of the money they take each week)
It happens every now and again. Some lottery agency will screw up their math and people take them for all their worth. Then after a few months the game gets pulled or the odds changed. But not before they’ve lost millions.
Under normal conditions, sure.
But a lottery with a fixed ticket cost and a compounding jackpot can be a totally different thing if there are several rounds with no winner.
You should NOT buy a $5 ticket for a $20 million jackpot.
You SHOULD buy 25 million $5 tickets for a $300 million jackpot.
The chances of a SPECIFIC OUTCOME are minimal, not lending any hint or credit to what the numbers will be or the winner with matching ticket, if there is one; Instead, the chances that SOMEONE WILL WIN is always nearly 100%. Looking at historical data, there are two groups of math happening: The chances that you will accurately predict the full set of lotto numbers (1:23million or something like that on average) and the chances that AT LEAST ONE PERSON WILL CORRECTLY MATCH THE PULLED NUMBERS is much higher at around 94% per drawing. You can play your chances, but most people are reading the odds incredibly wrong.
Because a lottery is designed for somebody to win. It’s not an unfeeling, purposeless, emergent physical phenomena.
The universe was not designed for somebody to win. No requirement for this to even be possible.
A lottery is designed to make money by selling tickets. People winning is good publicity, but the odds are set that not *too* many people win.
“The Milky Way is roughly 13.6 billion years old, so that means that if we assume the same rate of development, there’ve been over four full cycles of development”
Probably not four, mainly because 4 times 4 is 16. You need several billion years to get the metallicity up, star size down, and calm the galactic nucleus. You could probably argue two.
Loeb’s basically trying to solve the Fermi Paradox via the “they have visited us” solution, but there are a number of other solid arguments you can make that end up with the “we’re the first.” Usually involves the rate of active astrophysical explosions (active nuclei, supernovae, gamma ray bursts, etc.) as well as metal production (which *rarely* gets mentioned in pop science-y type stuff).
I mean, look, we’re on a rare planet around a rare star in a rare section of the galaxy in a rare time in the Universe. Good chance several of those “rare” things are actually necessary.
>Good chance several of those “rare” things are actually necessary.
There I would have to disagree, as seen every time biology gets anywhere it isn’t cut and dry like pure mathematics where you can prove with pure logic the rules of math are consistent and there are within those rules exactly f(x) solutions. There were no antibiotic resistance bacteria etc until suddenly there are because even in the hostile environment they shouldn’t survive some very small probability events happen to find a way… So I’d suggest odds are very good there is or has been life out there somewhere in very different conditions.
It might even work out that all those rare things actually make life less probable, we will never know as the sample size of planets ever bearing live we know of so far is 1, and we won’t live long enough to change that (at least it doesn’t seem possible any time soon that we will ‘solve’ death or invent faster than light travel).
“every time biology gets anywhere it isn’t cut and dry”
Just disagree. It’s not hard to work out what the chance probability of antibiotic resistance is, and given the number of trials, it’s completely likely.
And the “life finds a way even in hostile environments” is really a bit of a myth: in the harshest areas on Earth, life *leaks in*, but it doesn’t really develop *on its own.* Antarctica is not green: there’s a limit to what life can do in extreme environments. Extremophiles basically survive by sheltering themselves, rather than adapting, because there are limits on what they can do, and they survive because the amount of life *right outside* their extreme environment is absurdly prolific.
“So I’d suggest odds are very good there is or has been life out there somewhere”
Yes, but that hits the Fermi paradox, because the Universe is just not *that* big. You can arbitrarily work your way around it by saying “maybe they don’t want to” or equivalent, but that’s a multiplier just like any of the “rare” situations I mentioned. Whereas if they actually *are* rare, they solve multiple things at once.
“It might even work out that all those rare things actually make life less probable”
I didn’t say “one of these rare things is necessary.” I said there’s a good chance of it. That’s the way statistics works: you increase the probability of life occurring on Earth (which we know is 1) if several of the “rare” probabilities are actually dependent on the others so they no longer multiply.
>I didn’t say “one of these rare things is necessary.” I said there’s a good chance of it
And I’m saying we can’t say that at all, as it stands we have a sample size of 1… For all we know the way life arose here and all the rare circumstances have only ever succeeded at making life this once despite many iterations. Yet an environment we currently believe is horribly hostile to life forming might actually be where almost all the alien life comes from and successfully produced life in 25% of occurrences… In which case the likely reason we don’t know about it already being space is really darn big, so noticing even a noisy next door neighbour is hard and we haven’t been around, making noise or listening for it very long at all…
That initial antibiotic resistance statistical analysis requires heaps of actual datapoints to create, and even then can with how noisy biology tends to be fails to look much like the real world results in many cases. But we don’t really have any datapoints for starting life at all, as if there was a god present they failed to leave a comprehensive and comprehensible experiment notes, and if no god existed it is chicken and egg – we can’t know only extrapolate rather wildly at the conditions of our egg, as no chicken was there to witness it for far too long.
“And I’m saying we can’t say that at all, as it stands we have a sample size of 1”
You can always say things even with a sample size of 1. What you say is just a reflection of your priors, that’s all. We *know* that we’re not a “typical” solar system, which automatically implies something about your “best guess” for what the likelihoods are. The uncertainties are huge, obviously, but that’s true with *anything* with limited statistics.
You could say you can’t say *with any significant confidence* that life is unlikely, but lack of confidence doesn’t prevent you from making a best guess.
I suggest that life does not (can not?) originate in those hostile environments. It adapts. Hot ocean floor vents, volcanic pools with pH levels and temperatures, high concentrations of salts and minerals, that demands very tough membranes all require adaptation from much more frail forms. Likewise adaptation due to competition and predation. Maybe it needs the kind of environment that can support a jellyfish.
You take the Fermi Paradox plus Von Neumann Machines and they should be everywhere. Unless the asteroid belt is from blowing up a planet to get the metals and build more VN machines which headed for other stars.
Yeah, the way I think about extremophiles situations is that it’s really just life “leaking in” from the favorable environments elsewhere. Humans are an example of that, for instance – we exist in space, but there’s no way we could’ve *evolved* there on our own – we are able to get there because there’s an extremely resource-rich environment nearby, so we “leak” from there into the (hostile) space environment.
Fermi paradox is easy: We already have, what, 8 different endemic respiratory diseases? Not counting variants. And counting. In virtually no time geologically speaking. The number of times we’ll get sick per year will keep increasing until humanity is too sick and unproductive to ever get off this rock.
Would aliens have disease? I can’t know but if I had to guess..
The paradox is even easier: have we ever, even once, seriously tried to send out a signal which would actually reach another star system and be picked up by an observer which didn’t know exactly what corner of the sky to watch at the exact moment we sent it? I’m talking an omni-directional signal which would be detectable over the noise of our sun.
Aricebo doesn’t count, it would have never made it even to the neighboring star in legible form and we only sent it once for a few minutes. “It was meant as a demonstration of human technological achievement, rather than a real attempt to enter into a conversation with extraterrestrials.” -Wikipedia
And no, episodes of I Love Lucy are not being watched seventy light-years away. They would have faded into absolutely nothing long before Proxima.
There was a plan drawn up on how do this for real in the 60s or 70s. As I recall in involved detonating H-bombs in Jupiter’s upper magnetosphere and using that as a giant amplifier and antenna to send information at whatever baud rate we could manage in nukes-per-second. That might barely break into a legible SnR in another star system. Barely.
Did we ever seriously attempt that? Even once? No. It’s too expensive. Why do we think other species are bankrupting entire civilizations just to shout out into the dark? We aren’t, they aren’t. No paradox.
It may also not be a good idea… broadcasting our location to possibly hostile species may be detrimental to our survival. Read “the hunter in the forest” chapter in the Three Body Problem trilogy.
We’ve already done it. I have no idea why people focus on radio emissions when we’ve been screwing with our atmosphere for 100 years in flamingly obvious ways and light is easier to focus than radio. The existence of life is flamingly obvious due to the oxygen content, and technological signatures are detectable as well (CFCs mainly).
“have we ever, even once, seriously tried to send out a signal”
Yes. Although it wasn’t us. Plants mostly did it, in combination with the Sun. Earth’s atmosphere is a giant glaring beacon that there’s life here. We’ve actually done quite a bit recently, too, thanks to our lovely flirtation with CFCs.
Could we do this now with Earth from interstellar distance? Probably, but not very far, and there aren’t really any single Sun-like stars to study in that distance. There are missions currently planned to be able to do it, though. It’s definitely technically feasible out to distances of hundreds of light years, and the entire point of the Fermi paradox is that given the absurd timescales of the Universe, it’s not *that* hard to colonize the galaxy technologically.
“…the chance of finding a technological civilization at roughly the same level of development as ours in our neck of the galactic woods is pretty small, about one part in 100 million, which…”
I call BS. At present, there is ZERO probability of finding other life, let alone civilization, because to date there is ZERO objective evidence for extraterrestrial life at all…and no plausible mechanism for it’s spontaneous generation. Our planet represents a sample of ONE, and we dont even understand that.
The “universe is very old/large” argument–a wild card, woefully over-played–doesn’t fly either. The odds of a soup of amino acids randomly assembling into a single useful protein, for example, ( which already presumes chemical conditions that would never naturally occur on any proto planet) are less than the odds of you shooting an arrow into space and striking a single, previously marked electron. And even if you pulled that off… that’s one protein, nothing remotely alive.
I’m open-minded. I look forward to +verified+ discovery of other life. (Given the methane cycles on Mars, there may well be microbial life there, for example, and we should search for it.) But until that day comes, the Sagan-esque narrative of a universe “teaming with life” is a fairy tale with no place in real science.
The argument cuts both ways, I guess.
On the one hand, the argument goes that there is nothing special about Earth and life developed through chance operation of random processes; there are a hundred billion other stars in the galaxy and so even if the chances of life developing on one in four billion years is only the same as winning the powerball, we should still expect it to happen maybe ten times in the life of the galaxy.
On the other hand, we’ve been looking for a while now, and have found no evidence of it whatsoever. So maybe the development of life through random processes operating randomly isn’t as likely as we thought?
If you estimate life to happen once in a 100 million, and you consider that we have already happened, then the chance of finding someone else in the same place must account for the fact that we’re already here.
So it would stand to reason to argue that finding other life besides us around the same part of the galaxy is about 1 per 100 million squared, or 1 part in 10^16.
isn’t that the gambler’s fallacy? Our existence doesn’t discount the possibility of others, we don’t suck the luck out of the surrounding area
Not really.
Think of it like this: you have two dice under two cups and you shake both cups. Then you lift one cup and find it’s a six. What are the chances that both dice are six? Since both cups were already shaken, the chances are 1/36 regardless of whether you peek under one cup first.
If you were to shake the second cup again, then the chances would be 1/6 and the gambler’s fallacy could apply. However, the universe isn’t re-shuffling the odds of someone else being here with us while we’re not looking. They either are or they’re not – by the same original draw of luck.
No, that’s still the gambler’s fallacy. If life happens once in 100 million, we *already know* that we’re a 1 in 100 million case. The chance of life appearing elsewhere in the same galaxy is still 1 in 100 million, not 1E-16, because we *already are* the 1E-8 case.
The 1E-16 case would apply if you were surveying galaxies looking for 2. Doesn’t change the probabilities in *our own* galaxy because we’re already contingent.
So what that’s saying is, considering we’re already here refers to accounting for the initial odds of anyone being here at all. After all, even if we assume there’s someone else here already, we might have ended up anywhere else.
> If life happens once in 100 million, we *already know* that we’re a 1 in 100 million case.
Yes, but that’s not saying anything about whether we had to end up in the same place as someone else. If the chances of us ending up here is 1 in 100 million, and the chances of someone else ending up here is 1 in 100 million, then the chances of us both ending up here at the same time is P*P.
>The chance of life appearing elsewhere in the same galaxy
Note that we’re not asking that, but whether someone else is HERE in the same neighborhood where they can reach us and vice versa. It’s a moot point if they’re all the way across the other side so we would never discover one another.
Yes. He sets up the Monty Hall problem then answers it incorrectly.
“Yes, but that’s not saying anything about whether we had to end up in the same place as someone else.”
If you assume the chance of life in a galaxy is 1E-8, the chance of us landing the same place as anyone else is (drum roll) still 1E-8.
Some people have done some effort to get a recognisable radio signal with a pattern that seems unnatural.
I would not classify that as a general ‘we’ve been looking’
Nor would I conclude from failure of results from that that there is a complete absence of intelligent life in the universe, that seems a bit overdoing it.
It seems in general rather hard to find things, I mean for instance the IDF are in the air over a small patch of land and cannot find rocket launch sites, even when thousands of rockets are fired.
Same for people that go missing hiking right in the US and can’t be found with any ammount of effort.
They could also not find trace that giant malaysian airliner that went missing regardless of how much effort they did.
And we would be able to find tiny probes in freaking infinite space? I think not really.
And regardless how they present it in the news we can’t really see exoplanets, we can see dips in lights of stars and can get some spikes in the light spectrum allowing us to somewhat infer a chemical makeup from the difference, but that’s about it, and that data is probably not all that precise in most cases either.
“And regardless how they present it in the news we can’t really see exoplanets”
No, we have directly imaged some exoplanets, and one of the strong recommendations of the 2020 decadal survey was to prioritize a design for a larger telescope to do direct imaging as well. The most obvious example is HR 8799, showing the 4 exoplanets orbiting over a 7-year period.
Obviously there have been more detected by transients or radial velocity techniques, but that’s just because there are obviously far more stars far away from us. The next generation of space telescopes (as mentioned before) target being able to directly image Earth-scale planets up to about ~500 ly or so.
The largest ones studied (LUVOIR) would be capable of mapping out surface reflectivity enough that you could get a rough land fraction map for rotating planets. Once you get spectroscopy you can do a *ton* more than “somewhat infer a chemical makeup.”
>> “there is ZERO objective evidence for extraterrestrial life at all…and no
>> plausible mechanism for it’s spontaneous generation. ”
And yet, here we are.
Truly a paradox.
https://youtu.be/k_B9YP5nEWw
Indeed.
https://www.youtube.com/watch?v=AjTEKPonnYo&t=2514s
And at 42:52 is a good analogy.
Also…
>> “Our planet represents a sample of ONE, and we don’t even understand that.”
So… number of reasonably temperate, wet, planets we’ve thoroughly explored == 1
Number of places we’ve found life after thorough exploration == 1
Ways that the explored example seems particularly unique == 0.
Implied hit rate == 100%
Are bowling balls heavy? Well, If you had some idea of how bowling balls work, but you’re only able to examine one apparently typical bowling ball, you would be pretty secure that the answer was more likely “probabably yes” instead of “probably not”
“Ways that the explored example seems particularly unique == 0”
Huh? Where did *that* come from? The number of anthropic coincidences involved with Earth are fairly absurd. We orbit a rare star in a rare orbit in a rare configuration in a rare region of space at a rare point in the Universe.
We’ve found exactly 1 other planet (Kepler-452b) that hits most of those ‘rares’, except it’s old enough that there’s a good chance it’s dead already given what we know about Earth.
>> We’ve found exactly 1 other planet …
Operative words: “We have found…”
The amount of “Eh, nothing special here” very closely tracks our ability to actually examine the heavens. Like much of the “We’re unique argument” It mostly seems to be a measurement problem. Every time our tools let us step down one level we find the exact same stuff that we have here.
We found Kepler-452b almost immediately after we were finally able to discriminate something as small and distant as Kepler-452b.
This has been the pattern for the last 1000 years.
We are the only planet!
Nope. Here’s a telescope. See, those bright dots are planets too.
We have the only sun!
Nope. Here’s a bigger telescope. See, the other stars are suns too.
Ours is the only Galaxy!
Nope. Here’s a *bigger* telescope. See, that Andromeda blob is whole other galaxy.
Ours is the only planetary system!
Nope. Here’s a radio telescope that sees a disk around PSR 1257.
But you don’t have an actual picture!
Yeah, These guys used a big array in Hawaii to photograph a timelapse of the system HR8799
But you can’t verify the chemistry!
There’s a spectroscope on Webb, and….
“We found Kepler-452b almost immediately after we were finally able to discriminate something as small and distant as Kepler-452b.”
I didn’t list Kepler-452b because the fact that we’ve only found “one” is important – I listed it as “one” because we’ve found over 4000 *other* exoplanet systems. And it’s not really an observation bias because the reason there are so many *others* is because there are just *that many more* other kinds of star systems.
I’m just pointing out that no matter what, Earth is definitely not a “common” planet. It’s just a question of how rare, not whether or not it’s rare.
>> ” I listed it as “one” because we’ve found over 4000 *other* exoplanet systems.”
I think I’m making my point poorly.
What I’m trying to say is that the fact that we have 4000 gas giants and only one 452b probably has as much to do with our sheer inability to image tiny rocky planets as it has to do with their scarcity.
If I fly over a spot in Africa and take an aerial photo juuuust good enough to verify 4000 elephants it still doesn’t tell me anything about how many meerkats there are. it only tells me that there are at least 4000 elephants.
And if I’m lucky enough to get one picture juuuust good enough to see one meetkat den when the conditions were absolutely perfect, it doesn’t tell me that there’s only one meerkat out there. Especially if I’m at the very ragged edge of what my camera can do, it only tells me there’s _at least_ one.
But if I know, based on my time in Johannesburg, that elephants and meerkats seem to be found in the same environment, then those 4000 elephants I *do* know about become important clues to the existence of lots of meerkats.
No, sorry, I think you’re still misunderstanding my point. You’re absolutely correct that there’s observation bias in our exoplanet observations.
But that’s not the sole reason why we’ve found so many more planets around M stars. It’s some of it, yes, but the majority of the reason is just that there are *so many more M stars out there* – and there just aren’t that many solo F/G/K systems nearby.
I mean, just to make it clear, there are mission studies out there to build wacko-huge space telescopes (~10+ m) to directly image terrestrial planets within ~150 pc. The science goal for “success” is 1 Earth-size planet in the habitable zone around an F/G/K star. One. That’s the statistics you’re talking about (if your thought is “but it’s still more than zero” see below).
Planet formation is common – that part we know. But we also know that the Sun is *not* common, and we’ve known that for years. If you say “life can only form around solo Sun-type stars” for whatever reason, you’ve already cut down the number of stars by a factor of 100. If you say “life can only form beyond ~10 kpc from galactic center” that’s a factor of 1000 or more.
To be clear: None of this cuts the number low enough so that you wouldn’t guess *just from this* there’s still a *lot* of planets with life, but that’s just the start. I’m not saying that any of this *proves* that Earth is unique, but just from “star type” and “location” you’re well on the way to “extremely uncommon,” and there are plenty of other “weird” factors about Earth and our solar system (for instance, the roughly ordered mass distribution).
I should also note that we’re starting to get past the ‘observation bias’ point now as well since we have enough data to start picking up information about planetary system *formation* rather than just independent planets. As in, yes, sure, we can’t easily detect small planets far out from a star… but we actually don’t quite *need* to.
Because it turns out that just detecting *a few* planets in a system is almost enough to tell you how many total planets there are, because the more planets a system has, the lower the total eccentricity of the entire system. The more planets you have, the more planet-planet interactions that tend to circularize orbits.
So, for instance, if you say “well, life can’t form outside of a system with a high number of planets” and you have a system where you’ve detected 2 and they’re both high-eccentricity… it doesn’t matter that you wouldn’t be able to detect others, because they very very likely *aren’t there.*
And yes, as you might guess, the Solar System is in fact a strong outlier (1% at least) in that the average planet eccentricities are stupidly low (meaning a large number of planets).
Weak anthropic principle. Analysis voided.
Well, there is zero evidence for … yeah, aliens.
But that second part is like, straight from creationists … oh, sorry, cdesign proponentsists, texts.
Proteins do not form randomly from amino acids but by step-by-step process.
And when you dismissed possibility of “correct” chemical conditions occurring naturally, what do you propose? Something unnatural?
> “that second part is like, straight from creationists”
+1
Those are same arguments my highly religious high school physics teacher made to try to “prove” that a powerful sky fairy created life on earth.
Any person who argues that a sufficiently large universe plus a sufficiently old universe automatically results in life IS, by definition arguing spontaneous generation.
Yours is not an argument against the “sky fairy”… it’s simply an argument for a different sky fairy.
Erm, no…. At no point did I bring any “argument against the ‘sky fairy'”, I’ve just re-enforced that the argument presented is the same as those used by creationists (and my experience of its deployment was rather deceitful).
Although your comment implies you can’t accept the idea that life can occur naturally without the intervention of a divine being? Sorry, I don’t believe magic was involved here….
Ultimately I am fine if you want to believe in that stuff, right up until the point you start creating laws limiting what I am allowed to believe, say and do because of your imaginary friend.
That’s stupid, it’s not a creationist argument by a long shot. It is just the sober reality that we only have a data set of 1, and thus any extrapolations are so unreliable that they should be treated as fantasy.
“Is there life out there?” -Almost certainly yes. We are out here, after all.
“The chances of life are bla bla 100 million to seven bla bla bla” -Absolute nonsense made-up on the spot, there are no ways to know specifics for us at this moment.
That we have data set of 1 and chances of life are X is just a guess is not a creationist part.
The part about amino acids randomly assembling full protein by chance and “unnatural” chemical environment is creationist part.
And “spontaneous generation” did not help either.
“…And when you dismissed possibility of “correct” chemical conditions occurring naturally, what do you propose? Something unnatural?…”
Not proposing anything, just stating fact.
Proteins are comprised of chains of amino acids…in even simple cases, hundreds of them. Proteins are not homogeneous like a cake, where altering the ingredients still results in a cake, but with slightly different flavor. Rather, they rely on their folded shape to function, which means the amino acids must be in a precise sequence to be functional/viable… not unlike letters, in proper sequence, to form an intelligible word.
Furthermore, amino acids have no identifiable chemical proclivity to assemble in any preferential way….like the dice in a Boggle game. Shake ’em up and lay ’em out and you’re as likely to spell “jqx” as “yes”. Like the Boggle letters, only a fraction of possible amino acid sequences–even in short chains—have been found to have potentially viable function.
The acids are linked by peptide bonds, which occur only half the time, and all known functional proteins are built from left-handed molecules.
What that means is that even under chemical circumstances rife with amino acids and an environment conducive to assembly (not likely given probable conditions on a sterile infant planet) randomness begets randomness, not functional design– at least not with sufficient frequency to account for spontaneously-generated life.
By the way, my remarks concern the probability of self-assembly of a single unalive protein. They don’t even acknowledge the big elephant in the origin-of-life room…how an information-bearing structure like DNA can arise from randomness.
The old trope about a million chimps on a million typewriters for a million years writing Shakespeare is amusing, but nobody with any material understanding of basic math would ever take it seriously.
So what accounts for life? The +scientific+ answer is we simply
don’t know.
But won’t a randomly-assembled replicating amino acid chain start to “consume” all the free amino acids around it, converting them into the replicating chain? Given a shedload of time.
Then throw in replication errors, and gradual survival of the fittest chains.
Surely we now have enough computer power to simulate that?
Not really. Simulating organic molecules is a freaking disaster even without adding in externalities like a medium plus other resources/etc. You’re essentially taking the protein folding problem and amplifying it. (Not that people haven’t tried, mind you, if you simplify things and make assumptions, you can start to do it).
But the problem with the “replicating is lowest energy” argument is that your resource pool needs to be big enough that you don’t, well… consume everything and die. Competition only works when there’s a wide variety of options. The biosphere’s big and complicated enough on Earth to avoid that, but when you’re starting out, you have to be both simultaneously fast enough to replicate on reasonable timescales and *slow* enough to not empty the planet. This is part of the reason why I’m not a big fan of the “well there might be a pocket of water” arguments for life on desolate planets.
Yeah, all these calculations are built on fanciful assumptions, and they aren’t worth a damn thing. Like the Fermi “paradox” or Drake “equation” they are pure BS. Not a single bit of data in the whole stack. Writing science fiction would be a lot more honest and entertaining.
Note the common Sagan quote “extraordinary claims require extraordinary evidence”. This not and never has been true. Most extraordinary claims have had obvious evidence that was misinterpreted or disregarded. He so often made statements like this. He wasn’t stupid. I think he just liked the sound and played the odds that some of his stuff would be true. That is how he did predictions about the planets, and watched as probes sent images “Look! Just as I predicted!” A good gig if you can get it.
+1. Exactly right. The dreamy Sagan (known for having the best dope on campus) and Drake Equation nonsense permeates the popular view and that of so many high school and astronomy teachers and general science enthusiasts. Just because you did a lot of calculating to come up with a number does not make it interesting.
No one yet knows how to get a molecule that can duplicate itself and NOT be ruined by binding adding another atom or molecule. One really needs to know how this happens and in what conditions in order to start working on probabilities.
>but it’s three times more likely than winning Powerball.
If you want to compare improbable events, consider that 20 million powerball tickets are bought each draw, so the odds of someone winning is about 1:150 – and you have three draws a week 52 weeks a year for a total of 156 chances to win it. You would expect about one jackpot every year just by the sheer number of tickets sold.
Meanwhile, finding another technological civilization in our neck of the woods is like having just one Powerball draw in the entire history of the universe, and buying three tickets for the draw.
Still wanna bet on it?
And when the jackpot goes high, so does the number of tickets sold. There were 62.9 million tickets sold on the last draw of 2023, which puts the odds above 1:5.
Using lottery jackpots for perspective on astronomically improbable events is wishful thinking in like proportion.
Here in the UK, the lotteries are a bit different, the jackpot is rolled over a set number of times and if it’s not won then it’s used to make the lesser prizes larger.
It’s still a mug’s game, but, I also subscribe to the ‘the chance isn’t zero’ option and as a portion of the cash goes to charity anyway, it’s a little more palatable than gambling it away on horse racing or something.
It’s also the desperate person’s game.
If you’re stuck in a dead end situation where your options are to die penniless or bet on improbable odds, then it makes sense to gamble. If you don’t win, you’ll die penniless a little bit sooner, which is an improvement on the case.
It’s a way of giving a class of people hope so they don’t start figuring out where the people with the big money live
I’ve nothing to contribute to the probablistic speculations here, but am compelled to point out that “our tiny little Voyager probes will be almost a tenth of the distance to the Andromeda galaxy in another four billion years” isn’t possible: they have only a tiny fraction of the escape velocity of the Milky Way galaxy.
No, those puny human-child toys are condemned to wander the local neighborhood until they either hit something or just evaporate away.
Though there’s still a chance one might win the lottery and encounter a binary black hole and get slingshotted out at near light speed…
“they have only a tiny fraction of the escape velocity of the Milky Way galaxy.”
What makes you think you need the escape velocity of the Milky Way to reach Andromeda? *Andromeda* doesn’t have the escape velocity of the Milky Way!
Considering the Andromeda galaxy is on track to collide with the Milky Way in 4.5 billion years, the statistic of being a tenth of the distance to Andromeda in four billion is significantly less impressive.
“*Andromeda* doesn’t have the escape velocity of the Milky Way!”
True enough. At 25 milky way diameters away, it’s roughly equivalent to the distance of the moon from earth. To get to the moon requires about 96% of the earth escape velocity. I have not done the calculation for Andromeda, but (dark matter notwithstanding), similar physics would apply.
A “tiny fraction of escape velocity” is still “a tiny fraction of 96% of escape velocity”.
“I have not done the calculation for Andromeda”
See TG’s response: the reason I said Andromeda doesn’t have escape velocity is that the two galaxies are, in fact, colliding. Voyager’s definitely getting to Andromeda one way or another (and so are we).
I imagine the chances of a civilization getting destroyed by a big rock is statistically higher than the chances of them developing true interstellar travel capabilities.
I view the lottery as a ticket to dream. I think deep down most people do.
“humans amplify their footprint”
Cool. Say the Romulans.
Implying it’s a sign of another civilization is a jump. Let’s be happy that we got interstellar meteoric iron. If it looks like steel then we’re onto something
Avi Loeb’s blog is an interesting read, and sheds some more light on the situation.
The spheres contain iron but no nickel. Iron and nickel are formed together and there’s no known astrophysical process that would separate the two, but an advanced civilization would separate iron from nickel to make steel. If you posit that the spheres had a natural origin, you also need to posit the natural process that would do the separation.
As to coal ash, he dragged the sea floor with essentially a sled lined with magnets. He finds the spheres on the path of the meteor (as predicted by NASA), but no spheres in areas outside the path. It’s highly unlikely that some ship burning coal came through the same area in a way that would spoof the experiment, and not be part of some trade route that would show spheres everywhere.
In the same manner, spheres from a volcanic eruption would be spread over a wide area, and again he found none in areas outside the meteorite path.
But doing the experiment (comparing coal ash to the spheres) was good – it completely eliminated that explanation.
Avi Loeb has a lot more information about the whole trip on his blog, and the parts about this are especially interesting.
https://avi-loeb.medium.com/
> there’s no known astrophysical process that would separate the two
But then, “native iron” has been found on earth at least in Cameron, Missouri, USA and elsewhere. How did it get there? Constraining the process to be only “astrophysical” discounts the fact that such iron may come from geophysical processes here on earth, and from other planetary bodies where it was subjected to similar processes before it was flung out into space.
https://rruff.geo.arizona.edu/doclib/hom/iron.pdf
Also, can you dig up the claim about “no nickel”? What counts as having no nickel?
https://en.wikipedia.org/wiki/Telluric_iron
Telluric iron can have nickel content down to 0.05% and come in “pea-sized droplets that crystallized with a mostly spherical or oblong shape” and one source I can find indicates some deposits with no measurable nickel at all.
And, if one were to make steel for space applications, one would ADD nickel to iron because it’s an important constituent of stainless steel and makes the material ductile at very low temperatures. Without the nickel, it would be difficult to form and weld the steel, and it would be brittle against impacts. If it was an object of technology, one would expect around 10% of nickel instead of none.
For example, a common grade 304 austenitic stainless steel used in cryogenic applications contains 9% nickel, and heat resistant grades (600+C) such as 309 contain 10% or more. Ferritic stainless steels in turn are completely unsuitable for cryogenic applications and one wouldn’t use them in space applications, and while martensitic stainless may not contain nickel, the aerospace martensitic alloys do.
Common structural steels also employ nickel, although typically in lower amounts under 1%
https://www.mdpi.com/2674-063X/2/1/1
The idea that a technological civilization would make a spacecraft with steel but no nickel doesn’t appear to make sense.
>If you posit that the spheres had a natural origin, you also need to posit the natural process that would do the separation.
Or simply to observe that:
“Telluric iron resembles meteoric iron, in that it contains both a significant amount of nickel and Widmanstatten structures. However, telluric iron typically contains only around 3% nickel, which is too low for meteorites, of which none have been found with less than 5%.”
Clearly there IS a natural process that separates the two and can result in very low nickel content, here on earth, so why not elsewhere? That alone suggests that the iron is more likely from earth in the first place, unless you fall on Occam’s Razor by claiming that the telluric iron on earth was left here by aliens, which would be begging the question.
“He’s authored more than a thousand papers”.
In academia, this is typically a massive red flag.
Yeah this is piffle
Regarding lotteries, at least those that roll over if nobody wins: There are hypothetical situations where the “best bet” is to play. For example, if the odds of winning are 1 in a billion and tickets cost only $1, you can spend $1B for a guaranteed winning ticket. The “gotcha” is that you MIGHT have to share it with someone. However, if there is already $1B in the pot and nobody else plays, you’ll get $2B minus what the house takes and what the tax-man takes. If that happens to be more than $1B and your time costs you nothing (NOT TRUE!), then it’s a smart move to spend the $1B, provided you can be 100% sure nobody else is playing.
The point of “the next drawing is a smart bet” is hardly ever reached though: As the “pot” goes up in size, more people “come off the sidelines” and bet, making it much less likely that the next draw will be anything other than “not a good bet.”
Which is where the metaphor breaks down: the difference between a lottery and interstellar travel is that in the latter case, nobody is required to “win.” There is no evidence anybody is even playing.
Here:
-Interstellar travel isn’t going to happen. Probably not with robots. Definitely not with live subjects. Sorry. It’s just not. “But but—” No. Not even with Alcubierre or whatever, not with emdrive, not happening. In a million years. In a billion. Yes, there is other life out there. Older life, more advanced life. But no, they are not going to neighboring stars.
-Nobody is ever ever ever ever going to find the Voyager probe. Even if there were a technological civilization on the third planet of every single star in the sky, nobody would find it. Ever. It is purely symbolic. We would never find it ourselves if we didn’t already know exactly where it is. And it’s in our own backyard.
-Oumuamua was a rock.
There is no paradox, it’s just an illusion caused by not really understanding such distances. This guy is playing around with numbers in complete absence of data (like most of the absolutely useless Drake equation) and it doesn’t really mean much. I think his colleagues are right, he’s obviously an attention-seeker.
>Interstellar travel isn’t going to happen. Probably not with robots. Definitely not with live subjects. Sorry.
I’d have to disagree, it isn’t likely to happen here any time soon is very true. But as we just don’t know enough of how the universe works to prove things like FTL are impossible. Or to prove that all lifeforms can’t possibly go dormant and hibernate their way across millennia of slow crawl through space. Or that an old very humanlike civilisation won’t even try to migrate as their solar system runs out of resources they want, it’s star reaches EOL etc.
>Nobody is ever ever ever ever going to find the Voyager probe.
Very probably, but then odds of winning the lottery etc are so very long but it happens. If such a thing from a neighbour made it here there is a very much above zero chance it could be captured and stay in the solar system, at which point the odds we will spot it eventually go up a great deal, and a very slim approaching zero chance it will crash into something in a way we can’t miss it at all…
>Oumuamua was a rock.
Perhaps, even probably. But it certainly does seem to have been a very odd rock by all accounts. Not that our species has been observing and documenting such things long enough to draw any real conclusions.
> in complete absence of data
very nearly true, there is very little data. But that works both ways – can’t prove or disprove anything with next to no data. So being curious and open minded isn’t a bad thing – it is in part why you end up with there being actual data and experiments done…
https://youtu.be/m3QJDcwxDrI
“Tolman’s Paradox”
You can disprove anything with a single counter-example.
“Artifacts of an advanced civilization” – I wonder what kind of civilization artifact can survive billion years and be recognizable. Even 1 million might be quite difficult.
We have billion year old rocks and know what they were and how they were produced.
No, this is a harder problem than you might think – sci-fi shows often just pretend you can magically date just about anything, but that’s very unrealistic.
We date things generally by radioactive dating, but that requires either a cycle or a known point in time you can identify so you can lock onto an initial isotope fraction. Carbon dating, for instance, is based on the fact that living objects cycle carbon and the carbon-14 fraction in the atmosphere is roughly constant due to being produced by cosmic ray interactions. Rock dating the solar system is generally based on some sort of ratiometric dating where they find the *initial* fraction by looking for meteorites with the least amount of radiogenic nuclei to get the original point. There are other methods as well (for instance, helioseismology can date stars since it essentially measures nuclear burning).
Something that’s artificially produced could be very hard to identify or date, hence the problem at hand. Generally it’s basically all going to be via isotopic ratios, but barring the use of something obvious it wouldn’t be very easy.
https://youtu.be/vyEWLhOfLgQ
“Silurian Hypothesis”
Andromeda is 2.5 million light years from Earth and objects observed in the night sky no longer are where we view them today; in fact, they may not even exist. Consider that our Solar System is in constant motion and makes 1 revolution around the Milky Way every 250 million years.
Even if a transmitting station could achieve the focused power necessary to reach Andromeda, trying to hit a moving target while on a carousel seems to be a near impossibility. An interesting Thought Experiment with 0% probability with current technology; The odds of winning the lottery are > 0.
Looking out on the night sky is viewing history from long, long ago. Our machines paint wondrously beautiful pictures of what was, but we are most likely never to know what is. With all of the problems on the speck of dust called Earth, humans should best turn their attention and effort inwards as the stars will not save us from ourselves.
https://www.youtube.com/watch?v=aY985qzn7oI
Do we really want to announce our existence to other intelligent life elsewhere in the universe. Evidence in our world suggests life consumes, then moves on Mankind did not treat less advanced civilizations well. “Welcome to Earth! We are belligerent but tender!”
“Do we really want to announce our existence to other intelligent life elsewhere”
We’ve been doing that ever since we started pumping short lived chemicals into the atmosphere. Humans would have to do a *lot* of back-tracking technologically to get back to undetectable.
Bwahaha, so apparently whatever Loeb’s team pulled up isn’t alien… or at least it didn’t come from that meteor, because the only reason they thought it was there was signals from a seismometer that turned out to be… a truck.