Is SETI worth it?

[Polux]

I'm one of those who think that we're probably not alone, as I voted in the other poll, but I've been growing more and more skeptical about the SETI project.
I assume their methods are OK; I just think it is highly unlikely that we will find anything that way, or any other way for the matter. Then I consider it to be a huge waste of time and resources.
Of course, nobody knows whether anything will be found, but still, I'm asking if you think it's worth it.
I both think that there's probably life out there, and that we'll never get in touch. Unless there's something to find in our own solar system (hardly intelligent life forms...).

[Ratman_tf]

I voted yes. SETI costs less to run in a year than Americans spend on fast food.

http://www.seti.org/about_us/faq.html

[Marian]

Well since 1994 (per Seti's site) it's been completely funded by private donations (a fact I wasn't aware of actually). I could comment that it's a better use for money than numerous other things, but that doesn't REALLY address the question.

Is SETI worth it? Yeah. I'd have to answer yes. I'm taking into account it's private money, so we don't have to say is it a better use of the money than X...because people are choosing to toss their money specifically into SETI. There's no reasonable assumption that they'd be tossing that money to another specific cause instead.

Assuming SETI finds...nothing, is it still worth it? Sure, because finding nothing is still information. Knowledge is good. Plus there's the potential for spin-off uses of technology or information they discover. I don't know if any has happened yet, but I know that NASA has 'paid' for itself numerous times over JUST in spin-offs that benefit humanity. So any spinoff benefits are a clear win.

Assuming SETI finds...something, is it still worth it? We may not be able to do anything with that information at this point in time. But the discovery alone would be worth it.

Astronomers learned much by looking at the heavens and asking questions, and things they learned have applications beyond pure discovery. Whether or not that is or will be the case with SETI, I don't know, but it seems a worthwhile private endeavor.

[Polux]

Originally posted by Marian

Assuming SETI finds...nothing, is it still worth it? Sure, because finding nothing is still information. Knowledge is good.

True, but in my opinion this information would not be of great value, thus not worth the effort (since I consider it most likely that SETI will find nothing).
Basically what we would learn is that if there's other intelligent life, it is awfully hard to find.

Originally posted by Marian

Assuming SETI finds...something, is it still worth it? We may not be able to do anything with that information at this point in time. But the discovery alone would be worth it.


Absolutely... if something is ever found, I will admit that it was worth it after all. I just think it too unlikely to bother.

Perhaps I should have asked differently: Would you put your own money on SETI? Or, do you think SETI will ever find something? This sounds more like what I was thinking when I created the poll. Because, as you say, the project might be worth it for other reasons, and I would have preferred to leave those other reasons out of the question. Too late for that now!

[Dancing David]

Given how little is costs to piggy back SETI, why not, we spend lots of money all the time on potentialy worthless research. The payoff is more or a spiritual one than any thing else.
I let my computer chrunch numbers for SETI@home.

THink of the money people give to the church, there is still no proof of god.

[Batman Jr.]

They do make the assumption that intelligent aliens will use radio waves for communication. It's even fallacious to say that if they're using another kind of technology, then it follows that they at one time used radio communication as it is the most primitive form of wireless communication. This sentiment posits that an alien's grasp of logical/mathematical constructs is similar or the same to that of a human's. A different kind of mind may find it easier to foment a technology that we would consider more complex and more arduous a task to foment a technology we would consider simpler. Even restricting our musings to the human race, we can see this principle illustrated quite vividly in autistic-savants.

[Marian]

Originally posted by Pólux


Perhaps I should have asked differently: Would you put your own money on SETI? Or, do you think SETI will ever find something? This sounds more like what I was thinking when I created the poll. Because, as you say, the project might be worth it for other reasons, and I would have preferred to leave those other reasons out of the question. Too late for that now!

Ooo yeah different question. Tough one too. If like I could designate the $3 to go to SETI or the presidental campaign...I'd pick SETI.

Or if SETI was going to shut down due to lack of funds and my tossing $5 in would help...I'd toss in $5.

But I don't currently financially support SETI. I do have a charity I donate to specifically (and have asked others to donate to specifically) that I personally and selfishly find more important to me.

Just as I'm sure if someone was making a choice between AIDS research or cancer research and SETI...the first two would generally win. So it's still kinda a tough question. :( Because between SETI and a big mac, SETI wins. ;)

As far as if I think SETI will ever find something...I really don't know. If I HAD to answer only yes or no, I'd answer yes. Not because I believe they'll find evidence of E.T.L. necessarily, but that they'll find SOMETHING of value to be more likely (just purely in opinion) than NOTHING of value. Just the search itself is of value, because I believe exploration is in many ways essential to our nature. Wanting to know what lies over the next hill is a part of the human condition, I think. :)

Still doesn't give you a clear answer. But if you asked 'If SETI doesn't find any evidence of E.T. presence/life...was it a waste' I'd answer no. Because I don't believe because an experiment fails that it's necessarily wasteful. And in this situation that conclusion would still be of value (especially if new/better technology develops) as well as any potential spin-offs.

But the short answer would be: I believe SETI to be of value, merely because of its mission regardless of what it does/doesn't find. (And because it's a scientific mission, I wouldn't believe it had the same value if, for example, they were paying people to hum 'OM' to 'reach E.T.s')

[CurtC]

Y'know, if a time traveller came to me and informed me that tomorrow, either a) SETI will find a signal from an alien race, or b) that God will part the clouds and announce to CurtC that he does, in fact, exist, I would place my wager with b). And that's saying something.

[scotth]

Originally posted by Pólux

True, but in my opinion this information would not be of great value, thus not worth the effort (since I consider it most likely that SETI will find nothing).
Basically what we would learn is that if there's other intelligent life, it is awfully hard to find.

If we do a pretty exhaustive search, and we find nothing at all.... that is pretty interesting information to me. It gives at some idea of the potential rarity of intelligence life in the universe, or at least our galaxy. Making any kind of contact with a civilization in even the nearest galaxy besides our own just about defies contemplation.

If we can develop the capabilities to detect just the radio leakage from a world only as developed as ours is today, i.e. not a deliberate transmission to us, we could really get a good idea if there life is common at all. If would could detect a similar civilization to what we have to a distance of even half the radius of the Milky Way, if intelligent life is common at all, we should be able to detect some.

We're not that good yet, but we are gonna get there any faster by not practicing. They are improving the process all the time. They can analyze so many more channels of data at the same time than they could just a few years ago.

I find it worth it.

[Batman Jr.]

But what if it's not life that's rare; what if it’s instead radio communication?

[vlix]

You guys might be interested in this article:

http://www.planetary.org/html/UPDATES/seti/Contact/debate/default.html

It's a debate between Carl Sagan and Ernst Mayr, discussing the possibility of intelligent alien life and SETI's chances of success.

I for one have voted 'yes' in the poll ;)

[Paul C. Anagnostopoulos]

Curt said:
Y'know, if a time traveller came to me and informed me that tomorrow, either a) SETI will find a signal from an alien race, or b) that God will part the clouds and announce to CurtC that he does, in fact, exist, I would place my wager with b). And that's saying something.
You would? Wow, that is saying something.

~~ Paul

[Rob Lister]

Right now, seti is like a blind man walking through the desert listening to each grain of sand for the sound of a sand flea. It won't always be that way. As technology improves, we'll discover more and more extra-solar planets that are in the right orbit around the right stars. These are the area's on which seti will focus. This assumes their 'listening' technology improves as well, of course.

[DangerousBeliefs]

Originally posted by CurtC
Y'know, if a time traveller came to me and informed me that tomorrow, either a) SETI will find a signal from an alien race, or b) that God will part the clouds and announce to CurtC that he does, in fact, exist, I would place my wager with b). And that's saying something.

Really? Even though you know intelligent life exists but that God may not?

I would say A is 100% more likely than B, given our current level of knowledge.

[CurtC]

I am almost certain that life exists elsewhere. I am also almost certain that God does not exist. But it seems to me that the chance that God exists is greater than the chance that there will be intelligent life in the teeny-tiny section of the universe that we can detect with radio waves, and that this life will be at the stage in its development that it might be sending clean radio waves at high power.

So I would be more surprised about a SETI success.

[Dancing David]

Originally posted by Batman Jr.
But what if it's not life that's rare; what if it’s instead radio communication?

That is of course a very goos question, howver the anwer is simple, because we can. I suppose part of it is the assumption that aliens might act as we do, but it is also easier for us to use our technology to look for similar technology.

If another civilization uses nutrino modulation, we won't be able to detect it.

I agree however that there is a huge amont of anthropic thinking about aliens life, I doubt we could communicate even if they were close.

[vlix]

Originally posted by CurtC
I am almost certain that life exists elsewhere. I am also almost certain that God does not exist. But it seems to me that the chance that God exists is greater than the chance that there will be intelligent life in the teeny-tiny section of the universe that we can detect with radio waves, and that this life will be at the stage in its development that it might be sending clean radio waves at high power.

So I would be more surprised about a SETI success.

According to some people, like Carl Sagan for example, the chances of there being intelligent life in our little corner of the universe are not that small at all. If I remember correctly (perhaps I don't), his take on the Drake Equation suggested relatively large numbers of alien civilizations in our galaxy alone, at any point in time.

[Rob Lister]

Originally posted by Dancing David


If another civilization uses nutrino modulation, we won't be able to detect it.


Then again, they might use telepathic communication. I'm not sure what such a discovery might mean for JREF.

If, however, they used nutrino modulation, is it not reasonable that they would have progressed to that technology through others, just as we have progressed through smoke signals to laterns, electrical, CW, AM, FM VHF, microwave and now to fiber?

The problem as I see it is that (even) we have only been visible in the radio spectrum for a hundred or so years. In another hundred or so we will likely again be invisible (assuming we don't remain technologically stagnent.

Perhaps the 'nutrino modulation' comment has more weight than its author knows.

[scotth]

Originally posted by vlix


According to some people, like Carl Sagan for example, the chances of there being intelligent life in our little corner of the universe are not that small at all. If I remember correctly (perhaps I don't), his take on the Drake Equation suggested relatively large numbers of alien civilizations in our galaxy alone, at any point in time.

There "could" be. The Drake Equation has a number of parameters that we can only guess at. But putting numbers in towards the optimistic end of reasonable does give that result.

[scotth]

Originally posted by Rob Lister


Then again, they might use telepathic communication. I'm not sure what such a discovery might mean for JREF.

If, however, they used nutrino modulation, is it not reasonable that they would have progressed to that technology through others, just as we have progressed through smoke signals to laterns, electrical, CW, AM, FM VHF, microwave and now to fiber?

The problem as I see it is that (even) we have only been visible in the radio spectrum for a hundred or so years. In another hundred or so we will likely again be invisible (assuming we don't remain technologically stagnent.

Perhaps the 'nutrino modulation' comment has more weight than its author knows.

I would disagree, I suspect we become more and more visible in the radio spectrum as time goes on. Unless we seriously misunderstand the laws of physics, there really isn't a realistic basis for a technology that could replace it.

Communicating with space craft, airplanes, radar (weather radar if nothing else) are tasks that radio waves are perfectly suited for.

[vlix]

Originally posted by scotth


There "could" be. The Drake Equation has a number of parameters that we can only guess at. But putting numbers in towards the optimistic end of reasonable does give that result.

Exactly. But i would say that even when using rather pessimistic values for the various parameters, the chances of there being intelligent alien life trying to contact us, are still quite a bit bigger than the chances of God parting the clouds ;)

[AtheistArchon]

- The way I see it, there are two opposing sides to this issue.

- The first thing to consider is that we have a tight, coherent bundle of knowledge and science that says "wow, we know a lot about physics and radio waves and light, and communicating at FTL speeds just doesn't appear to be possible". For a majority of skeptics (here anyway, IMO), myself included, we listen to this voice quite often. It's a voice that says hey, this kinda sucks, but it's what we're seeing. That's the nature of skepticism and freethought after all.

- Then again, there's another thing to consider: immediately preceeding every great scientific breakthrough, there has been the same above voice. :D And keep in mind, we're newborns in the universe. This is the kind of thing I like to say I have faith in... that we'll continue to advance and break barriers. That doesn't mean I'm telling anyone it's the truth, or that my faith means it automatically has to happen. My faith is hope. And I hope I'm right.

[drkitten]

Originally posted by scotth
[B]

I would disagree, I suspect we become more and more visible in the radio spectrum as time goes on. Unless we seriously misunderstand the laws of physics, there really isn't a realistic basis for a technology that could replace it.
/B]

Well, I'm really glad that I'm living in the early 21st century, where the possibility of us seriously misunderstanding the laws of physics has finally been eliminated. It's so nice to know that we're in the final lap of this rat race we call "science" and we finally have the Answers.

As it happens, you're already wrong. We are becoming less and less visible in the radio spectrum, because broadcast technology is extremely wasteful of power. The amount of data carried invisibly over non-broadcast media (like cable TV) is already substantially greater than the amount sent over the air, and most of the major media companies.

Also, the better our encoding and compression technology becomes, the closer our signals become to random noise, which is essentially invisible. In another hundred years, we'll probably look (to today's SETI) just like a a solar flare.....

[scotth]

Originally posted by drkitten

As it happens, you're already wrong. We are becoming less and less visible in the radio spectrum, because broadcast technology is extremely wasteful of power. The amount of data carried invisibly over non-broadcast media (like cable TV) is already substantially greater than the amount sent over the air, and most of the major media companies.


Not really, the stuff that would be most easily detectable are not TV stations. Radars and such would be far easier to detect at a distance.

And even if cable carries more than what is carried over the air, that doesn't mean that what is carried over the air has decreased. It just means the total amount of infomation broadcast has increased.

[shecky]

Originally posted by Marian

Because between SETI and a big mac, SETI wins.

OK, OK. So how 'bout between SETI and a really good pizza?

Mmmm.... Pizza...

[drkitten]

Originally posted by scotth


Not really, the stuff that would be most easily detectable are not TV stations. Radars and such would be far easier to detect at a distance.



No. Radar transmissions are usually relatively low powered compared to media transmissions (since the average area you need to watch via radar is much smaller than the average TV/radio station's footprint).

[scotth]

Originally posted by drkitten


No. Radar transmissions are usually relatively low powered compared to media transmissions (since the average area you need to watch via radar is much smaller than the average TV/radio station's footprint).

I was a radar tech for 8 years and I can tell you categorically.... you are flat wrong on that statement.

The output power of radars are typically MUCH higher than for media transmission, and further they are directional. This would make them detectable at a much greater range with the same output power.

For air search, a low power radar starts at about 100kW. I am not aware of any TV or radio station broadcasting at greater than 100kW.

And there are plenty of 1MW and greater radars. I've worked on a 2.3MW radar. (AN/TPS-32)

[UnTrickaBLe]

OF COURSE it's worth it. it is the most logical and cost-effective search for ET life. If you have any doubts, read some of Carl Sagan's non-fiction flourishes in CONTACT.

[Batman Jr.]

I think people missed my post about why "more complicated" technology may not necessarily make implicit the presence of "less complicated" technology.

Originally posted by Rob Lister

Then again, they might use telepathic communication. I'm not sure what such a discovery might mean for JREF.

If, however, they used nutrino modulation, is it not reasonable that they would have progressed to that technology through others, just as we have progressed through smoke signals to laterns, electrical, CW, AM, FM VHF, microwave and now to fiber?

The problem as I see it is that (even) we have only been visible in the radio spectrum for a hundred or so years. In another hundred or so we will likely again be invisible (assuming we don't remain technologically stagnent.

Perhaps the 'nutrino modulation' comment has more weight than its author knows.

[alfaniner]

Originally posted by Rob Lister


Then again, they might use telepathic communication. I'm not sure what such a discovery might mean for JREF.
...


So, if an alien proves it can communicate telepathically, would it win JREF's Million Dollar Prize?

And what would it do with it?
:p

[Rob Lister]

Originally posted by scotth


Not really, the stuff that would be most easily detectable are not TV stations. Radars and such would be far easier to detect at a distance.

1) What is it you think 'radar' sounds like once you detect it?

2) Why do you think 'radar' will still be in use 100 years from now?


And even if cable carries more than what is carried over the air, that doesn't mean that what is carried over the air has decreased. It just means the total amount of infomation broadcast has increased.

RF pollution has increased, greatly, but it has also become mostly, and intentionally, unintelligible.

[scotth]

Originally posted by Batman Jr.
I think people missed my post about why "more complicated" technology may not necessarily make implicit the presence of "less complicated" technology.



I was trying to point out that RF communication would be expected, more advanced technology musings to the contrary.

Neutrino communications (for example) is pretty much a fantasy idea of SciFi to sound advanced and high tech. Its a pretty rediculous idea, actually. Neutrinos would have to be one of the worst possible choices of things to attempt communications with.

There are 4 forces that can be used to communicate over a distance with. Gravity, EM, strong nuclear, weak nuclear.

EM is the obvious and useful choice. We use it because its properties lend themselves to the task. None of the others do, not even close.

Unless we discover something completely unexpected that would provide for something like "sub-space" communications, ala Star Trek, the EM spectrum is the place to look.

[scotth]

Originally posted by Rob Lister


1) What is it you think 'radar' sounds like once you detect it?

2) Why do you think 'radar' will still be in use 100 years from now?




RF pollution has increased, greatly, but it has also become mostly, and intentionally, unintelligible.

1) Not really a useful way to phrase the question, really... but hopefully this will answer you. If you are just trying to detect (not communicate with) another technological civilization, you just need to detect a clearly artificial radio signal. Radar signals would stand out as artifical very clearly. They wouldn't "sound" like anything though. It will just look like a high power, nearly monochromatic RF source, with very minimal, but clearly artificial encoding. Generally radar signals are encoded just enough to make it clear that you got your own signal back. Therefore they look very deliberately artifical.

2) I can't imagine that we won't be interested in tracking aircraft, spacecraft, weather, or potential incoming missles in the future. We bounce radar off of other planets as well, for that matter, but not on a regular basis.

The signal does not need to be understood or be decoded to realize you have detected an RF signal.

[Rob Lister]

Originally posted by scotth

Unless we discover something completely unexpected that would provide for something like "sub-space" communications, ala Star Trek, the EM spectrum is the place to look.

As has been pointed out by others, you are correct. But you are correct for the wrong reason. We have to look at the EM spectrum because that is currently the only thing we understand well enough. I don't see why that's going to be the case in a hundred years but even if it is, we are already trending to lower power transmission with higher sensitity receivers and completely garbled content.

[Rob Lister]

Originally posted by scotth


1) Not really a useful way to phrase the question, really... but hopefully this will answer you. If you are just trying to detect (not communicate with) another technological civilization, you just need to detect a clearly artificial radio signal. Radar signals would stand out as artifical very clearly. They wouldn't "sound" like anything though. It will just look like a high power, nearly monochromatic RF source, with very minimal, but clearly artificial encoding. Generally radar signals are encoded just enough to make it clear that you got your own signal back. Therefore they look very deliberately artifical.

Okay, what is it you think a radar signal 'looks' like. For example, what does the output of a phased array transmitter 'look' like at a distance of ten or twenty lightyears? A hundred? A thousand?

2) I can't imagine that we won't be interested in tracking aircraft, spacecraft, weather, or potential incoming missles in the future. We bounce radar off of other planets as well, for that matter, but not on a regular basis.

Why do you think that we'll use radar to track such things? Have you no faith?

[/quote]The signal does not need to be understood or be decoded to realize you have detected an RF signal. [/QUOTE]

Why not? Background RF is fairly common.

[scotth]

Originally posted by Rob Lister


Okay, what is it you think a radar signal 'looks' like. For example, what does the output of a phased array transmitter 'look' like at a distance of ten or twenty lightyears? A hundred? A thousand?


Quoting myself.
It will just look like a high power, nearly monochromatic RF source, with very minimal, but clearly artificial encoding. Generally radar signals are encoded just enough to make it clear that you got your own signal back. Therefore they look very deliberately artifical.




Why do you think that we'll use radar to track such things? Have you no faith?

Faith in what? I have faith that radar will improve in the intervening years. The phsyics of the situation dictate much of what the solution is gonna look like.


Why not? Background RF is fairly common.

Background RF is not systematically and intelligently modulated or encoded. You do not need to be able to understand the data, to plainly see that data is being carried on RF.

[Rob Lister]

Originally posted by scotth


Quoting myself.


Faith in what? I have faith that radar will improve in the intervening years. The phsyics of the situation dictate much of what the solution is gonna look like.

So physics, as we understand it today, dictates tomorrow's solution? That's just the part I don't get. That and...


Background RF is not systematically and intelligently modulated or encoded. You do not need to be able to understand the data, to plainly see that data is being carried on RF.

If you think about it, your logic is circular. Still, would you consider the output of a pulsar star to be at least systematic? Would you consider it more or less systematic than the output of a phased array radar?

[scotth]

Originally posted by Rob Lister


As has been pointed out by others, you are correct. But you are correct for the wrong reason. We have to look at the EM spectrum because that is currently the only thing we understand well enough. I don't see why that's going to be the case in a hundred years but even if it is, we are already trending to lower power transmission with higher sensitity receivers and completely garbled content.

I don't think you understand what exactly we (as humans) understand concerning physics, and conversely what we don't yet understand.

There is an implication in your posts, that we are likely to make some fundemental discoveries that would enable entirely new forms of communication at a distance. You are probably thinking about the history of science and the revolutions brought about by Newton, Maxwell, and Einstein during the past. And we must be conceited to think that this won't continue to happen. There is a difference, then and now aren't equivilent.

In the past there were always a stack of observed physical phenomena that we could not adequately explain or explain at all. Today, there are no observations that appear to be outside of explanation with the known forces and particles. What are the problems of today's physics? Getting relativity and QM into one theory.... understanding why there are 4 fundemental forces, why there are 3 spatial dimension, why there are 3 families of fundemental particals?

Resolving any of these outstanding issues wouldn't reasonably lead to some new method of communication that didn't require EM.

[scotth]

Originally posted by Rob Lister

If you think about it, your logic is circular. Still, would you consider the output of a pulsar star to be at least systematic? Would you consider it more or less systematic than the output of a phased array radar?

Really, go study RF theory and modulation. That is what you need to follow this.

A pulsar (other than blinking on and off from the observers point of view, at a regular interval) is not modulated or encoded in any way.

Typical radar signal features:

1) Changing transmit frequency mid pulse
2) Typically phase modulated
3) Very narrow band

The 3rd feature isn't especially useful, but the first two would make it look very artificial.

Putting data on a carrier is called modulation. Even with no idea what the data is, or how it is encoded, communication and radar signals look "made".

[drkitten]

Originally posted by scotth


There are 4 forces that can be used to communicate over a distance with. Gravity, EM, strong nuclear, weak nuclear.

EM is the obvious and useful choice. We use it because its properties lend themselves to the task. None of the others do, not even close.



Why do you assume that we need to use forces to communicate at a distance? I communicate with particles --- well, they're usually called "pieces of paper" --- all the time. Similarly, much of my communication is done with much smaller particles called "electrons." I don't see any particular reason that I can use electrons for communications and not (assuming sufficiently advanced technology) mesons, neutrinos, yadda yadda.

More to the point --- communicating via EM specifically does not imply that the EM is detectable as a communication at a distance. For example, I can use a laser (which is, of course, an EM signal) to communicate between two points without having anyone else pick up the beam outside of the direct line-of-sight, since a laser beam is directional. As another example, since the bandwidth of any channel is limited, I will probably want to compress data before I send it --- a really good compression system will yield data that's indistinguishable from noise.

Our hypothetical aliens may be communicating using a directional, highly compressed signal carried by a stream of high-speed mesons. SETI would never find that.

[scotth]

Originally posted by drkitten


Why do you assume that we need to use forces to communicate at a distance? I communicate with particles --- well, they're usually called "pieces of paper" --- all the time. Similarly, much of my communication is done with much smaller particles called "electrons." I don't see any particular reason that I can use electrons for communications and not (assuming sufficiently advanced technology) mesons, neutrinos, yadda yadda.

More to the point --- communicating via EM specifically does not imply that the EM is detectable as a communication at a distance. For example, I can use a laser (which is, of course, an EM signal) to communicate between two points without having anyone else pick up the beam outside of the direct line-of-sight, since a laser beam is directional. As another example, since the bandwidth of any channel is limited, I will probably want to compress data before I send it --- a really good compression system will yield data that's indistinguishable from noise.

Our hypothetical aliens may be communicating using a directional, highly compressed signal carried by a stream of high-speed mesons. SETI would never find that.

Communicating with particles in this context is a difficult, hazardous, and generally stillborn idea. Sufficiently advanced technology would not make them a good choice.

While it is interesting to think about closed beam (laser in your example) communications, it would never be used for broadcast communications and certainly not for radar. The whole point of radar is to search for things you don't know are there. And therefore largely transmitting at nothing at all.

And radar signal will never be encoded like you suggest. Putting alot of modulation on a signal spreads its spectrum and greatly reduces the range at which it can be detected. That is why a radar signal will always be only modulated just enough to make it easy to recognize in the background noise.

You are coming up with classes of communication that would not be useful to look for, but the existance of these would not in any way preclude the existance of more easily detectable RF.

[Batman Jr.]

Lasers do have the advantage of being able to carry more information than radio waves. As far as the problem of their narrow broadcasting field, couldn't an array of lasers reconcile this predicament?

Originally posted by scotth

You are coming up with classes of communication that would not be useful to look for, but the existance of these would not in any way preclude the existance of more easily detectable RF.

You didn't read my post yet, did you? A mind sufficiently disparate from a human's may come up with certain methods of communication before RF. If such a method is superior in the opinion of the alien to RF, then it may very well preclude RF. What you fail to grasp is that concepts of complexity and simplicity and pragmatism are all relative.

[scotth]

Originally posted by Batman Jr.
You didn't read my post yet, did you? A mind sufficiently disparate from a human's may come up with certain methods of communication before RF. If such a method is superior in the opinion of the alien to RF, then it may very well preclude RF. What you fail to grasp is that concepts of complexity and simplicity and pragmatism are all relative.

I did, and I thought some of what I put in there rebutted it... but here it is specifically.

When you are guessing about communicating with or even detecting another civilization, you have to consider what you know in common. Another technical civilization would have figured out the same things about the universe that we have in order to achieve technology.

Where your arguement goes off course is that it posits that there is some reasonable way of sending data without wires that uses something besides the EM spectrum. As far as we can tell today, nature simply doesn't provide another useful tool for the job.

Like I said before, every thing that we can see going on in the universe is neatly covered by 4 forces and a small stack of particles. Particles are not useful for communications. That leaves the forces, and only one of them is useful, and that is electromagnetism.

It doesn't matter how differently they think, or how different their culture may be, or whether would could ever even understand them. If you want to send signals without wires, EM radiation is the way to do it.

[Batman Jr.]

EM can be manipulated in a multitude of ways each to different effects. Lasers and radio waves are both EM, but require different apparatuses in utilizing them as mediums for communication. You assume that I'm excluding EM entirely, which I'm not.

Originally posted by scotth

When you are guessing about communicating with or even detecting another civilization, you have to consider what you know in common. Another technical civilization would have figured out the same things about the universe that we have in order to achieve technology.

You still haven't told me how you know this. Consider a composer and a less musically inclined computer scientist attempting to train a computer to compose for him based on certain mathematical algorithms. The composer's thought processes in creating a piece of music are mostly subconscious, almost as if he were merely taking dictation for a symphony which resided in his mind's ear. The computer scientist, however, must completely reverse engineer music down to its most fundamental terms in teaching the computer what the composer takes for granted. In this scenario, the composer is required to know less than the computer scientist despite the fact that they have the common aim of just getting a new piece of music written! By your logic (if you assumed yourself to be the computer scientist), Erich—he's the man with the bowtie on your left—ought to have understood the exact mathematics governing music. Otherwise, it would have been impossible for him to have written Die Tote Stadt, the film score to The Sea Hawk, etc.

[scotth]

Originally posted by Batman Jr.
EM can be manipulated in a multitude of ways each to different effects. Lasers and radio waves are both EM, but require different apparatuses in utilizing them as mediums for communication. You assume that I'm excluding EM entirely, which I'm not.



You still haven't told me how you know this. Consider a composer and a less musically inclined computer scientist attempting to train a computer to compose for him based on certain mathematical algorithms. The composer's thought processes in creating a piece of music are mostly subconscious, almost as if he were merely taking dictation for a symphony which resided in his mind's ear. The computer scientist, however, must completely reverse engineer music down to its most fundamental terms in teaching the computer what the composer takes for granted. In this scenario, the composer is required to know less than the computer scientist despite the fact that they have the common aim of just getting a new piece of music written! By your logic (if you assumed yourself to be the computer scientist), Erich—he's the man with the bowtie on your left—ought to have understood the exact mathematics governing music. Otherwise, it would have been impossible for him to have written Die Tote Stadt, the film score to The Sea Hawk, etc.

EM is EM. That is the situation.

To put data on it, it must be varied in some way.

You can turn it on and off.
You vary the amplitude.
You can vary the frequency.
And you can shift its phase.

That is it. Its that simple.

If you detect EM radiation that is changing in one or more of the above aspects in such a way that it could not be caused by nature, you probably have a signal created by another intelligence.

Your analogy to creating music doesn't illuminate the situation at all.

[Thomas]

Scotth,

If you think EM is the best solution for interstellar communication, I would have to say that you're quite wrong. Quantum communication, based on the 'spooky action-at-a-distance' as Einstein called it, is far the best solution we know of today. EM is a joke compared to quantum communication:

Seth Shostak from the SETI institute says:

Could quantum messaging dominate interstellar communication? Could this be the preferred way to get in touch with unknown cosmic beings? If so, it offers an appealing resolution of the famous Fermi Paradox, which asks "if the Galaxy is teeming with intelligence, why don’t we see evidence for it everywhere?" Perhaps the evidence is everywhere – washing over us right now in a shower of quantum-encrypted messages.


It is most likely that this is the way aliens would try to communicate with us, there is nothing that can interfere with these signals, and they happen instantly, no travel needed, spooky action-at-a-distance.
Even the most powerful transmitters we use today, can only be detected 50 lightyears away, and the odds for being 'heard' within this range, is minimal. Actually it would require an antenna to be 1,000 feet in diameter. With perfected quantum communication systems, distance becomes irrelevant.

I think that if there is someone out there, we're gonna find out when we have perfected quantum communication.

Source for the quote (http://www.space.com/searchforlife/shostak_quantum_030522.html)

[Thomas]

By the way, I voted yes, although I belive they are looking for the wrong signals as I said in my previous post. But I like the philosophy behind SETI, and quantum communication is belived to be in our hands within the next 10-15 years. I indeed think it's worth the try.

[Batman Jr.]

Originally posted by scotth

Your analogy to creating music doesn't illuminate the situation at all.

In my analogy, the computer scientist has certain prerequisites for creating music and the composer has others. Your statements allude to your thinking that everyone must have the same prerequisites in achieving the same things. I was attempting to provide a specific and tangible counterexample to this notion.

The point I was trying to make to begin with is that there is no set linear path that technology always follows.

There is an optical SETI program that succors the radio wave one, so that's good. In contrasting lasers and radio waves, I had meant to specify that I wasn't talking about lasers in the radio spectrum. I apologize as that got a little convoluted.

However, I cannot so readily dismiss the possibility of more unconventional forms of deep space communication.

[Thomas]

Originally posted by Batman Jr.
There is an optical SETI program that succors the radio wave one, so that's good. In contrasting lasers and radio waves, I had meant to specify that I wasn't talking about lasers in the radio spectrum. I apologize as that got a little convoluted.
What's the point? They wouldn't be sending anything with such primitive signals anyway. It's like if I tried to send you this message in a bottle through the Atlantic ocean. And that's even a poor analogy, because both the internet and the message-in-a-bottle takes time, quantum signals don't.

[Rob Lister]

Originally posted by Thomas

What's the point? They wouldn't be sending anything with such primitive signals anyway. It's like if I tried to send you this message in a bottle through the Atlantic ocean. And that's even a poor analogy, because both the internet and the message-in-a-bottle takes time, quantum signals don't.

The problem with 'quantum signals', at least as you describe them, is that they cannot be used to convey intellegence at speeds greater than c; doing so would violate causality.

edit: clarification. Also to add: But their great for encryption.

[Thomas]

Originally posted by Rob Lister
The problem with 'quantum signals', at least as you describe them, is that they cannot be used to convey intellegence at speeds greater than c; doing so would violate causality.
They do violate causality. That's what quantum mechanics do. Determinists like Einstein claimed to the day he died that the QM theory would have to be flawed, and there are still objections to this day. I don't understand QM, actually noone really does because it conflicts with common sense, but it works anyway. That's the ugly part about it. Experiments have been made where particles have been, hold on, teleported.

And other experiments have been conducted where quantum communication have been verified over small distances. But in theory it doesn't matter if the distance is 1000 lightyears, or 2 feet. One particle knows what the other one is doing, it's quite weird, but it works. Or put in another way, if you look at one particle, you'll know the state of the other particle.

[scotth]

Originally posted by Thomas
Scotth,

If you think EM is the best solution for interstellar communication, I would have to say that you're quite wrong. Quantum communication, based on the 'spooky action-at-a-distance' as Einstein called it, is far the best solution we know of today. EM is a joke compared to quantum communication:


Just what is in this, indicates you don't understand this at all.

This would still be EM communications. What they are actually discussin is quantum encoding of photons (EM).

And it changes not one thing about my arguments about detecting things like broadcast or radar leakage.

[scotth]

Originally posted by Thomas

They do violate causality. That's what quantum mechanics do.


No, they don't. Period.

[Thomas]

Originally posted by scotth


No, they don't. Period.

Excellent argument, but Here (http://fergusmurray.members.beeb.net/Causality.html)

[scotth]

Further problem with quantum communications scheme.....

The sender would have to hit the recipients position exactly for the message to be found. When I say exactly, I mean very exactly. The receiving system would have to be place at exactly the intersection of where the quantumly entangled photons are to meet.

[Thomas]

Originally posted by scotth


Just what is in this, indicates you don't understand this at all.

This would still be EM communications. What they are actually discussin is quantum encoding of photons (EM).

And it changes not one thing about my arguments about detecting things like broadcast or radar leakage.

From the same source as above:


These two scientists have been researching quantum information theory for a while. Their trick is to forego conventional electromagnetic signals (light or radio) – made up of large, organized "waves" of photons – in favor of individual, quantum-entangled photons.


If I have misunderstood something here, then you are welcome to explain, but I gotta go for now. Stay cosy.

[scotth]

Originally posted by Thomas


Excellent argument, but Here (http://fergusmurray.members.beeb.net/Causality.html)

This is a pretty out of date article.

It has been demonstrated quite well that it is impossible to use any of these tricks to pass information at greater than the speed of light.

I'll see if I can dig up an article on that.

[scotth]

Originally posted by Thomas


From the same source as above:



If I have misunderstood something here, then you are welcome to explain, but I gotta go for now. Stay cosy.

Quantumly entangle photons are still photons. Photons are EM. Photon are the particle the mediates the Electromagnetic force.

[Thomas]

I see now that you're right, quantum entanglement would only be used for encryption in this case, an illusion deprived again.

But Shostak could have a point, that this could be the preferred method for another civilization to communicate, with quantum-cryptation, and we therefore can't 'hear' anything yet.

But you know, not to be a nag, but QM do break causality/determinism. Atleast that's how the picture looks now. Spooky action-at-a-distance breaks causality. That's what I been seduced to belive anyway, although I think it sounds rather akward.

[Rob Lister]

Originally posted by Thomas
Spooky action-at-a-distance breaks causality.

No, it doesn't, at least not until you can use it to convey intellegence at speeds greater than c, which you can't, because that would violate causality. Talk about circular!!! But in this case it's necessary.

[Thomas]

Goddammit, I thought they were talking about talking entanglement into another level, and manipulate the state of each of single particles at any distance without really having them entangled to begin with. I saw perspectives for while, that could have been so effective for long distance communication. And many other things.

[Thomas]

Originally posted by Rob Lister


No, it doesn't, at least not until you can use it to convey intellegence at speeds greater than c, which you can't, because that would violate causality. Talk about circular!!! But in this case it's necessary.

http://focus.aps.org/story/v10/st29

Well, it does, and that's why Einstein didn't like QM. Relativity and QM contradict eachother.


If a pair of fundamental particles is entangled, measuring an attribute of one particle, such as spin, can affect the second particle, no matter how far away.

[scotth]

Originally posted by Thomas


http://focus.aps.org/story/v10/st29

Well, it does, and that's why Einstein didn't like QM. Relativity and QM contradict eachother.

I don't see where that article indicates that information is being passed at greater than light speed.

Edited to add... and so far Relativity and QM do not contradict each other. Relativity does have the problem of breaking down at arbitrarily short distances (String theory potentially resolves this by adding a "granularity" to space, if you will). None the less, no QM phenemena has been observed which actually violates Relativity.

[Thomas]

Originally posted by scotth


I don't see where that article indicates that information is being passed at greater than light speed.

here,


If a pair of fundamental particles is entangled, measuring an attribute of one particle, such as spin, can affect the second particle, no matter how far away.


There are 'communication' between them at any distance, instantly.

[scotth]

Originally posted by Thomas


here,



You would then have to be able to demonstrate that information can actually be passed. It does give the illusion that it may be possible, however, that has been demonstrated to be false.

[Thomas]

Originally posted by scotth


You would then have to be able to demonstrate that information can actually be passed. It does give the illusion that it may be possible, however, that has been demonstrated to be false.
Let me rephrase it then, quantum mechanics are considered a non-deterministic theory (acausal), and relativity is a deterministic theory (causal).

If you have any arguments against that quantum mechanics should break with determinism, I would like to hear them, because I don't really like that it does. Nor did Einstein.

[Thomas]

Originally posted by scotth
You would then have to be able to demonstrate that information can actually be passed. It does give the illusion that it may be possible, however, that has been demonstrated to be false.
Yea, I've heard that, but on the other hand, as I have understood it, nobody knows what actually happens either, is that same you've heard? Anyway, this time I have to run, see you later perhaps.

[CurtC]

Nobody knows what actually happens? That's pretty much true with any aspect of QM. However, we are able to mathematically predict the effects with an extremely high degree of precision. Quantum entanglement wasn't an experimental result that was discovered by accident - the theory predicted it, and the result was verified. In that sense, we understand what happens really really well, and you can't use that to communicate information at greater than c.

Do the particles communicate with each other at a speed greater than c? Well, maybe. The theory says that the state of the remote one is instantly determined, which sounds pretty much like that to me. But this can't be used to send information.

Even the most powerful transmitters we use today, can only be detected 50 lightyears away, and the odds for being 'heard' within this range, is minimal. Actually it would require an antenna to be 1,000 feet in diameter. With perfected quantum communication systems, distance becomes irrelevant.This is not true at all. Signal power drop-off is a result of shotgunning waves (photons) out in a broad spread, and when they get 50 light years out, there's not enough of them left to distinguish the signal from noise. This is also known as the inverse square law. But with your quantum communication, the photons would have to be rifle-shot exactly to their intended destination. This is just another aspect of the same problem.

[drkitten]

Originally posted by scotth


You would then have to be able to demonstrate that information can actually be passed. It does give the illusion that it may be possible, however, that has been demonstrated to be false.

I love your confidence that the physics of the early 21st century has solved all the issues in physics apparent to our hypothetical space aliens. Especially the issues that are currently the subject of high-level debate in our own journals. Your statement that information cannot be passed via quantum entanglement, for example, is not supported by the various national research foundations, or they wouldn't have funded experiments in this area.

Are you claiming to know this area better than the NSF? I can put you in touch with Dr. Dehmer if you like.

[scotth]

Originally posted by drkitten


I love your confidence that the physics of the early 21st century has solved all the issues in physics apparent to our hypothetical space aliens. Especially the issues that are currently the subject of high-level debate in our own journals. Your statement that information cannot be passed via quantum entanglement, for example, is not supported by the various national research foundations, or they wouldn't have funded experiments in this area.

Are you claiming to know this area better than the NSF? I can put you in touch with Dr. Dehmer if you like.

I meant to say, passed at greater than the speed of light.

[drkitten]

Originally posted by scotth


I meant to say, passed at greater than the speed of light.

Yes. And your central assumption is that, as this would "violate causality," it must be impossible.

The NSF and similar funding agencies (in particular ONR) are willing to investigate the possibility of global causality violation. Such theories have been proposed (by Bohm and others) as early as 1951 and are still active research areas today.

What do you know that the head of the NSF Physics Division doesn't? Why is he willing accept non-localist interpretations of QM as potentially valid, while you are not?

[scotth]

Originally posted by drkitten


Yes. And your central assumption is that, as this would "violate causality," it must be impossible.

The NSF and similar funding agencies (in particular ONR) are willing to investigate the possibility of global causality violation. Such theories have been proposed (by Bohm and others) as early as 1951 and are still active research areas today.

What do you know that the head of the NSF Physics Division doesn't? Why is he willing accept non-localist interpretations of QM as potentially valid, while you are not?

Don't confuse what I said with CurtC's post.

I said that FTL communication has been recently investigated and shown not to be possible. I also indicated that I would try to find some articles on that.

I'll also add, that I remember that it was shown in theory why it would not actually work, and that experiment actually agreed with that quite nicely.

[drkitten]

Originally posted by scotth


Don't confuse what I said with CurtC's post.

I said that FTL communication has been recently investigated and shown not to be possible. I also indicated that I would try to find some articles on that.

Yes, and I said that the NSF and ONR consider the jury to still be out on whether or not it's possible.

What do you know that the NSF doesn't?

I remind you of Clarke's Laws : "When a distinguished but elderly scientist says something is impossible, he is very probably wrong."

[scotth]

Originally posted by drkitten


Yes, and I said that the NSF and ONR consider the jury to still be out on whether or not it's possible.

What do you know that the NSF doesn't?

I remind you of Clarke's Laws : "When a distinguished but elderly scientist says something is impossible, he is very probably wrong."

Have any links to where the NSF and ONR are still discussing FTL communications?

I'd be interested in reading it.

[drkitten]

Originally posted by scotth


Have any links to where the NSF and ONR are still discussing FTL communications?

I'd be interested in reading it.

Check out the recent NSF/ITR proposals, especially the physics-heavy ones, and see if any of them satisfy you.

More directly, I refer you to the paper "Superluminal solutions to the Klein-Gordon equation and a causality problem," (Phys. Lett. A.) by Borghardt et al. (although they're operating out of the Ukraine, and so don't have US-based funding), where they're explicity investigating the possibility of causality violations. There's similarly a large body of extremely recent (2003-4) work investigating the apparent superluminality of quantum tunnelling.

None of the researchers have yet found a clear-cut case of superluminal information transfer, but they all clearly regard the question of causality violation as an open one.

[heath]

back onto topic...

I'm a supporter of SETI and think the idea is good in principal but I've always had reservations about the methodology in relation to the very narrow band of radio wavelengths they monitor.

I agree some assumtions need to be made to narrow the field from the effectively infitinite EM spectrum to something manageable with modern technology but I've always found the justification for the range chosen a bit to "airy fairly" for my liking.

I'm looking for a link to the bands monitored and the justificiation for it to make sure my feeble mind isn't deceiving me again...

Here's one with a nice graph (http://computer.howstuffworks.com/seti1.htm)

[Dancing David]

Originally posted by Rob Lister



Perhaps the 'nutrino modulation' comment has more weight than its author knows.

Very little mass, my point is that it is about detecting other possible lifeforms with what we have, there are good reasons that radio waves will continue in use for a long while. mainly the transparency of the universe.

[Dancing David]

Originally posted by drkitten


There's similarly a large body of extremely recent (2003-4) work investigating the apparent superluminality of quantum tunnelling.


I think someone told me that these properties could not be used for data transefer.

[drkitten]

Originally posted by Dancing David


I think someone told me that these properties could not be used for data transefer.

Yes. And I'd love to know how that person who told you knew that that was the case, when the researchers are still doing the experiments and investigating the questions.

I repeat : what does he know that the scientists currently working in the area don't? How does he know the results of the experiments before they are performed?

[Dancing David]

I believe that it was Zombiefied, and his point was that the superluminal properties are essentialy a random component of the 'sum of histories', and so while superluminal properties exist and are somewhat established they are an effect of the standard theory and not a new expansion of the theory.

I am not saying that current reasearch is not ongoing, just that this was a response to comment I had made.

The main issue I have with some of the superliminal research is that we cant really do the experiments over a distance that really demonstrates anything other than a local phenomena.

(Sorry, I have probably made a msih mosh of the whole thing and totaly misrepresented what I was told, I was pointing out that the speed of light is not actualy a constant, it is an average over the history of the photon. This apparently was not sufficient to allow for data transmission faster than the speed of light. I was making reference to the Italian studies where a photon arrived at the receptor in a frame of reference 'earlier' than the standard theory would predict.)

[thaiboxerken]

Nope, there are better places to send the resources that are wasted on SETI. While we're at it, we should stop spending money on homeopathy and psychic nonsense too.

[SquishyDave]

I think SETI's well worth it, sure more advanced aliens, or even less advanced aliens might not use EM, but what if there is more than one intelligent set of ET's, and just one other out there like to use EM. We are so late on the cosmic scene that IF there is other intelligent life, then we might just pick up on it.

But as discussed, even if SETI finds nothing, it might just help refine some technology somewhere.

And even if we get nothing out of it ever, I feel it is worth it. Humans make works of art, we write poetry, we make music, for no reason other than that we find them pretty, we imagine impossible worlds where dragons cast spells and elves shoot arrows, and we point EM collectors at the sky and listen, hoping..........