Space Cadet Will Hutton is sadly misinformed.

[UndercoverElephant]

As a mere BTW, the observation difficulties in Quantum Physics are due to the entropy of information.

You think so do you? No "in my opinion, not based on science or reason". Nope, you confidently proclaim that you already know the correct solution to "the observation difficulties in QM". The fact that there's 20+ metaphysical interpretations of of QM, none of which are falsifiable or supportable with empirical evidence, apparently makes little impact on you.

So please tell me. Which interpretation of QM is correct and, more importantly, how the hell do you think you know???

I've already stated which interpretation I tentatively go for: Henry Stapp's reworking of the Wigner version of the original Von-Neumann interpretation. I've also stated that my reasons for prefering this interpretation are due to things like ethical and aesthetic considerations, parsimony with respect to the rest of my belief system, and personal experiences. If you are anything like most of the internet expertz on QM I run into, you don't know very much about the different interpretations of QM but you think you understand the implications of QM anyway. I'll be pleasantly surprised if I am wrong about this, because this is one of my favourite topics and I'll happily discuss it until the cows come home.

[UndercoverElephant]

The problem with this explanation is that if intelligent life is common, even if it is distant, then we ought to have found signs of it by now. This is because once it appears, unless it always destroys itself soon after, it ought to hang around for a long time. So unless you think we are miraculously the first intelligent life to evolve in the galaxy even though life is common, or you think that intelligent life is always a flash in the pan like humans are likely to end up being, then I don't think the explanation works.

Any stable, sustainable high-tech civilisation should have been sending out EM and other transmissions for a very long time - long enough for evidence to have arrived at the Earth and be detected by us. The silence is deafening.

I'm not so sure about this - it seems to me that the distances between intelligent life forms, assuming they are to exist outside Earth, would be great enough to make it very difficult for them to establish each others' presence.

That's not true if these civilisations have any staying power. If humans weren't trashing the Earth, we could establish a civilisation that lasted for a hundred thousand years. By that time, the signals we have been leaking into space for the past one hundred or so years will have had time to reach every corner of our Galaxy.

Even if we found some kind of signal, the chances of actually ever "meeting" aliens, or even communicating with them, seem pretty much zero, given the limitations imposed by the distances.

That is quite likely to be true, yes. Detecting them is one thing. Actually meeting them or establishing two-way communication is a whole other ball game.

For me, the question of extraterrestrial intelligent life is one of the least interesting areas of scientific speculation - because I don't see why its discovery would tell us anything fundamentally new about the universe.

The discovery of any sort of non-terrestrial life would, I think, be the most important discovery in human history.

[Ludwig]

I'm not so sure about this - it seems to me that the distances between intelligent life forms, assuming they are to exist outside Earth, would be great enough to make it very difficult for them to establish each others' presence.

That's not true if these civilisations have any staying power. If humans weren't trashing the Earth, we could establish a civilisation that lasted for a hundred thousand years. By that time, the signals we have been leaking into space for the past one hundred or so years will have had time to reach every corner of our Galaxy.

True, but I tend to the view that any civilisation that establishes a means of destroying itself will do so, sooner rather than later.

I do think there is such a thing as a collective death-wish, and I wonder if all civilisations don't have it.

Even if we found some kind of signal, the chances of actually ever "meeting" aliens, or even communicating with them, seem pretty much zero, given the limitations imposed by the distances.

That is quite likely to be true, yes. Detecting them is one thing. Actually meeting them or establishing two-way communication is a whole other ball game.

For me, the question of extraterrestrial intelligent life is one of the least interesting areas of scientific speculation - because I don't see why its discovery would tell us anything fundamentally new about the universe.

The discovery of any sort of non-terrestrial life would, I think, be the most important discovery in human history.

I suppose it depends on what is important to one personally, as much as anything.

I feel that if there is a "next level" of human discovery, it involves the discovery of our own nature rather than of something new "out there" in the universe. But that's just a personal view and at bottom entirely speculative.

[UndercoverElephant]

I'm not so sure about this - it seems to me that the distances between intelligent life forms, assuming they are to exist outside Earth, would be great enough to make it very difficult for them to establish each others' presence.

That's not true if these civilisations have any staying power. If humans weren't trashing the Earth, we could establish a civilisation that lasted for a hundred thousand years. By that time, the signals we have been leaking into space for the past one hundred or so years will have had time to reach every corner of our Galaxy.

True, but I tend to the view that any civilisation that establishes a means of destroying itself will do so, sooner rather than later.

That's the whole point of [this branch of] the discussion. That's why the subject came up in the first place. The person who brought it up agrees with you, but I think there might be other explanations as to why we seem to be alone in the cosmos.

I do think there is such a thing as a collective death-wish, and I wonder if all civilisations don't have it.

The problem is not death-wish on the scale of the individual. It's the opposite. And civilisations proceed according to the decisions of billions of individuals. This leads to what looks like a death-wish on the scale of the civilisation.

I feel that if there is a "next level" of human discovery, it involves the discovery of our own nature rather than of something new "out there" in the universe.

That's not new, at least not on the scale of the individual.

[vtsnowedin]

Get real people. If you assume that an episode of "I love Lucy" was broadcast out into space in 1950 it would now be just 61 light years away from us in the direction the planet was pointed at the time of broadcast. The signal no mater how concentrated when it left earth or the Van Allen belts would now be spread over several light years of space and be nothing but static.

[RogueMale]

I think the real explanation is in the distances involved. In the 200 to 400 billion stars in our galaxy there are probably millions of planets that can and probably do support life as complex as our own world but that life is isolated from us by the space between us. Consider that the milky way is some 100,000 light years in diameter and we can only see with the naked eye some 1000 light years. Then consider that the closest group of stars, our next door neighbors, are 4.3 light years from us and that the fastest we have ever achieved with a space vehicle is a puny 150,000 miles an hour, a tiny fraction of lights 186,000 miles per second, you get that sending our fastest runner to the neighbors for a cup of sugar will take about 40 million years each way. This is why science fiction writers always go to warp drives or wormhole jumping to get us together with beings from another world.
We are stuck in the solar system we are in and can't get out of it far enough to matter and we are on the only water and atmosphere rich planet in our solar system so we should take better care of it as it's the only one we are ever going to get.

This has already been considered. There are two counter-arguments. One is that extraterrestrials can communicate by electromagnetic radiation, possibly beamed at stars likely to support life, so they don't need to come here. The other is that they send unmanned self-replicating probes spread out in all directions. There's no evidence of either; there ought to be.

[RogueMale]

That's not to say that the universe we experience is ground reality. It might be a simulation, running on a computer in the real universe, guided by the hand of a deranged Perl programmer.

IMO computer models of reality are off the mark, and an example of the understandable, but misguided, tendency to model reality on the latest technology: "The universe is not fully understood, and hugely complex, so if we model it on the most complex thing we DO understand, we'll make progress."

...

The universe is no more made up of bits and bytes than it is made up of patterns of coloured ink on gloss paper.

That's not quite what I meant. The Perl programmer was an XKCD reference (http://xkcd.com/224/). What I did mean was that this might not be the real universe: it might be a simulation implemented (we know not how) on a "computer" running in a universe we can't even imagine. And my gut feeling is that, if that is the case, consciousness belongs to the real universe, rather than created out of information on the simulated one (which we're accustomed to thinking is real), which is why it doesn't seem to be derivable from any accepted physical theory. Though that doesn't really get us very far.

[RogueMale]

Yes, there's two issues bound up here, or actually three because, as you suggest, this is all closely linked to what you believe about quantum mechanics.

Unlike yourself, I am sympathetic to the strongest of the anthropic principles - the SAP and the PAP. The claim that the cosmos had to have the laws of physics and values of physical constants that it does is deeply controversial, and I see no reason to believe it. It looks to me like the chances of a randomly-created cosmos being conducive to the existence of stable stars and the development of life are almost zero. That leaves me choosing between the idea that all possible physical cosmoses actually exist, or some other explanation (several of which are possible at this point).

Another argument against the Anthropic principle is that it can be applied to things we already have perfectly good explanations for. E.g. we could say that the reasons that planetary orbits are not square with the sun close to one of the corners is because if that was the case, we wouldn't be here to observe it. Or we could just point out that Newton's law of gravity requires them to be ellipses with the sun at a focus, and that Newton's law is just GR at the classical limit. So why not just say that there's a reason the strength of gravity times the age of the universe is close to 1 (in natural units) is because of a theory we haven't worked out yet?

But it is consciousness which really tips me towards the PAP. My prefered interpretation of QM is Von-neumann/Wigner/Stapp, but this is backed up purely by non-scientific personal experiences, including some which most people would categorise as paranormal. This isn't much use to you or anybody else, but justifies me in believing what I happen to believe.

I'm unfamiliar with that interpretation.

My preferred interpretation is Everett's Many Worlds, but please note that while this means that all possible universes coexist, they all would have exactly the same laws of physics.

My views are probably influenced by stronger conclusions about consciousness than you have come to. I wouldn't just categorise this as "we don't currently know." I'd categorise most of the questions involving consciousness as fundamentally unanswerable by empirical science and therefore either totally unanswerable or answerable only via paranormal/mystical means. I'd say physicalism is logically false if you accept the existence of consciousness.

I've thought about it quite a lot, and while I have ideas of my own, my views are fairly close to those of David Chalmers.

[UndercoverElephant]

The problem with this explanation is that if intelligent life is common, even if it is distant, then we ought to have found signs of it by now. This is because once it appears, unless it always destroys itself soon after, it ought to hang around for a long time. So unless you think we are miraculously the first intelligent life to evolve in the galaxy even though life is common, or you think that intelligent life is always a flash in the pan like humans are likely to end up being, then I don't think the explanation works.

Any stable, sustainable high-tech civilisation should have been sending out EM and other transmissions for a very long time - long enough for evidence to have arrived at the Earth and be detected by us. The silence is deafening.

If you merge Drake's Equation with Sir Fred Hoyle's one-chance hypothesis and then look at how far we've managed to progress with all of our natural resources then it doesn't seem so strange that most civilisations fail to become inter-Galactic.

We don't need inter-Galactic. We are talking intra-Galactic here, which is more than enough given the relative size of our home Galaxy to anything else in in this corner of the Universe.

[RogueMale]

I also do not buy your suggestion that physicalism is incompatible with consciousness. Consciousness could adequately be described as a self-programming feedback system the basic principles of which are broadly understood. It requires no elements beyond the physical to make me me, it simply requires that I accept that I have no essence beyond my physical form.

No, or at least no one's come up with a convincing argument for that. It might explain the external signs of consciousness in others (how they might behave if they saw red, heard a minor chord, or felt itchy), but it doesn't explain the internal symptoms (what it's like to see red, hear a minor chord, or feel itchy).

Also, there was a guy called Knut Nordby, who died a few years back. He was an expert on colour vision, despite being unable to see any colours at all (just monochrome). He said he had absolutely no idea what it was like to see colours, despite having thought long and hard about it.

[UndercoverElephant]

Yes, there's two issues bound up here, or actually three because, as you suggest, this is all closely linked to what you believe about quantum mechanics.

Unlike yourself, I am sympathetic to the strongest of the anthropic principles - the SAP and the PAP. The claim that the cosmos had to have the laws of physics and values of physical constants that it does is deeply controversial, and I see no reason to believe it. It looks to me like the chances of a randomly-created cosmos being conducive to the existence of stable stars and the development of life are almost zero. That leaves me choosing between the idea that all possible physical cosmoses actually exist, or some other explanation (several of which are possible at this point).

Another argument against the Anthropic principle is that it can be applied to things we already have perfectly good explanations for.

That doesn't mean it doesn't apply in certain cases we don't have explanations for. It's an argument, but it's not very powerful if you think you've got reasons to believe something else.

But it is consciousness which really tips me towards the PAP. My prefered interpretation of QM is Von-neumann/Wigner/Stapp, but this is backed up purely by non-scientific personal experiences, including some which most people would categorise as paranormal. This isn't much use to you or anybody else, but justifies me in believing what I happen to believe.

I'm unfamiliar with that interpretation.

I can recommend "Mindful Universe" by Henry Stapp.

My preferred interpretation is Everett's Many Worlds, but please note that while this means that all possible universes coexist, they all would have exactly the same laws of physics.

Please enjoy....

http://www.rationalskepticism.org/philo ... 203c01df8e

I've thought about it quite a lot, and while I have ideas of my own, my views are fairly close to those of David Chalmers.

I like Chalmers, mainly because he's the perfect antidote to Daniel Clement Dennett. If you like Chalmers and don't know Stapp, then you might like Stapp more.

[vtsnowedin]

This has already been considered. There are two counter-arguments. One is that extraterrestrials can communicate by electromagnetic radiation, possibly beamed at stars likely to support life, so they don't need to come here. The other is that they send unmanned self-replicating probes spread out in all directions. There's no evidence of either; there ought to be.

So they have electromagnetic radiation that travels faster then the speed of light? Or they have self replicating probes that self replicate at 100% efficiency?
I have a bridge to sell you that is the deal of a lifetime!

[JavaScriptDonkey]

As a mere BTW, the observation difficulties in Quantum Physics are due to the entropy of information.

You think so do you? No "in my opinion, not based on science or reason". Nope, you confidently proclaim that you already know the correct solution to "the observation difficulties in QM". The fact that there's 20+ metaphysical interpretations of of QM, none of which are falsifiable or supportable with empirical evidence, apparently makes little impact on you.

So please tell me. Which interpretation of QM is correct and, more importantly, how the hell do you think you know???

I've already stated which interpretation I tentatively go for: Henry Stapp's reworking of the Wigner version of the original Von-Neumann interpretation. I've also stated that my reasons for prefering this interpretation are due to things like ethical and aesthetic considerations, parsimony with respect to the rest of my belief system, and personal experiences. If you are anything like most of the internet expertz on QM I run into, you don't know very much about the different interpretations of QM but you think you understand the implications of QM anyway. I'll be pleasantly surprised if I am wrong about this, because this is one of my favourite topics and I'll happily discuss it until the cows come home.

Are you one of those people who claim to understand Quantum physics but can't do the Quantum Mechanics? The sort of chap who discusses the metaphysical ramifications of Shrodinger's cat but can't derive from his time-dependant equation? The Internet is full of those.
QM stretches my math beyond breaking point so I generally STFU and let proper Quantum Physicists do the talking. Are you a quantum physicist? It is taught at Sussex...

But nope, my BTW was based firmly on Information Theory. I do not claim to 'know', I just go for the solution that doesn't involve belief or mangled definitions of consciousness.

If I have to choose between Shannon or Stapp then, after laughing like a drain at Stapp, I'll choose Shannon.

[JavaScriptDonkey]

The problem with this explanation is that if intelligent life is common, even if it is distant, then we ought to have found signs of it by now. This is because once it appears, unless it always destroys itself soon after, it ought to hang around for a long time. So unless you think we are miraculously the first intelligent life to evolve in the galaxy even though life is common, or you think that intelligent life is always a flash in the pan like humans are likely to end up being, then I don't think the explanation works.

Any stable, sustainable high-tech civilisation should have been sending out EM and other transmissions for a very long time - long enough for evidence to have arrived at the Earth and be detected by us. The silence is deafening.

If you merge Drake's Equation with Sir Fred Hoyle's one-chance hypothesis and then look at how far we've managed to progress with all of our natural resources then it doesn't seem so strange that most civilisations fail to become inter-Galactic.

We don't need inter-Galactic. We are talking intra-Galactic here, which is more than enough given the relative size of our home Galaxy to anything else in in this corner of the Universe.

Even less, how about a simple hop over to Alpha Centauri C? It's taken us 35 years to get to the heliopause...only another 40,000 or so and we might get close to another star. Assuming that cosmic radiation outside our solar system is survivable of course. I doubt our current EMF radiation output would stand out against the background hum of our star or even the constant buzz of our atmosphere. I'm not that far from the transmitter and sometimes Radio4 is a bit dodgy.

Hoyle puts a very real dampener on deep space exploration that should be familiar to you - resource limitation.

[AndySir]

To all who took issue with the physical definition of consciousness: if you were a self-programming system with feedback and sensory input how would your awareness of the universe be different. To twist Pascal's declaration into a question, what it is that requires more?

It sounds like people are extending consciousness to include quasi-religious ideas of self or soul, so for the purposes of clarity perhaps we should say that it is awareness of one's surroundings, self and mental processes. If we are no more than this we shall have the proof through AI research in time, though we may not yet understand the mechanisms of our own brain.