Are We Alone In the Universe? Not Likely, According To Math (cnet.com)

An anonymous reader writes: An equation, which calculates the probability of the evolution of other technological civilizations, has found that it's wildly unlikely we're the only time advanced society in the universe. Adam Frank from the University of Rochester and Woodruff Sullivan from the University of Washington base their new equation on the Drake equation, used for calculating the probability of extraterrestrial civilisation, written by astronomer and astrophysicist Frank Drake in 1961. The scientists also take into account Kepler, which suggests that one in five stars have planets in the habitable zone. Frank and Sullivan calculated that human civilisation is only unique if the odds of a civilisation developing on a habitable planet are less than one in 10 billion trillion. "One in 10 billion trillion is incredibly small. To me, this implies that other intelligent, technology producing species very likely have evolved before us," Frank said. Frank said: "Of course, we have no idea how likely it is that an intelligent technological species will evolve on a given habitable planet. But using our method we can tell exactly how low that probability would have to be for us to be the ONLY civilization the Universe has produced. We call that the pessimism line. If the actual probability is greater than the pessimism line, then a technological species and civilization has likely happened before."

Comments

It's wildly unlikely we should exist

[freak0fnature]

given how complex we are...

Re:It's wildly unlikely we should exist

[Dunbal]

it's almost as if someone intelligent designed us....

incoming shitstorm

Seriously, we're not that complex. A few billion years is an incredible amount of time.

Re:It's wildly unlikely we should exist

[khasim]

But the UNIVERSE is huge. With billions of galaxies. And each galaxy has billions of star systems.

The question isn't whether we are the only planet where life evolved.

The question is whether any other life will ever be able to contact us.

The universe could have a million planets with intelligent life. And not one of them within a million light years of another.

Re:It's wildly unlikely we should exist

[theIsovist]

We might not be that complex, but we're still outside of the norm. Which means that even though the total number of beings like us might be numerous, it's still rare. To quote Douglas Adams who does a much better job of describing this:

“It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds. Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero. From this it follows that the population of the whole Universe is also zero, and that any people you may meet from time to time are merely the products of a deranged imagination.”

Re:It's wildly unlikely we should exist

[jellomizer]

Well the fact that the universe seems to have limited matter vs infinite void. Means that there is 0% chance that matter exists in the universe. However there is...

While I am not going to say that there was an intelligence behind it. However if the universe is limited in size, there seems to be a contradiction in the nature of the universe.

Re:It's wildly unlikely we should exist

[Dunbal]

How are we outside the norm? Given the size of the universe, the handful of planets we've managed to examine so far can't be considered anywhere near being a representative sample. Who are you to say what the "norm" is? I appreciate the Hitchhiker quote, btw. Just saying - the "norm" might not be what we think it is.

Re:It's wildly unlikely we should exist

[MightyMartian]

One may argue that we are outside the norm for life on Earth; although i'd argue that there are enough other species that show some degree of sentience; members of genus Corvus, the other great apes, cetaceans, and even elephants, that I'd argue that we are more the most extreme example of a phenomenon found in several lineages, in particular in mammals (though genus Corvus are birds). The differences are more degree. Obviously that matters, because there are no chimps building skyscrapers or writing posts on Slashdot, but it also means that our cognitive abilities are firmly entrenched in evolutionary processes.

There's no reason to imagine that if Earth alone can produce two or three lineages of animals capable of some degree of sentience that there aren't millions of worlds in the vastness of the Universe that haven't produced similar organisms.

Re:It's wildly unlikely we should exist

[MightyMartian]

I think the only contradictions here derive from your assumptions about the nature of the universe. In other words, you have created the issue yourself.

Re:It's wildly unlikely we should exist

[SJHillman]

Don't confuse the Universe with the Observable Universe. The Observable Universe is not infinite. The Universe may well be.

Re:It's wildly unlikely we should exist

[ShanghaiBill]

But the UNIVERSE is huge. With billions of galaxies.

Sure, but it is unlikely we will ever make contact with life outside our own galaxy. So the real question isn't whether there is other life in the Universe, but whether there is other life in the Milky Way, where civilizations can spread from star to star until they eventually meet.

Re:It's wildly unlikely we should exist

[Empiric]

Very.

Provide a counter-demonstration and whip up a sentient AI.

As this discussion rapidly devolves into the standard "you can't define rigorously the term 'complex', therefore even though both of us are perfectly clear what it is, you have no point I'll acknowledge until then" intellectual dishonesty, I'll pass on further followup--for now.

Re:It's wildly unlikely we should exist

[Dunbal]

One may argue that we are outside the norm for life on Earth

Not trolling - merely a friendly discussion:

Of course there are different TYPES of intelligence too. I like to think that every single being that is alive on this world today is a survivor - it and its ancestors have survived in an unbroken chain all the way back to that first cell. Just that fact alone is a phenomenal accomplishment. And when you look at any creature, even say a colony of ants - well they didn't invent calculus nor do they write poetry, but they are intelligent enough for their niche - they can adapt and they can survive. Sure we have what we call sentience. We like to think we're the "most" intelligent on this world. But our very survival is in question. War. Overpopulation. Pollution. Pick one. How smart were we, really, if we won't even exist anymore in a million years?

Re:It's wildly unlikely we should exist

[SJHillman]

There's one significant flaw in that reasoning. If we assume there are infinite planets, and only a tiny subset of them are inhabited, that subset does not need to be finite... it can still be infinite.

Consider integers. There are an infinite number of integers. One subset of that is odd numbers. If we subtract an infinite set (odds) from an infinite set (integers), the remainder can still be an infinitely large set (even numbers).

Re:It's wildly unlikely we should exist

[dmomo]

>Therefore, there must be a finite number of inhabited worlds.
This logic is actually flawed. You can have two infinite groups where one is a subset of the other.
It's the equivalent of this faulty argument:

There are an infinite number of integers. However, not every one of them is a natural number. Therefore, there must be a finite number of natural numbers.

Re:It's wildly unlikely we should exist

[Sparowl]

That's not mathematically sound. If there are infinite number of world, then saying that not everyone is inhabited does not reduce the number of world to a finite number. It could still easily be infinite number of world, with an infinite number of inhabited ones.

Infinity is a difficult to understand concept for many people.

Re:It's wildly unlikely we should exist

[MightyMartian]

Intelligence is one solution to the problem; a solution that has been used by a lot of species since the first nerve fibers joined together to form a primitive ganglion. But it's hardly the only solution. In sheer biomass, E. coli has all the multicellular animals with brains beat, because its solution to the problem of survival is to reproduce very frequently. In reality, that works really well, which is why most of the life on Earth is in fact prokaryotes. All the eukaryotes are just sort of an icing on the cake, and a rather thin frosting at that.

Re:It's wildly unlikely we should exist

[Muros]

there are no chimps building skyscrapers or writing posts on Slashdot

You must be new around here.

Re:It's wildly unlikely we should exist

[MightyMartian]

Let me amend that. There are not a lot of chimps posting on /.

Re:It's wildly unlikely we should exist

[serviscope_minor]

It's also wildly unlikely that I got these numbers out of /dev/random (base64 encoded):

a2yIbR 06VMDu f3WkRu mCTMwT S/1sTr 5MC+JF VIAYQo El1/dj WPL+JL HNUZSZ 0yTnsd UDstFc SwIQcZRCTZ MXVO1o cqvrbG vn1TF4 qKhdL4 mBsdiI BxZ4Sx 9P+Pcj zto/bY w9+afI +JNUfu XpETQK 2k7dWFBSqC phnTUe y9cRsQ LfPeAX +sUA+n IB5xD7 fnJlF8 SwfMyE K3wuJb PfCKSc yjDkBk 8zXqnr AbDcwdVvMf GofKC4 fnbv6x j81Wyp ip3Zym Dva50x kRAFHB Z2PD+r e6PewB Jwg2NW rrSRf8 vKyRRe 1d4nTKRIYe NhFD2x mcudTw ybhJX/ BenFJD m+Z4JK xk86DT v71laB wywDf7 xhGVBh dLeILX pPDpoH OJV9jsziLY r6FpU1 5U0/0Q xRlv72 XYCbeY cUKvrS pkTgvp NqOhQi KBRxEc +tpS6D 31XcM/ skM9s1 t+gkTTQYpw FT6Q37 r5pdhq P/bENf Nfq4wA p17TnV +Iqz1Q FlmocM YQtp3l N7aopC t//jtL OkbO9r OdUMwq/Yak aySm9L U5IwSJ Lca1gs kUAgyh GNk099 eu9GgC d10kWL EMoX6D lA6bdY 7AYESp nA7hT6 ChZOraHk3+ a7sZDT GElTZI 4sSflA 1ccbmi B9V4HR BieFj4 G0F8qg Gy7ugw BP4DQ0 G8IyJ8 OZprIx 029GlmXibT rWQMgk 3D/EsS 9Jqu4m kcNDdB jij85G HXU/dr uG9eXD 73FtnX MoXBsq cjccXR oDhZxN DnubE+7vhS xR/Gxg L/FmN7 Q/hilg SBiZNw UeMz5M 1CLLag Mp+Lae TNRsbk YryRuv IFck/+ KO2yH8 y9GqQyK90c WoCTQF Yb04UQ OmPHCt ZELs2C HZaE/x 8uaUoO 7tBA0I Um57tZ RZ1gVK pSD4zN hRIPyJ I6efcIC1an JkQnuV 1vdtXr QDzXv3 8gLeK1 yGiBga KOJOBr aIjeBF S39M4L G3sZ2L wGutBe fVyWF2 Z7UOzh2yny IUQ/bS gt0fMM V1+GWE r1f+zh f5QKnL rDMIPi ENg10n SsRQ+E gl5ims 0gEvxc ZuNTgi vN9v6s1EgL wEAMJW IN4dJO fjanbL lro2fS CI4dwG UWqGV2 SOXH6o 8Gs0rM KaiNkb ny4GXQ ZzcBq2 QaJYgrnHM3 I4EhgD VEpPoU djY9hb kGuSDt Pth+9R xqqxxy 6NUlDk sHUiXh 8lq+B0 QLPVNt SaF6Wc BICSPupiCP n8QoEY ZKKK1X qN5qoB qkOtTt 77bbiH xqUC80 eOPdS0 RBsMNL e/AlKL NUmspv KjDzba bnPZtF9BH0 I9yTXr YjMn5K hSRjKD qy+SoL E8xT8Z ZgY1rA ==

The chance was in face 1 in 2^8000, or if you prefer 1 in 1.7E+2048. We could run this universe over many bilions of times and no one would get those numbers again, so treasure them!

So, as you can tell that event above is very unlikely. However, the chance of me getting 1000 numbers out of /dev/random is very close to 1. I'd expect it to fail very much under 1 in a billion times.

In other words, just because a specific event is unlikely (me getting those digits/this type of life evolving) doesn't mean that getting AN event from the class (e.g. some digits from /dev/random or some type of life evolving) is nearly so unlikely.

Re:It's wildly unlikely we should exist

[sinij]

given how complex we are...

Complexity != Quality, or every bloatware and spaghetti coder out there would have created true AI by now.

Re:It's wildly unlikely we should exist

[medv4380]

Douglas Adams logic is simply a fail. Just Substitute Worlds for Numbers, and inhabited worlds with Prime Numbers.

“It is known that there are an infinite number of Numbers... However, not every one of them is Prime. Therefore, there must be a finite number of Prime Numbers... From this it follows that the population of Prime Numbers is also zero, and that any Prime Number you may meet from time to time are merely the products of a deranged imagination."

The Truth is there is an Infinite Number of Prime Numbers in spite of there being space between them. The question really is whether or not the odds of intelligent life is comparable to Prime Number, or to the occurrence of a single solitary number. Also the 1 divided by Infinite is infinitesimal not nothing as Adams asserts assuming you're not a blaspheming finitist. And if you are a blasphemer 1 divided my infinite is nonsensical.

Re:It's wildly unlikely we should exist

[kilodelta]

And then there's the mind boggling distance between us and say another intelligent species in the cosmos. But there's a pattern in human endeavor that says first we think about it, then we build telescopes to view it, then we build probes to orbit it or visit it, and finally we visit.

Re:It's wildly unlikely we should exist

[khasim]

Sure, but it is unlikely we will ever make contact with life outside our own galaxy.

It is also unlikely that we'll ever make contact with another intelligence in our own galaxy. It is 100,000 light years across.

Then comes the issues of whether:
1. They'd have died out before they could reach us.
2. We die out before they've gotten past the "bang the rocks together" stage.

So many things have to happen in just the right order at just the right time. Look at our evolution for an example (the only one we have).

Re:It's wildly unlikely we should exist

[Empiric]

Your random generation loop has run once, insofar as there is scientific evidence.

Since the odds of a sequentially dependent set of events cannot be greater than the step with the -least- probability, it is the fact out of all possible physical laws and initial conditions, we have sentient life rather than "space-time goo" that is the more relevant constraint at hand.

Re:It's wildly unlikely we should exist

[Anonymous Coward]

We are unique given the planet's total life span. Us achieving our level of intelligence and ability as a species is only a tiny sliver of the Earth's total history. I have no doubt that other planets in the universe have or will support life of some sort. Even that intelligent life has or will exist. Odds that such life will exist on the same timeline as us is very unlikely in my opinion. Our existence on Earth is an anomaly and likely would be on other planets as well.

Re:It's wildly unlikely we should exist

[theIsovist]

You're looking for math advice in the logic of a man who willfully (and wonderfully) fucked with the English language to its breaking point. What he likely means is that the density of the universe is basically zero, because, using your modification, the number of prime numbers is infinite, but it grows by a factor slower than the number of numbers. therefore the percentage of prime numbers compared to numbers as x approaches infinity is such a low percentage that it practically becomes zero.

Anywho, it's meant to be comedy, but if you would ever like to bet on us meeting intelligent life within several generations, let me know. I'd like to set up a college fund for my great-great-grandchildren. Space is big and remarkably empty. The only thing larger than it might be their student loans.

Re:It's wildly unlikely we should exist

[TFlan91]

We only think it's outside the norm because our ancestors either assimilated or killed of other species of intelligent life long before anything close to what we consider human civilization ever occurred.

Re:It's wildly unlikely we should exist

[Progman3K]

Obviously that matters, because there are no chimps building skyscrapers or writing posts on Slashdot

Um... I'm not sure whether you're arguing that this is a sign of intelligence or not

Re:It's wildly unlikely we should exist

[DeathToBill]

One flaw? Every single sentence in that quote is either false or unknown. Let's review:

• It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. The universe is not infinite. It may be unbounded (ie have no edges), but that is different.
• However, not every one of them is inhabited. This one might be true. It is, as far as we know. It might be argued we don't know very much, though. Inhabited with what is not specified.

• Therefore, there must be a finite number of inhabited worlds. False, as you point out - supposing that the premises are true, the number of inhabited worlds may or may not be infinite.

• Any finite number divided by infinity is as near to nothing as makes no odds, so the average population of all the planets in the Universe can be said to be zero.The first half is true-ish. Certainly the limit as x->infinity of y/x, for finite y, is zero. What relevance this has to the remainder of the sentence is not clear. If the number of inhabited worlds is finite, then so is their population and each populated world will have a finite, non-zero average population. If the number of inhabited worlds is infinite, then so is the total population.
• From this it follows that the population of the whole Universe is also zero False, since its premises are false. Even if the premises were true, infinity times an infinitesimal number is not zero.
• and that any people you may meet from time to time are merely the products of a deranged imagination. This depends rather on your personal situation.

Re:It's wildly unlikely we should exist

[T.E.D.]

“It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds.

That was a joke, the logic doesn't really work. For instance, there are an infinite number of integers, not every one of them is even, but there are still an infinite number of even integers. Not to mention that there are not in fact an "infinite" number of worlds. There may be a large number of them, but that number isn't inifinite.

Re:It's wildly unlikely we should exist

[zamboni1138]

Thanks for reminding me to go buy a Powerball ticket.

Re:It's wildly unlikely we should exist

[medv4380]

Sorry, but using the logic I presented you'd have to go with what was already defined by Cantor. Both sets are countable thus they are equal. There are exactly the same number of Prime Numbers as there are Natural Numbers. For your assertion to be true you'd have to assume that Space was an Uncountable Infinite like Real Numbers and weather or not Space is like that or now is still debated between Finitists, and Infinitiests. As for expecting logic from Adams, I did not. I was pointing out why you thinking he did a good job in describing the problem was in error. As for people who've actually described the problem aptly I'd cite Fermi, but he leaves it with a paradox meaning most of our pessimistic assumptions must be wrong, but which ones are wrong is always the problem.

Re:It's wildly unlikely we should exist

[Mike Van Pelt]

(quoting Douglas Adams)

“It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds.

There's your problem right there! (Yeah, I'm sure Adams was perfectly aware of this, he was, after all, writing a comedy novel.)

Re:It's wildly unlikely we should exist

[Jason Levine]

Even if we limit ourselves to the Observable Universe, there are billions of galaxies each with billions of stars. If even one hundredth of one percent of those stars had planets, one hundredth of one percent of those planets harbored life, and one hundredth of one percent of those planets with life had intelligent life, we'd be talking about millions of civilizations. We might be so far away from one another that the chances of finding each other approach zero, but there's a very good chance (probability-wise) that other intelligent life is out there.

Re:It's wildly unlikely we should exist

[Empiric]

Sorry, I will have to defer for a while my evaluation of you as a pile of dirt.

Rest assured, though, it will happen.

Re:It's wildly unlikely we should exist

[ShanghaiBill]

It is also unlikely that we'll ever make contact with another intelligence in our own galaxy.

It is unlikely that we will make contact with a specific civilization, but there are 100 billion stars in the galaxy, so there may be millions of civilizations out there.

It is 100,000 light years across.

You don't have to go 100,000 ly in one jump. Even in our neighborhood, the stars are only a few ly apart. In much of the galaxy, they are much closer than that. If a civilization propagates through the galaxy at even 0.01c, that is just a blink on the time scale of geology or biological evolution.

Re:It's wildly unlikely we should exist

[Platinumrat]

There are some pretty unique conditions that allowed life to evolve here. Time and being in the right place (ie. the habital zone) are not the only prerequisites. The Universe is a dangerous place and it's out to kill us or any other life. In planetary science, there is a theory with a lot of support, that says the moon had a significant role to play in allowing life to develop on Earth. For one thing, it creates significant tides, which stirred up the materials needed to form life in the oceans. Another thing, is that without the moon, the earths axis of rotation would not be stable and thus at some times, the poles would likely to be pointing at (or away from) the Sun. That would be bad for life, especially complex life.

Re:It's wildly unlikely we should exist

[rubycodez]

Nonsense, the question indeed is if we are the only one. Other models of the drake equation come up with zero possible other sentient life. We could be the result of repeated extremely unlikely accidents that never happened anywhere else.

Re:It's wildly unlikely we should exist

[drinkypoo]

Let me amend that. There are not a lot of chimps posting on /.

No, mostly they moderate.

Re:It's wildly unlikely we should exist

[MouseR]

Other than the nose and occasional eyebrows, we're pretty much the norm according to Roddenberry.

Re:It's wildly unlikely we should exist

[Roger W Moore]

Let me amend that. There are not a lot of chimps posting on /.

No, mostly they moderate.

It's the trolls that post.

Re:It's wildly unlikely we should exist

[Phoghat]

And the likelihood that most of those have intelligent being who are already extinct

Re:It's wildly unlikely we should exist

[rtb61]

Now that is the only real matter of significance. Of all species on the planet, as far back in the past we can investigate, we will be the only species on this planet to evolve into a galactic species with our presence on more than one world, consider the real significance of that, 1 in 1 trillion. Quite the achievement to either succeed at truly evolving or fail and die in the planetary cocoon (that is the inevitable guaranteed fate by more than one possible major extinction events, we either thrive in the galaxy or die in the cocoon).

Re:It's wildly unlikely we should exist

[Firethorn]

Funny... But Douglas Adams had a logic error in there: "It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in. However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds."

Infinity divided by a constant, such as the percentage of inhabited worlds out of all worlds, is still infinity.

My belief in extra-terrestrial life is this:
1. You look at the Earth and you come up with a fairly staggering amount of coincidences for making life, especially intelligent life, easier to develop.
2. In a given volume of space, you only have a very limited number of stars, relatively speaking.

Roughly speaking, the number of stars within a given distance of a hypothetical planet with intelligent life on it(like us) is on the order of O(n^3). As the targeted feature becomes more rare, the more stars you need for one to statistically pop up, and therefore the average distance between planets with intelligent tool using life increases as the odds of any given star or planet having intelligent tool using life in the system or on the planet decreases.

The rarer we are, the further apart we are on average, in other words. If intelligent tool using life is equivalent to winning a couple lotteries per star, you're looking at hundreds of light years between civilizations. The range at which we'd detect a civilization identical to our own? Less than a light year unless we got lucky.

Re:It's wildly unlikely we should exist

[MightyDrunken]

It is known that there are an infinite number of worlds, simply because there is an infinite amount of space for them to be in.

It is thought by many cosmologists that the Universe is infinite due to theories like inflation, it is not known whether it is or not.

However, not every one of them is inhabited. Therefore, there must be a finite number of inhabited worlds..

Incorrect, even assuming a tiny probability like only one in 10^20 worlds have intelligent like, that results in an infinite number of worlds. The likely reason for us not seeing any evidence is that intelligent life is rare, space between stars is large and there is a maximum speed limit c which takes a stupendous amount of energy to approach.

An intelligent life form would I hope not be silly enough to create von-Neumann probes because evolution would likely mean that in cosmological time they would evolve to create a hegemonizing swarm which would be impractical to eradicate.

Re:It's wildly unlikely we should exist

[serviscope_minor]

Since the odds of a sequentially dependent set of events cannot be greater than the step with the -least- probability, it is the fact out of all possible physical laws and initial conditions, we have sentient life rather than "space-time goo" that is the more relevant constraint at hand.

I'm not sure what you're driving at. The chance of getting sentient life is the sum of the probabilities of every possible path leading there. There is likely more than one possible path.

Re:It's wildly unlikely we should exist

[stridebird]

Well, what if the odds you quote were actually ten thousandth of one percent? 1 in 10**6
stars: 10**9 x 10**9 = 10**18
ILife: 10**6 x 10**6 x 10**6 = 10**18
That's one planet with ILife

and at your odds:
ILife: 10**4 x 10**4 x 10**4 = 10**12
That's 'only' 10**6 planets with ILife

Furthermore that's over a period of something like 10**9 'years' or whenever second generation stars started (no ILife possible on a first generation star). Our Intelligence Life has been around for 10**5 years. Which means the odds of two ILife species existing contemporaneously (or shifted for speed of light) is slim.

Although, in case of Earth, I would expect more intelligent species to arise. The diversity, raw material and time still available for further evolution would make it highly unlikely our species will be the last (ILife) on this planet. I think once life establishes on a planet, it's highly tenacious.

Re:It's wildly unlikely we should exist

[jandersen]

One may argue that we are outside the norm for life on Earth; although i'd argue that there are enough other species that show some degree of sentience; members of genus Corvus, the other great apes, cetaceans, and even elephants, that I'd argue that we are more the most extreme example of a phenomenon found in several lineages, in particular in mammals (though genus Corvus are birds). The differences are more degree. Obviously that matters, because there are no chimps building skyscrapers or writing posts on Slashdot, but it also means that our cognitive abilities are firmly entrenched in evolutionary processes.

I could hardly agree more - but I don't think one CAN argue that humans are outside the norm for life on Earth. As far as I can see, we are now able to produce several, very convincing explanations of how life could have arisen, and how it has evolved from there to what we see now; and my feeling is that there is almost an inevitability about it - what one could call 'statistically inevitable': what you have, when each individual event is not very likely to happen, but there are so many events, that the likelihood of it happening in many places is very high, maybe close to 100%. The one sticking point, according to professor Nick Lane, is the arisal of the first eukaryote: the first cell that acquired an endosymbiont (which became the mitochondria); personally, I think it is because he focuses too narrowly on a path of evolution that is unllikely, namely that a bacterium was suddenly able to enter an archaea (or was it the other way round?) and live in some sort of power balance. It seems that it is more likely that members in a biofilm (which are still very common) gradually evolved the ability to cooperate closely enough to allow endosymbiosis; there may have been more than one kind of eukaryotes around for a short while, but one relatively soon got the upper hand and outcompeted every other kind. On other planets there may perhaps be many lineages of eukaryotes, or perhaps all higher life evolved from incresingly well-organised biofilms; now there's a thought.

Any way - this is all speculation, but the point is - I think there are elements of life and evolution that are statistically inevitable, and that the evolution of intelligence and sentience are amongst them. The reason I think so is that all of these traits are highly advantageous, and the advantage is proportional with "how much" you have of the given trait. Size seems to be one such trait: once it turns out that being bigger is an advantage, it keeps getting better as you get bigger, at least for a while - hence the enormous dinosaurs. Same thing with intelligence and civilisation. An interesting question is, when does the increase in civilisation no longer translate into an improvement in survival of the species?

Re:It's wildly unlikely we should exist

[drinkypoo]

Maybe being intelligent and building technological societies are two different issues and perhaps we developed technology because humans as species are good at form large efficient communication networks just like the termites

The termites have limited needs, and they have the physical ability to secure those needs. Having done so, they have felt relatively little pressure to evolve. We have complex needs, but we also have the physical ability to secure those needs. It stands to reason that we would develop more complexity to secure them (or turn into something else, or go extinct, obviously, but let's stick with possibilities that result in our existence.)

The parrots don't have opposable thumbs and they can't work with fire because they'll burn off their means of travel. Dolphins don't have opposable thumbs and they can't work with fire because they're underwater. Maybe building technological societies just requires thumbs and fire?

Re:It's wildly unlikely we should exist

[edittard]

We know for certain that they don't edit; it's evident that nobody does.

Re:It's wildly unlikely we should exist

[jellomizer]

Because you don't mathematically exists I will just take it as part of a deranged imagination.

Re:It's wildly unlikely we should exist

[david_thornley]

We really don't know how long there will be intelligent life on Earth and perhaps elsewhere in the Solar System (considering "intelligent" to be roughly human or greater). So far, it's only been a very small time in the planet's history, but we may think differently in half a billion years.

Re:It's wildly unlikely we should exist

[david_thornley]

Humans are outnumbered in their own bodies. I don't know how many species of bacteria and similar stuff there were in assorted astronauts, but they went off-planet also.

Re:It's wildly unlikely we should exist

[Man Eating Duck]

I'm not sure what you're driving at. [...] There is likely more than one possible path.

You should be aware that Empiric has a very specific agenda in discussions of this type. Arguing with him (or her) is pointless, as he would have to abandon his entire belief system to accede even one single aspect of your argument. He will, however, go to any length to discredit you and your standpoint.

Just so you know what you're dealing with here :)

Re:It's wildly unlikely we should exist

[peawormsworth]

To quote Douglas Adams...:

“there are an infinite number of worlds... not every one of them is inhabited... there must be a finite number of inhabited worlds... any finite number divided by infinity is as near to nothing”

All worlds × percent inhabited = inhabited world

...so... Infinity × Finite = Finite

Now do you see where Douglas Adams tried to trick you

Re:It's wildly unlikely we should exist

[serviscope_minor]

Oh good point, it's *that* guy!

I often don't check the name of who I'm talking to before replying.

Re:It's wildly unlikely we should exist

[Coren22]

The parrots don't have opposable thumbs

They don't? What do you call the toe that is on the other side of the branch if not a opposable thumb?

https://en.wikipedia.org/wiki/...

Wikipedia says that they have opposable thumbs, in fact parrots seem to have two thumbs on each leg.

Re:It's wildly unlikely we should exist

[drinkypoo]

I don't want to take anything away from parrots, they have pretty dextrous feet. But they're nothing like a hand. They have an opposed digit which is good for grasping, but calling it a thumb is a stretch. It's really the same as their other digits.

Parrots can do stuff like tie and untie knots... but they have to use their beak.

Re: It's wildly unlikely we should exist

[rubycodez]

you don't know, you're talking out of your ass.

meanwhile, zero evidence of life other than on earth. zero aliens or alien tech or alien craft or microbes found on moon or mars.

A number of incredibly unique events have happened in earth's history that may not have happened anywhere else. even the distribution of rocky and gaseous planets in our solar system is abnormal

"Habitable Zone"

[phishybongwaters]

That has always bugged me. Who are WE to determine that life has to be like US. Screw the habitable zone, there is ample life found on OUR planet that is found in areas considered inhabitable. Why assume life out there would be carbon based, breath, and require water? We're looking for life outside of this little snowglobe, but we've placed a mirror infront of the telescope. We'll miss extraterrestrial life because we were looking for ourselves the whole time.

Re:"Habitable Zone"

[Dunbal]

You make a good point. It recalls the argument whether a mayfly actually can perceive a tree as being alive, since the mayfly lives from a few minutes to two days at most, and trees can live hundreds or even thousands of years. But on the other hand - would we have any interest in "life-forms" or beings that have scales or life-spans so large that any perception, let alone communication, between us, is absolutely impossible. It's a bit anthropic but life pretty definitely has to fit within standards we define for us to consider it to be alive. Anything else is simply outside our scope. See? Relativity can apply to xenobiology too.

Re:"Habitable Zone"

[taiwanjohn]

Earth would not be in the habitable zone without plate tectonics. Venus would be in the habitable zone if it had about a zillion times less CO2 in its atmosphere. Mars would probably be in the habitable zone too, if it were bigger and had a magnetoshpere.

It's all relative.

Re:"Habitable Zone"

[thinkwaitfast]

Check out xenopsychology by Robert Freitas (a real phd scientist) and also the concept of Sentience quotient defined s

as the relationship between the information processing rate (bit/s) of each individual processing unit (neuron), the weight/size of a single unit and the total number of processing units (expressed as mass).

At present, human scientists are attempting to communicate outside our species to primates and cetaceans, and in a limited way to a few other vertebrates. This is inordinately difficult, and yet it represents a gap of at most a few SQ points. The farthest we can reach in our "communication" with vegetation is when we plant, water, or fertilize it, but it is evident that messages transmitted across an SQ gap of 10 points or more cannot be very meaningful. What, then, could an SQ +50 Superbeing possibly have to say to us?

Re:"Habitable Zone"

[ShanghaiBill]

Why assume life out there would be carbon based, breath, and require water?

Plenty of life doesn't "breathe", so nobody is assuming that. Early life on earth was almost certainly anaerobic. But carbon and water have some very useful properties, and they are both extremely common in the universe. So assuming that life is carbon based in a liquid water medium is reasonable.

Also, we are searching in extreme environments outside the habitable zone. For instance, we are planning missions to Europa which has far more liquid water than earth.

Re:"Habitable Zone"

[110010001000]

Wow. A real phd scientist!

Re:"Habitable Zone"

[Anonymous Coward]

We don't make the assumptions you state. We do acknowledge that the life we know something about is going to be far easier to identify at astronomical distances. Finding life with different basic principles is a harder problem. We're simply focusing on the easier problem first.

Re:"Habitable Zone"

[Krishnoid]

What, then, could an SQ +50 Superbeing possibly have to say to us?

Who's a good girl? Whoooo's a good girl?

Re:"Habitable Zone"

[Dunbal]

Interesting reading, thanks!

Re:"Habitable Zone"

[serviscope_minor]

Who are WE to determine that life has to be like US.

Well, obviously that's silly, however...

Why assume life out there would be carbon based, breath, and require water?

Because we don't know any better. It's likely that carbon is important. There are several reasons for this. First, it forms stable, complex molecules over a wide range of temperatures. Silicon does to some extent, though the upper limit on the temperature is much lower. Boron also formes long complex molecules readily. There might be options with some metals too.

However abundance is also key. Boron is not formed in stellar nucleosynthesis un significant quantities unlike silicon and carbon, so it is very rare. This is a downside for life, since some non living process would have to concentrate it first.

The next problem is solvents. Likely solvents are hydrocarbons, ammonia, water, sulphuric acid and possibly liquid or supercritical gasses like nitrogen or hydrogen. We know those do exist out there in space. More exotic solvents may well depend on a large quantities of large molecules being formed (unlikely) or concentration of rare elements (also unlikely).

Those solvents will affect what chemistries are possible and what the base molecules are.

Now, the thing with carbon is that it comes in a variety of forms ready made. There's plenty of methane around the solar system, and the interaction with UV makes various other molecules too. However, silicon just doesn't seem to do that which puts it at a disadvantage. Likewise, CO2 is a nice gas which can spread itself around, unlike SiO2 which is rather more rooted to the ground.

So, while there might be non carbon forms of life, the other elements are at a severe disadvantage.

As for solvents, yeah I can see other ones could work. There's a few choices.

Re:"Habitable Zone"

[Immerman]

I think you're grossly over-estimating our ability to look. Trying to spot life across interstellar distances makes looking for a needle in a field of haystacks look like a walk in the park. The sky is just too frigging big when you're looking closely enough to maybe see life. Plus, we don't currently have the equipment to even really try - seeing the relevant details from many light years away is *expensive*, and hard to justify building based entirely on "what if".

So, we're looking for evidence of enough Earth-like places to help justify spending the money to be able to look more closely for the sorts of things that would be relevant to spotting life. And so we look mostly for what is easy to see, not necessarily what's most likely to harbor life, since we really have no idea. For now the only data point we have is that Earth-like planets definitely *can* harbor life.

As for why the specifics? It's true that other liquids might serve in water's stead as a solvent for life-bearing chemistry, but I seem to recall that water has some unusual properties that probably make it particularly well suited to the task. There's probably plenty of planets out there with a viable alternative, but for now we can see so little that a planet's temperature is one of the few things we can make an educated guess about -

As for breathing, for a long time on Earth none of the life did. We're interested in oxygen mostly because it'd be an easy-to-spot "smoke" from life's fire - it's very volatile, so if large quantities of O2 are present in an atmosphere there must be some ongoing process steadily releasing more of it, and life is a prime candidate.

Carbon though - that one is probably special. It's the smallest element capable of making four molecular bonds - most common elements can only make two or three. Making four bonds means it can easily form much more complicated molecules, which is likely to be *extremely* important for building the molecular-scale machines that underpin life. And being the smallest such atom means those bonds are far stronger and have a wider range of motion than they would using the next candidate, silicon, much less anything even larger. That's not to say that other chemistry couldn't exist, but the odds seem stacked against it.

Re:"Habitable Zone"

[DigiShaman]

So, the Universe could be nothing more than a sub-atomic particle for yet another larger universe it sits in. In that larger Universe, our sub-atomic existence is in fact part of what makes up a carbon atom. Zoomed out, that carbon atom is bonded with an organic molecule! Zoomed out further still, it's part of a mass of extruded excrement laying on someone's lawn someplace; forced out by the most ugly dog imaginable; a very very very large dog I might add.

The origins of our existence might not be so glamorous after all.

Re:"Habitable Zone"

[MobileTatsu-NJG]

What I find funny about this discussion is that our whole mathematical proof that extra-terrestrial life exists basically boils down to: "There's lots of places to look." Which is fine until we get to Fermi's Paradox, which reels that back in. There is no math that can determine if we're alone in the universe until we actually meet any. At best all math can say is: "Here's how long it'll take to give up the search."

The best we can do is try to narrow down where we'd search. That's the point of the 'Habitable Zone', it should really be called the "Familiar-to-us Zone'.

Re:"Habitable Zone"

[tnk1]

The chemistry in question is important. We not only believe that in a habitable zone, with the right raw materials, the chemistry for life isn't only possible, it is almost inevitable unless something stops it. Outside the habitable zone, that chemistry may be possible, but is not inevitable.

So, it makes sense to look for life in the places where the chemistry and environment is most likely to bring about a sustainable lifeform in an interval that is less than the age of the known universe. It isn't a matter of "hubris" or "arrogance", it is simply a matter of looking where you have a higher probability that you will find what you are looking for.

Re:"Habitable Zone"

[tnk1]

A superbeing wouldn't find us very interesting or capable of having a good conversation with, but they would not be incapable of communicating with us, if they learned our language and obtained the means.

The real barrier to communication with lower SQ animals is both our lack of knowledge of the "language" they use, and the inability to produce communication in that language. I can see that a dog is happy if he's wagging his tail. What I can't do is wag my tail to show I am happy, and what is more, the dog will know I am not a dog and is therefore likely to ignore an artificial tail wag from me via some sort of fake tail.

A superbeing may not have an inherent capability to communicate with us (for instance, they may not have vocal cords), but they should be able to figure it out. The next question is whether we'd accept the artificially generated noises from an energy being who is trying to vocalize as actual communication. If they get their vocalization wrong in some manner, they could sound like they are speaking too slowly, or in a shriek, or they may seem to babble in a way that is understandable but gets nothing across to us, so we ignore it.

Re:"Habitable Zone"

[lgw]

Why assume life out there would be carbon based, breath, and require water? We're looking for life outside of this little snowglobe, but we've placed a mirror infront of the telescope

Every single scientist looking for life elsewhere understands this. Yup, all of them. So, you have to ask yourself, if you want to look for "it's life, Jim, but not as we know it", what exactly do you look for?

With very limited data indeed, just a barely-resolvable modification to the light of a distant star as that light passes by its planet, we have a chance to detect certainly things about it's atmosphere. With that tiny amount of data, a scientist can look for evidence of life as we know it, by looking for some very distinctive, known, signatures.

Of course the SETI guys are looking for someone trying to contact us, and we may one day discover some cosmic megastructure, but aside from oddball stuff like that, what would you look for?

Re:"Habitable Zone"

[thinkwaitfast]

I think you are looking at it too anthropomorphically. Thinking as communication = subject, verb, adjective object where a higher level being my have no such concepts. They may even be mostly unaware of a physical universe for all we could know and think something like happy happy sad happy sad to convey states which we are incapable of understanding. Their concept of reality might be totally incomprehensible to us and may not even recognize that we are alive like a creature out of Flatland.

Re:"Habitable Zone"

[geantvert]

So according to that definition, a specie that would reach immortality or that would find a way to prevent all mutations would not be alive anymore? I don't think so.

I won't even try to give better definition of 'alive' because I feel that this is pointless. This is a fuzzy concept so there will always be exceptions and some "things" will never be properly classified.

Re:"Habitable Zone"

[pr0fessor]

Not like "Ancient Alien Theorists" oh wait, some of them do have PHDs.

Re:"Habitable Zone"

[tnk1]

The thing is, I can look at an ant and understand what she is doing and have some idea what her wants and needs are. I do have a whole range of thoughts and emotions and such that the ant can't even comprehend, and the ant's communication and thought processes are probably so simple as to defy my understanding on how they live day to day.

However, I know how to send an ant messages, if only to lure them into traps. I think that is a function of knowledge, rather than sentience.

I do agree that there might need to be some knowledge of a flatland and what a flatland entails for me to communicate with such a being. I think most people mistake the ability to comprehend or communicate with our lack of complete knowledge on how to do so. If we could interact with a Flatland, I think we'd have a lot of trouble learning how flatlanders work, but if we made the effort, we'd be able to understand it.

If sentience does anything, it may distract us from making the effort to learn how to fully communicate with a lower SQ being. Or we may consider them unimportant. But it doesn't prevent communication if we decided that, for some reason, it was now extremely important to try. Ants don't usually occupy much of my attention, but they do occasionally intrude in the spring when I need to get them out of my house.

Re:"Habitable Zone"

[rubycodez]

Sorry but all the life on our earth follows exactly one template that can exist only in narrow range of conditions. All life on earth is carbon based and requires liquid water for biological processes, no exception. There is temperature range too ends at just over 120 degrees C for life, above that it dies.

Re:"Habitable Zone"

[AthanasiusKircher]

What I find funny about this discussion is that our whole mathematical proof that extra-terrestrial life exists basically boils down to: "There's lots of places to look." Which is fine until we get to Fermi's Paradox, which reels that back in.

Actually, I'd say the argument really boils down to the Principle of Mediocrity.

We assume that there's nothing too "special" about our place in the universe. And that seems to work well so far when we look at galactic structure or stars or solar systems -- as we gaze out into the universe, we find a lot of stuff that looks superficially like what we see around our "neck of the woods."

The problem is that most of those big structures are dependent on very basic physical principles -- how gravity works, how nuclear fusion works in stars, how much of various elements are present and relatively evenly distributed.

But life is pretty complicated. It could be if you make a "stew" of approximately the right mixture of stuff in the approximately right temperature and gravity conditions, life just self-organizes most of the time. Or, it could be that the "stew" and conditions were much more specific and the requirements are much more narrowly determined (enough so that life is pretty rare in the universe).

We simply can't know until we (1) observe life in other places, which will allow extrapolation and estimation of probabilities, or (2) manage to run our own "creation experiment" to evolve life ourselves in a lab, probably over millions of years -- in which case we can look at the conditions that seem to be required.

So, the ONLY reason for believing it's even worthwhile to look other places is the Principle of Mediocrity. But there's little reason to believe that the Principle of Mediocrity applies equally to patterns caused by really basic fundamental things like gravity and atomic structure vs. patterns caused by self-organizing complex life forms. Maybe it does. That'd be cool -- life everywhere in the universe. Maybe it doesn't, and we're pretty rare.

There's no "mathematical" argument to be made here at all, until we have more than one data point.

Re:"Habitable Zone"

[Daetrin]

Minutephysics posted an interesting video putting forth a theory i don't think i've ever heard before along those lines: https://www.youtube.com/watch?...

The short version is, given a set of randomly chosen groups there will be a distribution of various factors, in particular for this case we're concerned about size, in which _usually_ it follows some kind of bell curve.

Take countries, if you measure population a very small number of countries have high populations and contain the majority of the human race. If you measure size, a very small number take up a large area and contain the majority of the available surface area of the planet. If you pick a random person or a random square mile it is very likely it will be from one of those populous or large countries. But there are (comparatively) a huge number of other, smaller, less densely populated countries on the planet.

So by the same rule, statistically speaking, we should expect that we are one of the most populous species occupying one of the largest inhabited planets. And we should expect to find _many_ other species, each of which inhabits a small world and has a comparatively small population. And if you continue along those lines you should also expect those planets to be in closer orbits around smaller, dimmer stars, etc.

Of course there are some obvious problems with this theory. It is only a statistical likelihood for starters. _Someone_ has to be living in the smaller places, and maybe, against the odds, we are the "minority" and there multiple other races with trillions of members living on giant planets. Or of course we might be the only one.

Another "problem" with this logic is that i've seen the same argument used to "prove" that the world is about to end. The total human population keeps going up over time. You are statistically most likely to be born during the time of the greatest population. Therefore the population will _not_ continue to go up in the future, in fact statistically speaking it "ought" to be smaller than it is now, and the smaller it is in the future the more likely you are to be born during the time in which you actually were born. Ergo the world is about to end.

Re:"Habitable Zone"

[gtall]

We've already found alien life: cats. For them to be anything other than alien is absurd.

Re:"Habitable Zone"

[epine]

So assuming that life is carbon based in a liquid water medium is reasonable.

More than reasonable by the standards of conversation in the hot tub at my local swimming pool.

On dry land, however, I prefer to aim a lot higher.

Re:"Habitable Zone"

[Graymalkin]

Who are WE to determine that life has to be like US.

Your question comes up in one form or another every time this subject is discussed. It's not because it is insightful (despite the moderation) but because the questioner fails to think logically.

Firstly the question makes a logical leap by presupposing that it is life on Earth is a rare form in the universe. It suggests that forms of life completely alien in understanding exist throughout the universe and it is the Earth that is the odd ball by using carbon and water as the backbone of biological processes.

For the cosmic awesomeness that is our home planet and solar system, it's pretty average in a large number of ways. The Sun isn't super unique in many respects nor are the elements on which it and the Earth are composed. There's not a whole lot of Unobtanium or Raretonium to be found on Earth. We might be the only life in this part of the galaxy but that's likely not because the Earth and our solar system is especially unique on the galactic scale.

We'll miss extraterrestrial life because we were looking for ourselves the whole time.

The second major problem with the question is the scope is amazingly out of whack with the scope of the actual universe. Our galaxy alone has hundreds of billions of stars. If we could take a galactic census (say in just a 1kpc sphere) we would probably find millions of worlds with some form of life on them. Out of those millions your question presupposes that life forms unlike us would be the majority. Even if that was the case that still leaves a great many life forms that are enough like us for us to recognize as life forms.

Where your question fails in scope is not realizing that just a small chunk of the Milky Way has millions of stars and very likely millions of planets. Even if a majority host life forms wholly alien to us, there'll be enough Earth-like worlds for us to find life that is not wholly alien to us.

Re:"Habitable Zone"

[Gavagai80]

There are, however, numerous places in our own solar system which could satisfy all the life conditions we know of -- inside several moons, under the surface of Mars, maybe even inside Pluto. Not just in our habitable zone. Of course, life in an internal ocean is unlikely to be able to develop space technology even if it is intelligent.

Re:"Habitable Zone"

[Evtim]

If we postulate that life and sentient life forms require certain level of complexity of structure and interactions of the "carrier", then you have limited set of possibilities of materials and interactions that can give rise to those complex structures. Carbon [plus a handful of light elements - e.g. H, N, O] under certain conditions is the champion of champions when it comes to complex structures [we are familiar with all naturally occurring elements and their relative abundances in this universe and what structures they can give rise to under all possible conditions]. You can also play a bit with the other 2 members of 4a - Si and Ge, but carbon is king. There is a lot more to that of course, like suitable solvents [water] and so on...

Also, if we assume there are enough life forms out there for good statistics then there is some sort of normal curve. So, us, being one point of it we are more likely to be "normal" and thus represent the "normality".

So looking for ourselves is not devoid of reason.

Re:"Habitable Zone"

[sociocapitalist]

Check out xenopsychology by Robert Freitas (a real phd scientist) and also the concept of Sentience quotient defined s

as the relationship between the information processing rate (bit/s) of each individual processing unit (neuron), the weight/size of a single unit and the total number of processing units (expressed as mass).

        At present, human scientists are attempting to communicate outside our species to primates and cetaceans, and in a limited way to a few other vertebrates. This is inordinately difficult, and yet it represents a gap of at most a few SQ points. The farthest we can reach in our "communication" with vegetation is when we plant, water, or fertilize it, but it is evident that messages transmitted across an SQ gap of 10 points or more cannot be very meaningful. What, then, could an SQ +50 Superbeing possibly have to say to us?

Why are you destroying your planet?

Re:"Habitable Zone"

[AthanasiusKircher]

This has actually been done. It only took about 40 years or so.

No it hasn't. You're probably thinking of the Miller-Urey experiment or something similar. These experiments have shown that some conditions assumed to be like early Earth can produce some amino acids and other important organic compounds which are found in most living things.

That's all very interesting. But it's a FAR cry from evolving an actual living thing (like a single-cell organism) in a lab. There are lots of theories about how self-replicating molecules come into being (and how they gradually combine in larger structures, some of which has been done in lab experiments) and then how various stages in abiogenesis might work, but we are quite far from being able to demonstrate all the stages in a lab... let alone do an entire evolutionary process from basic chemicals to a living cell or something.

Re:"Habitable Zone"

[Man Eating Duck]

A superbeing may not have an inherent capability to communicate with us (for instance, they may not have vocal cords), but they should be able to figure it out. The next question is whether we'd accept the artificially generated noises from an energy being who is trying to vocalize as actual communication.

This is a very interesting subject, albeit on the verge of philosophy; but a significant difference between us and animals is that humans are capable of abstracting communication beyond the physical transport, whereas animals are restricted to their evolved means of communication.

The cliché is a sequence of prime numbers, which would be a red flag for determining that a sentient being must be the originator. From there it would be possible to establish a dialogue of "challenges and responses" which could be used to establish semantics and syntax for communication. In addition a superbeing capable of observing the Earth and all its comminucations would probably be able to infer understanding of our languages from simply correlating the massive corpus of our public communications with other observable happenings in our community. Whether or not they would have anything to say to us that would be meaningful for us is another question entirely :)

Our lack of ability to converse with ants involves at least our inability to understand/replicate ant pheromones and the presumed inability of the ants to form abstract thoughts and thus understand whatever we had to say. The first would be mitigated if the ants were capable of bootstrapping communications from simple math fundamentals, the second issue makes successful communication essentially meaningless. On the other hand, maybe a simple pheromonal instruction that says "go there" would be hugely beneficial to ants, but so would dropping a pile of sugar beside their mound be.

I would think that our ability to abstract, and to comprehend much of the processes that occur around us, would enable a superbeing to impart more useful information to us than we are able to communicate to ants. But this is still pure speculation; all bets are off when it comes to what the concerns and interests of a being vastly more advanced than us might be.

Re:"Habitable Zone"

[stigmerger]

What I find funny about this discussion is that our whole mathematical proof that extra-terrestrial life exists basically boils down to: "There's lots of places to look." Which is fine until we get to Fermi's Paradox, which reels that back in.

Fermi puts bounds on variables in Drake's equation. If L were infinite, then any such civilizations that had evolved long enough ago that their signals could have reached us by now would be in principle detectable. The fact that we haven't detected them would imply an upper limit on how many there might be. On the other hand, if all such civilizations die rapidly from a Malthusian collapse (as ours appears to be doing), then there could have been many many more such civilizations, without our necessarily being able to detect them.

Or, put another way, if you think detectable life could evolve easily, then Fermi implies L is small.

Re:"Habitable Zone"

[rubycodez]

Some rather unique things happened to earth in its past though; we may well find those are necessary for life to form and so the rest of system might be sterile. Of course, I fully support our exploration to prove that point wrong, and I wish to be wrong

Re:"Habitable Zone"

[RespekMyAthorati]

and think something like happy happy sad happy sad to convey states which we are incapable of understanding.

Or Darmok and Jalad on Tanagra?

Re:Can't Stump The Trump

[NEDHead]

Build a wall?

Mathturbation

[frenchgates]

This is just silly. The Drake equation has always been a joke. It's an extrapolated tautology that the chances for life on other planets are based on the chances for life on other planets.

Re:Mathturbation

[myowntrueself]

This is just silly. The Drake equation has always been a joke. It's an extrapolated tautology that the chances for life on other planets are based on the chances for life on other planets.

The worst part about the coverage of this is that the math is claimed to be EVIDENCE that technological civilizations exist on other planets.

Re:Mathturbation

[naasking]

The Drake equation is perfectly sensible. The key is choosing a reasonable parameters, and the only humour to be found is how ridiculous some people's choices are.

Re:Mathturbation

[Z00L00K]

I played with it once and for the Milky Way I got a value of 0.8.

I think that life may prevail in many unexpected places, but intelligent life and even more intelligent life with technology is a lot rarer. Even on earth we have other intelligent species - like dolphins and even raccoons. But they don't use technology.

Re:Mathturbation

[T.E.D.]

It was never meant to be a descriptive mathematical formula, like Bernouli's Equation. Its just a way to break questions about the amount of life in the universe down into manageable chunks that can be reasoned about. Complaining that its not a real equation is like a software engineer going up to a network engineer and telling them a "protocol stack" is a joke because its not a real design pattern. Perhaps you are technically right, but seriously, find more productive things to attack.

Re:Mathturbation

[AthanasiusKircher]

The Drake equation is perfectly sensible. The key is choosing a reasonable parameters, and the only humour to be found is how ridiculous some people's choices are.

No, the key isn't choosing "reasonable parameters." The key is choosing parameters that actually describe how to calculate probability for intelligent life.

And the problem is that we have absolutely no clue what those parameters might be, since we are only one kind of intelligent life, and perhaps intelligent life can evolve in vastly different conditions that we just wouldn't even consider the mechanism for because it's so different from our own. It took the human race millennia of civilization before we came close to realizing that there might even be a mechanism to drive our own evolution, and we have the hubris to think that we could come up with all parameters necessary to evaluate the possible evolution of ALL POSSIBLE life in the universe after merely a century of so of even contemplating our own evolution??

So, we can narrow down the Drake equation and say, well, it's really about life evolving in situations something like our own. Okay, fine.

Except then, again, we have no idea what the relevant parameters might be, not to mention their relative likelihood. It all comes down to a futile attempt to extrapolate probability from one data point.

Maybe there's some step in the process that's really hard to overcome in abiogenesis. Maybe it requires a very specific mix of materials, much more specific than we imagine. Or maybe there's something else about the conditions that need to be really specific. Or maybe if you just get something roughly the right mix and let it stew for a billion years, life will always evolve.

We simply don't know. We don't know the relevant parameters, because we only have one place where we have observed life evolve, and even then, we didn't observe it -- we are trying to extrapolate evidence of what happened billions of years ago from a time where there are no fossil records.

Personally, I think it'd be really cool if life just popped up on any planet with roughly the right conditions. But it could also be that there's some step in those parameters which makes it rare enough that we're the only life in the galaxy or even in the observable universe. I may think that sounds unlikely -- but there's absolutely no evidence to base such an assumption on.

It's like you're presented with a number: 235759345. And you're told that there's something generating numbers. How rare is "that kind" of number. You have no idea. Maybe the constraint is "all numbers divisible by 5," in which case that number's pretty common. But maybe the constraint is "all numbers that end in 5759345," in which suddenly the constraint is pretty specific. Regardless -- with only ONE number (one exemplar) you just have no idea how hard or easy it is to find that number among the generated ones.

You can't extrapolate from a single data point.

Re:Mathturbation

[Dread_ed]

It's a form of apologetics for believers of the great sky aliens.

They have cleared a place in their heart for the non-existent aliens to live. They preach that when we discover the magical sky creature aliens it will unite humanity, and usher in a new era of cooperation and prosperity. War will pass away and we will ascend to take our place with the beings of light that traverse the universe at a whim, wield mighty forces without repercussions, and posses no malice. They proselytize with equations and probability, talk of certainties and timelines for contact.

Bullshit.

There are no aliens. None have been observed, ever. There is no life on other planets. It doesn't exist. Quit tickling the "God believing" part of your brain with alien fantasies. Its counterproductive and idiotic. It makes you look like a True Believer and that reeks of religion.

Instead, try reality on for size. In all of the universe, with all of its innumerable galaxies, stars, and planets, this is the only one with life on it. Just this one simple blue orb in all of the infinitely vast sterility of space. Populated and peopled with incredibly complex and delicate expressions of the fundamental properties of elements and forces that make up matter. A mathematical impossibility, in spite of the vastness of space. The only example of its kind and the only one that ever will be.

And you dumbfucks are shitting all over it. Thanks.

Re:Mathturbation

[mvdwege]

The Drake equation is merely the Shahada of the religion of SETI.

Re:Mathturbation

[abies]

As far as I remember, it doesn't take time into account. Assuming that high-tech civilization survives only for few thousand years (and it is probably overgenerous estimation), amount of civilizations existing at same time is still very small. I don't think that existence of half-million year old ruins 3000 ly away is going to be any factor for as ever.

Re:Where is everybody?

[Dunbal]

Who is? What - Captain Hollister?

And two months ago, a completely different outcome

[tekrat]

What happened to the scientist that modeled the universe and concluded that not only are we alone in the universe, according to his model, even we shouldn't exist?

I remember commenting on that story, claiming it it was a near-mathematical impossibility for us to be alone in the universe, and his model was wrong. Of course, the usual naysayers came out of the woodwork, but now lo' and behold, here's another story that supports my assertion.

Of course, next week, we'll be back to being alone in the universe.....

It's a dark forest

[Anonymous Coward]

People should really read The Three Body Problem series. Not only are we not alone, but we definitely don't want to be found.

Re:It's a dark forest

[david_thornley]

Good read, but very implausible. The aliens evolved intelligence and developed technology in a wildly unstable environment, which presumably took hundreds of millions or billions of years (generalizing from a sample of N=1, of course). At that point, they'd have adapted to pretty much anything that could be expected to happen on their planet in the next ten to a hundred million years, and wouldn't need to embark on a crash conquest. Since they can make superpowerful computers out of single protons, they'd have no problems predicting the orbital mechanics of the system for a long time to come, and I'd suspect a civilization capable of sending significant mass to Earth at 0.01c would be able to modify their planet's orbit.

Re:Well

[frenchgates]

Sad. Once the internet was opened to the general public it began its rapid decline into heat death.

Missing parameters

[smoothnorman]

Just suppose there has to be temperature oscillations on the order of a year in order to nudge amino acid chains into lipid vesicles, so seasons are required for life. In order to have seasons you have to have your planetary axis significantly different from your orbital axis, so you have to be hit at just the right time post accretion by a body of just the right size at just the right distance from your host star. This is just one silly example of one of a vast number of life "requirements" we're currently ignorant of yet to be factored into "the math". Once the most significant factors are established then probabilities can be estimated; but there's no reason to assume we aren't just cranking out random results at this point. Step one: what are the essential conditions for abiotic goop to become self replicating.

Size of the Universe answers this question

[gurps_npc]

When you look up in a sky full of stars - all of which belong to the Milky Way Galaxy.... (at least 9,000), and about 4 other galaxies.

And know that with a common telescope we can detect both far more stars within our galaxy (over 100 billion) , AND a whole bunch of other galaxies...

And know that the galaxies form clusters - and cluster contains about 100+ galaxies (often 1000+)....

And know that there are thousands of clusters...

Basically, there are more stars than grains of sand on earth, than water molecules in a drop of water, than seconds in all of humanity's life span.

Yes there's other life out there. Now, whether it's intelligent, still alive, within a reasonable travel/speaking distance of us, that's another story.

Re:Size of the Universe answers this question

[myowntrueself]

When you look up in a sky full of stars - all of which belong to the Milky Way Galaxy.... (at least 9,000), and about 4 other galaxies.

And know that with a common telescope we can detect both far more stars within our galaxy (over 100 billion) , AND a whole bunch of other galaxies...

And know that the galaxies form clusters - and cluster contains about 100+ galaxies (often 1000+)....

And know that there are thousands of clusters...

Basically, there are more stars than grains of sand on earth, than water molecules in a drop of water, than seconds in all of humanity's life span.

Yes there's other life out there. Now, whether it's intelligent, still alive, within a reasonable travel/speaking distance of us, that's another story.

This is all great and stuff. But it isn't evidence of the existence of other life.

Re:Size of the Universe answers this question

[myowntrueself]

It is if life is a intrinsic result (rather than a possibility) of some common parameters, then it would mean that there would have to be life.

There would need to be evidence of this...

Re:And two months ago, a completely different outc

[whimdot]

There are naysayers living in the woodwork? My God. Are they intelligent?

Re:You Cannot Get Something From Nothing.

[fredrated]

Matter just does not materialize on its own. So someone either brought us here or they made us here. Either way we came from some place else. So the answer is YES.

OK I'll bite. Who created the someone that brought us here?

One cannot judge with a sample of one

[aepervius]

Drake equation and this all table everything on values for which we have no estimate. It is entirely possible that those values are overvalued (sic) and actually we are the only intelligent life, and that intelligent life is rare and gets wiped out quickly (on the universe time scale) such that there is only 1 at a time in the whole universe. We don't know. And we have no way at this point to know barring a signal of ET origin being caught by our various radio observatory. And they could be trying to listen hopelessly. This article like any other based on drake equation is fluff.

Only for all practical purposes

[NotDrWho]

Having company is meaningless if it's

Too far away to ever call
Too far away to ever visit
Living in a different time period

I'll wager a gamble

[Xenna]

So we have this big bang which creates a huge amount of energy.
This energy converts to matter in the form of hydrogen.
The hydrogen sticks in big clumps which react to form different atoms.
The different atoms stick together to form planets.
The atoms stick together and organize themselves to form life.
Life organizes to form intelligence.
Intelligence sticks more atoms together to organize more intelligence.

It seems to me this is just the way things go with big bangs. Intelligence is probably just about inevitable.

Alone? No

[SenseiTim]

Carl Sagan, Isaac Asimov, Arthur C. Clarke and many other scientist/SF authors have been saying this for almost a century!

This is Crap

[logicnazi]

We have nothing but pure guesswork to go on in estimating the probability that intelligent life will evolve from microscopic life over a given time frame and not much more to go on in estimating the probability of life arising in the first place.

Yes, I personally find the arguments that we aren't the only intelligent life in the universe compelling but suggesting that MATH tells us this is true is simply misleading. People whose prior probability that intelligent life evolves given a suitable planet is super low are perfectly justified in their beliefs.

Re:This is Crap

[burtosis]

We have nothing but pure guesswork to go on in estimating the probability that intelligent life will evolve from microscopic life over a given time frame and not much more to go on in estimating the probability of life arising in the first place.

Yes, I personally find the arguments that we aren't the only intelligent life in the universe compelling but suggesting that MATH tells us this is true is simply misleading. People whose prior probability that intelligent life evolves given a suitable planet is super low are perfectly justified in their beliefs.

This is the exact same argument I heard from people 25 years ago about the existence of planets outside our solar system. I had people who were scientists (not in cosmology/astronomy) try and say planets were probably rare and we may have the only ones around right here. While it's true we did not have evidence at the time, the whole argument just seems that much sillier today as using common sense and extrapolation don't always lead you astray.

Re:And two months ago, a completely different outc

[MightyMartian]

People, even scientists, say lots of rather silly things. Sometimes scientists say silly things to get some attention. Sometimes some idiot science "journalist" greatly overblows a point that a scientist was trying to make. You notice how every time some new hominid fossil is found, the press reports "This could revolutionize evolution!" when, almost always, as interesting as the find may be, it's hardly revolutionary in that it doesn't overthrow any major theoretical work, but usually just refines it.

And in the real world

[gweihir]

They have absolutely nothing. Likely, unlikely, they cannot say without making invalid assumptions.

What are the odds?

[lw54]

How do the one in 10 billion trillion odds compare to the odds of us living inside a simulation?

Re:How the hell can we claim this?

[MightyMartian]

It happened at least once, which makes it happening other times more likely. When you factor in the sheer number of potentially habitable worlds in the Universe, it's hard to argue that somewhere in those vast stretches of time and space, other worlds haven't produced life, and that a few of those worlds have produced sentient life.

Re:You Cannot Get Something From Nothing.

[Locke2005]

Given the law of cause and effect, any creation story requires an event without a cause at some point. The alternative is a huge loop that creates itself. Evolution is not that bad a concept, given 3 billion years, a lot can happen. Also, one sexual reproduction evolves, there IS some intelligence -- animals get to choose their mates, and they would quickly evolve the ability to choose mates that give their offspring the best chance of survival (that's why we all want to sleep with supermodels, it gives our children the best chances for... oh wait.) Back to "someone made us"... who made that someone? EVERY theory suffers from the violation of causality issue, including creationism!

Gripe: Math versus Science

[jfengel]

Science is respected for its reputation for certainty, and Math is seen as the purest (and thus most certain) of the sciences.

This bugs me. Math, on its own, is so "pure" that it has no connection to the universe whatsoever. Aliens don't appear in pure math. Neither do electrons, polymers, or three-toed sloths. Math is purged of all real world things. Math can't predict anything about the real world. Even the simplest tautologies, like "two apples are equal to two apples", requires extra real-world semantics to apply an abstraction like "equal" (which has many different definitions) to actual things like "apples".

So when people say "according to math", they're aspiring to a certainty that it doesn't earn. You could say "according to science". Science will always incorporate some form of math. But it's not identical, and if scientific claims seem "weaker" than math claims, we just need to live with that. Because we don't, in fact, really truly mathematically "know" anything about aliens. Not even a probability: our probability estimates are themselves subject to enormous amounts of guesswork.

Sorry for the distraction, but this bugs me. The article itself doesn't seem to be of much merit; it's all old news. So I'm gonna gripe about the headline instead. Thank you for your time.

Re:Gripe: Math versus Science

[burhop]

And your proof for this is?

Proofs are boring. That's a given.

Re:Gripe: Math versus Science

[minstrelmike]

According to math, the Drake equations are bullshit.
If you add enough time to any probability, it becomes certain. Therefore you cannot use time anymore than you can multiply or divide by zero and get anything useful.

To calculate the probability of life in the universe accurately (as accurately as guesses can be ;-) without incorporating time, then all you need is the number of stars currently in the universe. I'm going with 10 to the 20th power. That means in order for life to be unique on our planet, we just have to have 20 events each with a 1 in 10 chance of occurring. Doesn't seem as likely now, does it?

Remember, multiply anything by zero means you end up with zero.
Adding in enough time (or throws) makes _any_ probability certain which is why real statisticians avoid time.

Re:Gripe: Math versus Science

[david_thornley]

There's nothing mathematically wrong with the equation. The problems are that, in the later coefficients, we're making wild-ass guesses from a sample size of 1, so the science is wildly speculative. Also, real statisticians have no problems with time or infinity.

Re: And yet ...

[Anonymous Coward]

Maybe this is why we don't see any intelligent life. Civilization always ends up generating a Trump, who becomes the leader and then who then manages to destroy the planet.

Re:Michael Crichton on the Drake Equation

[Archangel Michael]

You are a Climate Change Denier! You must be cleansed! Climate Change is Settled Science! The Consensus says so!

Re:We're alone else we'd have been colonised by no

[Kierthos]

Depends on how old those civilizations are, now doesn't it?

The earth is ~4.5 billion years old. Human civilization as we know it is only ~6,000 years old. (Modern humans as a species are only ~200,000 years old.)

There could be other civilizations out there that are centuries behind us in technology, or on par, or far ahead of us. Hell, there could have already been races that hit their version of the singularity and are so far beyond us that they are undetectable.

Re:And two months ago, a completely different outc

[pr0t0]

I think the quote from Contact's Ted Arroway sums it up the best:

I'd say if it is just us... seems like an awful waste of space.

Advanced?

[Tough Love]

Advanced? Can't cure the common cold, let alone cancer. Still burning fossil fuel for power. Can't get ourselves to the next planet, let alone next star. Still running Microsoft Windows. Primitive savages, I say.

Re:And how does that help us?

[Archangel Michael]

Define "poor". Poor from today, look very much like upper middle class from 1960. We have TVs and Microwave Ovens, cars that last a long time, and housing that is more efficient.

Saying "help the poor" is always a noble cause, but the definition changes over time to the point where the term itself is meaningless. The Poor in America are living much much better than most of the middle class in places like India. American poor are in the 10% that Bernie Rails against. It all depends on what the demographics you're looking at. It is how Bill and Hillary consider themselves "poor" upon leaving the White House earning millions of dollars in speeches.

So, when you say "poor", I say that is just relative, nonspecific term.

Lem

[Ferocitus]

Lem proposed many years ago that we might not recognize intelligent life even if we were looking at it.
How would we know if the red spot on Jupiter was a life form? And what could we do if we knew it was?

Re:Lem

[MightyMartian]

Well, if we knew the red spot was a life form, we could at least study it to figure out what kind of metabolism it had, how it reproduced, etc. It might be very hard considering it's floating in the second largest gravity well in the solar system, but you could at least learn some things.

At the moment the best we can do is probably recognize life that is reasonably similar to life on Earth; i.e. is carbon-based, uses ATP or a similar molecule to produce energy, uses some sort of nucleotides to store genetic information, has a cell wall or membrane, and so forth. Yes, one can envision life that works in very different ways, and there has been research into the possibility of life based on other elements; for instance silicon, or the use of other solvents, like ammonia, as opposed to water. There may also be numerous ways to create a genetic code far different than RNA and DNA, so the field could be very wide indeed.

One thing is clear, and that is life wherever it is and however it is formed will have to solve a similar set of problems, and if it becomes widespread, will have a significant effect on the worlds it inhabits. Life on Earth pretty much remade the entire atmosphere, which tells you how significant the geological consequences of life can be.

Re:Well

[sinij]

Sad. Once the internet was opened to the general public it began its rapid decline into heat death.

Netcraft has confirmed: The Internet is dying!

Re:You Cannot Get Something From Nothing.

[MightyMartian]

In other words, you invoke an entity which you give the attribute of "uncaused" to. I will invoke Occam's Razor, remove the unnecessary entity and give the attribute of "uncaused" to the Universe.

Re:You Cannot Get Something From Nothing.

[MightyMartian]

Wanting to copulate with supermodels demonstrates how cognition and emotion can override biology. If we really wanted to guarantee successful reproduction, going for women who starve themselves is pretty idiotic. Better to go for a nice plump (but not too plump) pear-shaped woman in her late teens to late twenties, in the prime of life and good wide hips to minimize the chances of a medical crisis in labor that can kill both baby and mother. If it wasn't for the fashion industry, we'd still be idolizing Marilyn Monroe, and not those anorexics that appear on fashion mags.

Re:You Cannot Get Something From Nothing.

[RatBastard]

And none of those things have to do with evolution. You might want to spend some time figuring out what the hell you're arguing against in the first place.

Mental masturbation

[Dog-Cow]

The question of whether there is recognizable life outside our solar system is not a matter of statistics. Either there is life, or there isn't. The formula is entirely meaningless; either we (as a species) will encounter such life, or we won't. The likelihood is irrelevant.

Re:And how does that help us?

[Z00L00K]

Define "poor". Poor from today, look very much like upper middle class from 1960. We have TVs and Microwave Ovens, cars that last a long time, and housing that is more efficient.

I have seen houses in the US and compared to houses in Sweden they aren't very efficient.

Re:You Cannot Get Something From Nothing.

[Z00L00K]

Go study quantum mechanics and come back.

Re:We're alone else we'd have been colonised by no

[UnknownSoldier]

> The earth is ~4.5 billion years old. Human civilization as I know it is only ~6,000 years old.

FTFY

Stop assuming what other people know.

i.e. You're ignorant of the civilizations of Mu, Lemuria, and Atlantis for one.

--
First Contact will be allowed ~2024. Are you ready for a larger perspective?

WTF!

[no-body]

Depending on your religious or whatever other believe-system-ROM, if you can switch that off for a couple of ms and estimate the number of known Super-Clusters, maybe 10 millions, multiply by the number of galaxies there, maybe 100 or so, then multiply by the number of suns/galaxy, couple of billions then you get probably a register overflow or crash.

Anyway, the number is /void/, and chances that the conditions for organisms with DNA or some other mechanism can develop 100 %.

So, who cares except the strictly on believe-system-ROM running machines around here... get an upgrade, will you!

Re:Can't Stump The Trump

[NEDHead]

It doesn't matter how big it is! They'll pay for it!

Re:You Cannot Get Something From Nothing.

[Empiric]

Occam was... a) theist b) clearly rejecting this now-ubiquitous notion that his Razor could ever be used to arbitrate what is actually the case--rather, given multiple possible models with precisely equivalent evidence, it advocates the simplest one should be used purely for conceptual economy; it says nothing about what is true or "probably true"

Re:Simulation argument

[random coward]

Could be both.

Lying headline

[Spazmania]

The headline is a lie. You can't project probabilities from a single known example. The math doesn't work that way.

Your math, maybe

[PPH]

If you assume things, like the value of Pi being some crazy irrational number, then perhaps you arrive at this conclusion. But if you stick to Pi = 3, like the Bible says, you will have the truth revealed!

Reverse Calculate Average Lifetime of Civilization

[LionKimbro]

I'd be interested in seeing a paper that estimates the maximum lifetime of a technological civilization, on the basis that : (A) the estimates given are right about the number of stars, how many habitable planets are in the goldilocks zone, etc.,., (B) we are not atypical, and then (C) that we have not encountered signals from any radio emitting civilizations.

We might find that there would be so many technological civilizations, that technological civilizations should only exist for a few dozen years. Or we may find that they are so rare, that it's extremely uncommon that they overlap, and they may well last for several millennium.

Re:You Cannot Get Something From Nothing.

[MightyMartian]

Fine, call it parsimony then. There is no evidence for a Prime Mover, and if "uncaused" is a requirement (and it may not be, it may simply be a side effect of how we view the world around us, there's no reason to think causality applies to the origins of the universe), then the most parsimonious explanation is that the Universe is uncaused.

Re:And yet ...

[HiThere]

The Fermi Paradox would seem to contradict that. ( https://en.wikipedia.org/wiki/... )

OTOH, recent advances seem to indicate that while there are lots of systems with planets, our configuration is quite unusual. So perhaps, though not alone in the universe, we are alone in this section of the galaxy...and how big a section is questionable. Some estimates seem to indicate that the probability would be this 1/8th of the galaxy (figure wholly invented...but tells you my estimate). And that's for multicellular carbon-oxygen based life.

OTOH, I don't believe we have good estimates for red dwarf systems. And that's the most numerous kind of star.

That said, there's lots of places in the Drake equation where they are using "best guesses" for values. So don't take this estimate seriously. But the Fermi paradox *is* worrying.

Re:You Cannot Get Something From Nothing.

[Empiric]

In your extremely constrained context of discussion, perhaps.

The primary reason to consider that causality applies here as well is that the overwhelming majority of phenomena we observe does, and if I ask if you'd naturally then question any other phenomenon we observe as having any cause at all, I don't really need to hear your answer, nor your psychological motivation for special pleading this in particular.

And yes, there is evidence, a great deal of it. How is it you know the sum totality of evidence experienced by other people than yourself, anyway? Psychic powers?

"According to Math" ARRRRGGH!

[Cajun Hell]

The conclusion is very easy to believe, but it's embarrassing to all of us when people think they can use math to skip over science. And that's just what you sound like, when you say something as stupid as "according to math." Holy fuck that's grating.

Your equation only predicts the probability of a hypothetical situation (which may, or may not, be similar to reality) based on a some totally made-up numbers that you plugged into it. Even if you're right (and I think you probably are) you're no better than String Theorists or Creationists.

Re:You Cannot Get Something From Nothing.

[MightyMartian]

Waving your hands in the air and pointing everything declare "that's evidence", isn't evidence at all.

And virtually nothing is known about the starting conditions of the Universe, so there is absolute no reason to assert that causality was a factor at the moment the universe began (which may, in fact, not even have been the Big Bang at all). And even if I accept causality is necessary, it still means at some point, something was not bounded by causality, but where you and I differ is you invoke an extra entity which the best evidence you can provide is to assert, with little or no justification, that everything is evidence of, whereas I would accept that the Universe was uncaused in and of itself. The benefit being, I know the universe exists. I have absolutely no evidence of a Prime Mover.

Define Alone

[TomGreenhaw]

Given the vast distances and time that separates anything we would identify as "us" we already know that we are for all practical purposes alone.

Re:Define Alone

[bloodhawk]

Given the vast distances and time that separates anything we would identify as "us" we already know that we are for all practical purposes alone.

That is only true for our current level of technology and understanding of space and time and assumes also that others are at or below our current levels.

Re:Define Alone

[TomGreenhaw]

Agreed. But by "we", I mean my fellow humans alive today.

My thinking is that by the time humans devise FTL travel, you and I will be long gone. I personally don't think FTL travel will ever be possible and if it does, it will be a really long time from now.

As for the others, in the unlikely event that aliens come here they would likely not be like us at all. For example, if its just me in a cage with a cobra snake I say I am alone.

Re:Define Alone

[T.E.D.]

But we don't know that. There are about 50 star systems within 15 light years of us. On the planetary level we have almost no idea what's in all of them.

Re:Define Alone

[TomGreenhaw]

We do know that we cannot detect artificial radio signals from anything within that range.

Re:Define Alone

[T.E.D.]

...which means we know that 15ish years prior to when we checked, there wasn't anybody over there transmitting artificial radio signals in our direction powerful enough to reach us.

That is certainly more than not knowing that. But what we probably ought to start off doing is just gathering as much information about those nearby systems as our current tech level and human ingenuity allows, instead of looking for one specific thing all over the universe (eg: SETI). We are at the point where we really don't even know what we don't know yet. But if we find something interesting, (which may or may not be life related), those are the systems we are capable of sending probes to. You're absolutely right that looking for interesting things hundreds of light years away isn't liable to be very productive until we have the capability of traveling there in a reasonable amount of time.

Spain didn't travel to the New World until after they'd found and colonized the Canaries. Portugal didn't sail straight to China on the first try. They explored the coast of Africa, and in the process worked out how the winds and currents in that area could help them go further faster. We definitely should be concentrating on things that are on the outer edge of what we know how to reach today.

Again

[argStyopa]

Not sure how many times it has to be said: our ability to detect planets is RUDIMENTARY at best, limited to large, heavy, and/or close-in planets that happen to be precisely ecliptically aligned with ourselves.

To take any data based on what we have today and extrapolate "to the rest of the universe" is just silly.

Re:You Cannot Get Something From Nothing.

[tnk1]

Most supermodels do not starve themselves. They actually have genetics that are simply that good. And many of them are actually required to be athletic these days. Your Victoria's Secret models of the past used to be curvier. Now they are more athletic by contract requirement. That doesn't make then unhealthy and probably makes them more healthy.

They're also rich. Which should overcome any issues with their ability to birth and raise offspring.

So, yeah, a supermodel is a very good choice for our biology.

You might be thinking about the more run of the mill high fashion runway models, and yes, some of them resemble Holocaust survivors. I can't say that type has ever appealed to me.

Re: Where is everybody?

[Dunbal]

What, even Todd Hunter?

Re:We may not be alone in the universe

[fche]

can confirm

I draw the opposite conclusion...

[laugau]

You're all arguing about whether a finite number of worlds exist in infinite space... but you buried the lead. According to the logic, we ourselves don't exist. There is a 0 percent chance that we are present in the universe, that we ever existed or, in fact, that we ever will exist.

Kind of depressing, really.

Re:You Cannot Get Something From Nothing.

[Empiric]

Yes, you have absolutely no evidence of a Prime Mover.

That in no way means there is no evidence. It just means you haven't, or refuse to, do a simple Google search on the matter.

Here's a few terms to try for a great deal of evidence:

"holographic universe"
"Everett Interpretation of Quantum Mechanics"
"testimonies of religious experience"
"Lancet peer-reviewed NDE study"
"religious persecution of Rome"
"prophecy fulfillment"

Direct recent study link if that's too much work.

Yes, we could do the standard thing and watch you equivocate "evidence" to mean "proof" (it doesn't, nor am I proposing to force-convert you as the inescapable logical consequence of being provided "proof"), or try to ludicrously narrow the scope of the subject at hand (e.g. I don't find "Prime Mover" in these searches at all!), or claim that if you have an alternate explanation for an item of evidence, it then ceases to be evidence (it doesn't, in this or any other context whatsoever).

All are commonplace. Neither are interesting or philosophically sound. Neither alters the fact I can simply wait until you are unable to continue this, or any, argument--according to you yourself. I suggest a re-evaluation of strategy.

Is there life out there?

[Jason Levine]

I'd say the chances for life being out there are very good given how big the Universe is. To quote Yakko Warner:

It's a great big universe
And we're all really puny
We're just tiny little specks
About the size of Mickey Rooney.
It's big and black and inky
And we are small and dinky
It's a big universe and we're not.

And we're part of a vast interplanetary system
Stretching seven hundred billion miles long.
With nine planets and a sun; we think the Earth's the only one
That has life on it, although we could be wrong.
Across the interstellar voids are a billion asteroids
Including meteors and Halley's Comet too.
And there's over fifty moons floating out there like balloons
In a panoramic trillion-mile view.

And still it's all a speck amid a hundred billion stars
In a galaxy we call the Milky Way.
It's sixty thousand trillion miles from one end to the other
And still that's just a fraction of the way.
'Cause there's a hundred billion galaxies that stretch across the sky
Filled with constellations, planets, moons and stars.
And still the universe extends to a place that never ends
Which is maybe just inside a little jar!

Meaningless

[holophrastic]

That there once, a billion years ago, was a civilization, a few million light-years from here, is totally meaningless. Like so many mathematical conclusions, it misses the point. What we care about is an advanced civilization here and now, where here is somehow reachable either physically or communicably or visibly. And we don't care about plants and worms and single-celled organism either.

The math falls apart quickly when you then divide by time.

Additionally, the spark of life is still somewhat of a mystery. There's no guarantee that a habital world will eventually develop life just because it is habitable.

Keep dividing folks. A Trillion Billion isn't difficult to reach. Anyone who's written a poorly-considered sql join statement knows that all too well.

Re:You Cannot Get Something From Nothing.

[MightyMartian]

I'm not equivocating, because most of what you refer to is either garbage or highly contested philosophical interpretations.

I'm sorry. You don't have a Prime mover to show me, and you cannot even demonstrate that one is necessary.

I don't need an alternative explanation. That isn't how it works. It's your job to come up with a testable verifiable and falsifiable test for your Prime Mover. That is your job, so produce the paper and the data that shows the Prime Mover exists. Don't give me speculative papers about a holographic universe and a bunch of religious mumbo jumbo, because you're right, I absolutely and completely reject anything that isn't real, verifiable evidence.

You're a century-and-a-half behind the times

[Cajun Hell]

That might have been suggestive to people in 1858. Ask someone in 1860, though, and they'll tell you about a clever little trick that Mother Nature has up her sleave (evolution).

We don't know how life starts (though we have our suspicions) but we know that once you have it booted up, it'll get as complex as the situation warrants.

proof of chaos theory

[epine]

Drake equation = batshit attractor

Re:And how does that help us?

[Dorianny]

Define "poor". Poor from today, look very much like upper middle class from 1960. We have TVs and Microwave Ovens, cars that last a long time, and housing that is more efficient.

Saying "help the poor" is always a noble cause, but the definition changes over time to the point where the term itself is meaningless.

The Upper middle classes in the 1960's could afford the best Education, Health care and desirable real estate locations. Absolutely NOTHING has changed. The poor still only have access to sub-par education, health-care and living locations

Re:And two months ago, a completely different outc

[Dread_ed]

I prefer my own quote:

It's empty, but that just because we haven't finished growing into it yet.

Re:You Cannot Get Something From Nothing.

[Dread_ed]

You just said "because everything I have ever observed is based on cause and effect, I can only imagine a creator that is constrained by the same rules of cause and effect."

That's like saying "We can simulate higher base number systems here inside the computer, but everyone knows that everything, everywhere, and everywhen is only made from ones and zeros."

Fluke is fluke

[Tablizer]

calculated that human civilisation is only unique if the odds of a civilisation developing on a habitable planet are less than one in 10 billion trillion. "One in 10 billion trillion is incredibly small.

By what standards? What law says most probabilities are supposed to be small?

Re:Reverse Calculate Average Lifetime of Civilizat

[bloodhawk]

given we have no data points or anything to base a paper on the estimated lifetime of a technological civilization I would say any paper written on it would be a pathetic joke not interesting.

Obligatory XKCD on Drake Equation

[jma05]

https://xkcd.com/384/

We might be "the ancient ones" of our universe

[Varcain]

There was a /. article some time ago which stated, that judging by element composition of our universe we are still before the largest eruption of element-rich planets like Earth. Which means we might as well be THAT ancient alien civilization which aliens of the future will be researching. This could basically give the answer to Fermi's Paradox. We may well be the first ones out there. Given there were over 4 billion species on our planet throughout our history and how many of these evolved intelligence? And out of these how many are physically capable of creating a Civilization (like having limbs to create and use tools, which Dolphins, another intelligent species don't have for example). Another scary thought is how many times our species were on the brink of extinction before we created any civilization.

Re:And how does that help us?

[Ionized]

food insecurity & inability to afford basic healthcare are two pretty big red flags.

living paycheck to paycheck, renting instead of owning your own place, those are another two big ones.

that's poor. owning a TV and microwave oven does not change the fact.

Biogenesis

[technocrattobe]

It comes down to biogenesis. If the genesis happened by chance or its a contentious process and new life forms are in the process of making even today.

Re:Simulation argument

[david_thornley]

3) Interstellar travel is way impractical, and we have a lot of science and technology to develop before we can even recognize the physical basis of their Internet-equivalent. In a million years, we can be collective n00bs with ancient and incredibly advanced races trying to teach us nettiquette.