Why everyone should stop folding and go SETI

[Simon F]

Also referring to the number of species on earth is irrelevent. Those all share a common ancestry, and with the exception of human beings, none of them are "intelligent", that is, smart enough to develop technology, written language, etc

There is an interesting commentry on this in "The Science of Discworld" which, ironically, has nothing to do with 'science' on Pratchet's "world" but with theories of our own planet.

It points out that there has been ample time for several intelligent species to have evolved but the earth has been hit by numerous mass extinction events that wiped out 90-odd percent of the life forms each time!

As for us being the only intelligent species - isn't there a good chance we killed off another, i.e. the Neanderthals ?

 

[Simon F]

Reasons SETI should be ditched:
We won't find alien. Why? Well, scanning radio data from cosmos are unlikely to ever find anything but cosmic noise. First of all, what is the likelyhood that aliens would be using radiowaves? Will even humans use radiowaves in 100 years?

I'd say yes... but as for aliens, what we should be doing is looking for huge chalkmarks orbiting distant stars showing where to tap into unprotected inter(stellar)net systems.

 

[DemoCoder]

But Fred, the handwaving argument that "we have immense numbers of X" is irrelevent without context. if the probability of life forming is something like 1 in 10^20, maybe things work out. If it's 10^40, it becomes rare. You just can't take any large number X and wave your hands over it to solve any scenario.

We all know what the probability is of all the air molecules in my room moving to one corner . Can I just wave my hands and say "given the number of planets in the universe, it must have happened atleast once!!"

In fact, we do not know how many pathways lead to self replicating molecules. It could be that there is an unfathomly huge state space, and only a single sequence of moves which can arrive at a universal replicator.


We have reason to hope, because as shown by research in cellular automata, atleast with respect to idealized 1D and 2D automata, there are several rulesets which exibit universality (under the principal of computation equivalence), not just a single one, and there are several initial states which can lead to self replicating structures (e.g. glider guns)

We have only one ruleset (natural laws), but it may be that more than one initial condition (planet environment) can lead to evolution of life.

But this is utter and complete speculation. As of right now, we know of no such conditions. Therefore, speculation as to the existence of life, let alone ET intelligences, is borderline science, something CSICOP would call "gray" science.

People seem to have a deep seated need for the universe to not be devoid of life, an emotional attachment to the idea. I grew up on science fiction and sci-fi as well, and always dreamed of interstellar travel, aliens, et al, but the fact that I dream of it and wish it, does not make it neccessary that it exists.

I have fundamental doubts about the ability to travel faster than light. I'm placing my bet that any future interstellar travel will simply use vast amounts of time, with extremely small probes, at high velocities, with any conscious observers, mechanical, rather than biological, to the point of software. (think ship that weigh 1kg down to 1gram)

As of now, the only way we know of travel requires vast amounts of mass and energy, and I do not expect this to change, or that we will find ways to "cheat" and somehow steal a few exa-watts of power. All known methods currently rely on negative energy and exotic matter, and the amount of such things usually exceeeds the mass-energy requirements for classical travel.

 

[jvd]

My feelings are basicly. Hey we are here. So if we managed to exist then someone , some where , some time existed or exists. If it was just luck i'm sure the luck held out for others. If it was a god well I'm sure he wouldn't just make one race and then go play pong for the rest of time.

 

[K.I.L.E.R]

DC, you still fail to give any evidence for your argument.

 

[Humus]

The point he's trying to make is that those claiming the existance of extraterrestial life exist are the ones that need to come forth with proof. Neither me or DC makes the claim that such life cannot exist, but we both are sceptical until proof is provided. We don't have a case to prove, those who claim that such life must exist need to come forth with proof.

 

[K.I.L.E.R]

I believe both sides need to come forth with proof to make any conclusion.

 

[Humus]

The point was rather that there is no ultimate conclusion to be made until we have any real data to base a conclusion on.

 

[K.I.L.E.R]

The point was rather that there is no ultimate conclusion to be made until we have any real data to base a conclusion on.

Finally you understand one of the points I was making since page 2.
All we have are shaky theories.

I was also suggesting that people leave an open mind.

I wouldn't be surprised if I met a female version of myself on planet Vulcan.

 

[Deepak]

DC, the no of potential planets in the unverse is so GREAT that UNLESS the chaces are ZERO, it is VERY likely that there is life, there is intelligent life somewhere....

 

[London Geezer]

EXACTLY. if we managed to survive so far, then the chances of developing life, intelligent life, are > 0
therefore it is likely that somewhere and sometime in the universe, life has existed or is existing or will exist.

the chances that a planet similar to earth had pretty much the history of our one are not 0, therefore there is a chance a planet very similar to ours has existed or exists now, or will exist in the future.

will we ever communicate, or even see it? rather unlikely.

at the end it is like looking for God. this planet would be so far away it would probably be easier for us to "prove" that there is some kind of god than to communicate with the people inhabiting the planet....

to the guy asking me what books he can find, i'll check the titles i have then get back to u. the specific book i was referring to is extremely interesting, rather easy on the brain (it does go a bit technical sometimes though), and has 9 very modern theories on the way we look at the universe and reality, touching the topics of black holes, time travel, possibility of extraterrestrial life, quantum multiverse and others, explained in detail. shame i can't remember the name of the book...

 

[Silent_One]

Fred wrote:

We have immense numbers (eg 18 orders of magnitude decimal places) that have to cancel exactly in order for our theory to work (eg for life to actually exist). We know they do, since we are here, and see it happen. Ultimately what has to give, is not the acceptance of the fact under current theory, but rather the actual theory itself. It has to be *Wrong*!

I too find it interesting that given that the probability of, say, "the Universe has a life (as we know it) supporting planet - 1 in 10^161" or "Probability estimate of the mininum set of the required 239 protein molecules for the smallest theoretical life - 1 in 10^119,879", are so extreme such that for all intents and purpose life should not exist....and yet...here we are. Indeed, the fact that we are here seems to refute the equations against life and support the idea that life elsewhere might exist.

 

[zidane1strife]

The point he's trying to make is that those claiming the existance of extraterrestial life exist are the ones that need to come forth with proof. Neither me or DC makes the claim that such life cannot exist, but we both are sceptical until proof is provided. We don't have a case to prove, those who claim that such life must exist need to come forth with proof.

Proof?!? We shall give ye proof, the "Terrestrial Planet Finder", and the "Planet Imager"... Life Finder... their power, is likely to be sufficient... so it is only decades that stand before us... and like all barriers they shall fall in due time...

A goal of Terrestrial Planet Finder (TPF) is to search for signs of the large-scale effects that life would have on a planet's chemistry. By analyzing the colors of infrared radiation detected by TPF, astronomers can search for atmospheric gases such as carbon dioxide, water vapor, and ozone. Together with the temperature and radius of the detected planets, this information will allow astronomers to determine which planets are habitable, or even whether they may be inhabited by rudimentary forms of life.

The findings of Terrestrial Planet Finder would guide a possible subsequent mission called Life Finder. Like its predecessor, Life Finder would consist of an array of telescopes flying in formation. The telescopes would combine infrared light to produce high-resolution spectra of the atmospheres of distant planets.

Scientists would use this information to search more closely for markers of biological activity, such as seasonal variations in the levels of methane and other gases, changes in atmospheric chemistry and spectral variations in the dominant biomass.

On another note... while perusing the web...

NASA's Hubble Space Telescope precisely measured the mass of the oldest known planet in our Milky Way galaxy. At an estimated age of 13 billion years, the planet is more than twice as old as Earth’s 4.5 billion years.

How is that possible, the latest data shows the universe at around 13.7Billion years of age.

The new Hubble findings close a decade of speculation and debate as to the true nature of this ancient world, which takes a century to complete each orbit. The planet is 2.5 times the mass of Jupiter. Its very existence provides tantalizing evidence that the first planets were formed rapidly, within a billion years of the Big Bang, leading astronomers to conclude that planets may be very abundant in the universe....

...it is unlikely that any civilization witnessed and recorded the dramatic history of this planet, which began at nearly the beginning of time itself.

Strange... this thing is in our own galaxy!!!

 

[pascal]

Reasons SETI should be ditched:
We won't find alien. Why? Well, scanning radio data from cosmos are unlikely to ever find anything but cosmic noise. First of all, what is the likelyhood that aliens would be using radiowaves? Will even humans use radiowaves in 100 years?

I'd say yes... but as for aliens, what we should be doing is looking for huge chalkmarks orbiting distant stars showing where to tap into unprotected inter(stellar)net systems.

Do they use TCP/IP ?

My guess life is rare and sparselly distributed in space and time.

 

[Natoma]

Also referring to the number of species on earth is irrelevent. Those all share a common ancestry, and with the exception of human beings, none of them are "intelligent", that is, smart enough to develop technology, written language, etc

That's today Democoder. You have absolutely no idea if intelligent life has evolved on this planet in the past. Look at us. We have evolved our level of intelligence in a geologic blip, i.e. roughly 100,000 years.

You don't think it's possible that other species could have arisen with our level of technology, if not higher (think how much further we'd be today if we didn't have the "dark ages" or the bubonic plague in the 13th century which knocked out 1/3 of Europe population, or the centuries that went by where the church didn't allow anyone to learn to read) during the 2 billion year history that life has existed on this planet?

If we had the technology to up and leave this world today, or if we obliterated ourselves in a nuclear war, in a few million or so years, everything as we know it would be gone and the surface completely transformed. You wouldn't even know we were here.

You make ridiculous assumptions that simply defy logic considering what we've seen in not only our species, but life on this planet in general in the past few billion years. Stop it!

 

[Natoma]

Yes, but they are gas giants or orbiting the wrong kind of stars. And even if they were the right kind of stars, you need sufficient amounts of carbon, oxygen, nitrogen, and other higher elements (besides helium or hydrogen), and these only exist if you've had a few supernovas in the areas spreading such material.

You're assuming that life has to be carbon based and life in a biosphere like our own. Life has shown itself capable of rising from anything. It could be silicon based for all we know.

And even if you have the right kind of star, life has to start at the right time. Early or late in the stars life, and it's too inhospitable. There is a "window" in the typical Sun-like star's main sequence where the right environment can exist.

Indeed. However, considering life as we know it didn't form on this planet until 2 Billion years ago, roughly 2 Billion years after the earth formed and 1 Billion years after the sun first lit, I'd say that's a pretty huge window of opportunity would you not?

Estimates have been done on the number of main-sequence Sun-like stars in the universe combined with probability of supernovas, and those just compound the already unlikely probability of abiogenesis.

And even though the probability is low, with the vast number of planets we suspect is out there, that leaves thousands, if not millions, of possible life-bearing candidates.

Frankly you're just a pessimist.

 

[Humus]

DC, the no of potential planets in the unverse is so GREAT that UNLESS the chaces are ZERO, it is VERY likely that there is life, there is intelligent life somewhere....

I suggest you reread DC's posts and come back once you have understood them. The "numbers are sooooo greeeat so it gotta weigh up everything but zero" kind of reasoning is simply just false. 10^22 doesn't weigh up more than 1/10^22. Plain simple math. If we're talking about probabilities that are close to infinitismal and multiply it with something close to infinity there's nothing saying that it gotta even out. 10^100 tries on a probability of 1 in 10^103 likely won't succeed.

 

[Humus]

Proof?!? We shall give ye proof, the "Terrestrial Planet Finder", and the "Planet Imager"... Life Finder... their power, is likely to be sufficient... so it is only decades that stand before us... and like all barriers they shall fall in due time...

Sure. Come back when the proof is presented. Until then ...

 

[Bigus Dickus]

DC, I didn't say you were a creationist, but rather that you sounded like one. Semantic difference maybe, but one would be meant as an insult and the other is not... and I didn't intend it as an insult. In return though, I see you've lumped me in with all the alien abducted God fearing tin foil hat wearing nut jobs. Thanks!

You make a good point... we have little in the way of data on how unlikely the formation of life is given the proper environment. That there are other Earth-like planetary environments is hardly debatable. Whether the existance of life on them is.

You take a lack of data and assume that the probability of life forming is exceedingly low... with a complete lack of data supporting that assumption. I and others assume the probability is rather high, again with a complete lack of data supporting our assumption.

Sure... if we are positing that the existence of life is high the burden of proof should be on us to find it. I believe advances in astronomy will find those telltale singns if they do in fact exist within my lifetime. But for now, there is no means available to gather that proof. We are both speculating in a vaccuum of information.

What we do know is that the number of habitable planets in the universe is very likely extremely high. What we do not know is the likelihood of life forming in such an environment. You use numbers like 10^40, but those have no real meaning. They are absolute shots in the dark with no factual basis.

So what it comes down to is akin to betting on a sporting event. You like one team, and I like the other, but in on way am I claiming it's an absolute certainty that one team will win.

 

[zidane1strife]

Sure. Come back when the proof is presented. Until then ...

Come back? Ye shall be a fellow witness to this discovery...
The clock is ticking...