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Should SETI Be Looking For Lasers Instead?
colonist writes "Frank Drake, creator of SETI's famous equation, says the detection of extraterrestrial radio signals won't work, because Earth's own radio signal will only be around for 100 years. More and more of Earth's communications use cable and satellites, with no radio-frequency leakage to space. Instead, we should be looking for intentional signals in the form of high-powered lasers that could 'outshine the sun by a factor of 10,000'. Meanwhile, Paul Davies writes that we should be conducting SETI in our DNA. In turns out that an alien message designed to last millenia should be 'inside a large number of self-replicating, self-repairing microscopic machines programmed to multiply and adapt to changing conditions', otherwise known as living cells. Are we the message?"
Optical (ie: laser detection) SETI has been up and running for a while now (see Optical SETI overview for example). Drake ought to declare an interest though, since he's one of the investigators on the project.
It's a reasonable argument, but it's far harder to set up optical "listening" posts than radio ones. It cost me about 1000 uk pounds (WHY is the pound symbol banned from
The counter argument of course is that to detect laser light, the remote civilisation have to be pointing their laser at us, whereas with radio it doesn't matter since it's not a directed beam. Against that you have to offset the time-period over which transmissions of either kind could be made...
The chances of getting a radio contact may be a few orders of magnitude lower than getting an optical contact, but since the chances of me setting up an optical SETI station are precisely 0, the chances of getting 'the' signal with radio is infinitely greater than with optics, at least for me
Simon
Physicists get Hadrons!
The message only contained two words:
FIRST POST!
Are we the message?
I guess that's akin to leaving a flaming bag of poo on the doorstep.
"We apologise for the inconveniance."
Is a message allowed to read itself?
Maybe we should consider the possibility that we are part of a device to perform some calculation to find the answer to a certain big question.
Then we hardly need a whole lot of computers to see them!
yup. And the message is 41,99999999 (ad finitum)
When will I end this grieving ? When will my future begin ?
We dump pretty enormous amounts of energy at RADAR wavelengths, 24/7, across the night sky. That'll stop approximately when we have no fear of hostile aircraft showing up at our borders.
You know, never.
--Dan
And exactly since when do satellite uplink transmissions stop at the satellite? The uplink is a radio wave, albeit a directed one. It might still be possible to pick up an alien uplink signal.
viruses and non-eukaryotes have to be too efficient with their DNA. Anything not needed will get discarded
___
It's the end of my comment as I know it and I feel fine.
Oh sure, yeah, right. DNA is the frickin' solution to everything, isn't it?
... sheesh.
Next thing you know, all those conspiracy nutters who say we are "Children of the Gods" will be being appointed to national agencies
Look, if someone knows something about space aliens, then OUT WITH IT!! Why the American people have put up with Area 51 for so long without any sort of culpability being required of their government, I do not know. Of the people and for the people, my ass.
Of the Grey Overlords, and For the Grey Overlords. Lets just call it a spade.
; -- the corruption of government starts with its secrets. a truly free people keep no secrets. --
seti in dna article : bugmetnot is your friend
I for one welcome our DNA-speaking, laser-shooting overlords. :-D
"When all you have is a hammer, everything starts to look like a nail"
Next thing you know, we will look for SETI in the burn pattern of a tortilla...or maybe in the reflection from a store window...
Is anyone getting my point here?
"For centuries, mankind has searched for evidence of God, in the skies, in the stars, in animals and in himself." Now do a search and replace s/God/aliens/ and ask if this is really any more a sensible statement. Not to mention, if we do find aliens, are we their peers, or are they our gods?
Final thought of the day...from what I can understand, our solar system is rather young compared to other galaxies out there. And apparently there are hundreds of planets capable of supporting life (our life, that's not even counting life that forms in some environment we consider hostile). Well if that's the case, and life/evolution is as easy as the theories make it sound (all it takes is heat and time)...then why isn't the universe like something out of Star TRek with hundreds of alien species flittering about, dropping in to violate the prime directive, establish moonbases, and so forth? Think about it.
- JoeShmoe
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-- I wonder which will go down in history as the bigger failure: the War on Drugs or the War on Filesharing
Aliens with frickin' laser beams on their heads?
Because that would rock.
Remember, it takes 42 muscles to frown and only 4 to pull the trigger of a sniper rifle.
is in our mitochondria.
That is to fool the lameness filter. It counts the capitals or something like this.
We don't need to search there.
Quoted from the article: The cargo would be designed to infect, without harm, any DNA-based life it encountered.
There, they KNOW that we are a DNA-based life form, universally sprung from a watery solution, the salty sea. Like we all know, that harmless DNA can be engineered quite easily. That's why I don't understand that all the rocks from the moon (and mars) are in quarantine
I think we would probably be able to program organisms from scratch by that point, so what kind of organisms would you send to establish life on a distant planet? It would probably start off small, or virus like, but would need to be preprogrammed to evolve into something more complex. Since the evolution would be random, you really couldn't determine the outcome after billions of years.
Then it occurred to me that if we were going to go through all this trouble for a slight chance that these packets of life might just thrive and grow some brains, we would probably put some kind message in there. Then it occurred to me that we could possibly be the product of such a plan.
It is possible that the structure of the genetic code itself is an artificial creation of an advanced race. Maybe we should examine the fossil record to look for patterns in the earliest life on the planet. Maybe humans got an evolutionary speed pass to intelligence. Who knows? At any rate understanding the underlying structure of genetic programming would be necessary for understanding the rational behind choosing one structure over another. Just like programmers develop an understanding of the language they program in, perhaps we'll see some calculated order to it all.
If one such laser beam would hit the earth, I don't think it would be a message like 'hi there, we are cute nice aliens from outher space and we are going to give you world peace!'. NO this alien death ray would mean something like 'Sheez, what a bunch of morons you puny earth dwellers are. Die die die!!1'. I would not bother building a giant listening post for that message. :/
You know it makes sense, a little reminder from jointm1k.
Sorry buddy. There are a couple of dozen, possibly even hundreds of stars within 25 light years. Alpha Centuari is something like 4.1 lightyears away. So, sun excepted, it takes a hair over 4 years for light from the nearest star to reach us.
Second. What does the difficulty of getting to Saturn have to do with making sense of radio signals?
Erm, are you SURE about that?
Ignoring the real nearest star, Sol, the next nearest star is Proxima Centauri which is 4.22 light-years away... i.e. its light only takes 4.22 years to get here, not the 25 you claim.
There are 25 known stars within 13 lightyears. Their light won't take 25 years to get to us either.
Seriously. You wanna check your random information before presenting it as a fact!
People should not be afraid of their governments - Governments should be afraid of their people.
viruses and non-eukaryotes have to be too efficient with their DNA. Anything not needed will get discarded
I disagree.
To quote the above linked source
"In reassortment, two separate viral strains, sometimes from different host species, infect the same cell and swap whole segments of one or two genes. This is how the 1957 and 1968 strains may have originated. The 1957 strain, which killed 70,000 in the United States, carries three gene segments from ducks and five from humans. The later version, which took a U.S. toll of 34,000, mixes two duck segments with six human ones."
Human and Duck DNA in one strain of the Flu virus doesn't sound very efficient to me.
LK
"Hi. This is my friend, Jack Shit, and you don't know him." - Lord Kano
I found the message! Encoded in my own DNA! It says you should each send $50 to:
PO Box 1922
Anchron, OH
30544
Swear to god. Obey the aliens.
Beware blue cats moving at
In ST:TNG, of course! This episode
I think we're really looking in all the wrong places. We're putting human assumptions on alien life.
We assume they would be using radio communication, or that they'd bother with a high-power laser. What if their communication is completely different. Like, something we haven't even considered to be a possibility yet, even in SciFi.. In a transmission media we don't even realize, we may be receiving communications from them, but we simply don't have the equipment to hear it.. We can't even decipher what any other creature on this planet is trying to communicate, why should we even be so egotistical to thing that not only would we know how to receive their communication, but have the vaugest idea of what they're saying.
I thought the idea of SETI was that we'd pick up an omni-directional broadcast, with some alien saying "here we are, can anyone hear me" A laser would be directional. It would have to be intended for Earth, and would need to be tracking many years ahead of where we are. We aren't broadcasting the same signal, why would they? There could be many planets near by with the same idea of listening, but if no one's talking, there's no communcation.
Maybe pulsars aren't just some celestial event, maybe they're beacons, and when we're ready to go to them, we'll find more information. But for now (and the next hundred+ years), we won't be going anywhere near them. Like, we haven't even managed to get a person to the next planet yet. There isn't enough "push" to develop to the next level. Imagine if every country spent their military budget on developing space travel. we'd alerady have a flag on Pluto, along with a bunch of empty beer cans from tourists.
But no, we waste our resources blowing each other up, or making sure we're on the virge of it every day. Remember the cold war? Ya, 40 years of "I'm going to kill you all", just for it to fall apart, and both sides realize that those people we were so scared of for so long aren't really that bad.
I grew up knowing the Soviet Union was the evil Red Army, who had so many weapons pointed at us because they hate us so much. Now, thanks to the fall of the Soviet Union, and the rise of the Internet, I now frequently talk to a Russian, and really, he's a nice guy. I've seen some beautiful pictures around where he lives, where not too long ago I would have believed was a frozen wasteland.
If only all of our governments would give up on this nonsense and cooperate in things, or better yet, ditch the whole "This is ours, you can't play with it" mentality, we'd make a lot more progress.
[rant mode off]
Serious? Seriousness is well above my pay grade.
The divergence of a laser beam is, assuming ideal optical components, mostly dependent on the diameter of the beam where it starts. You can take a big telescope and let the light pass through in the opposite direction, so let's say, a diameter of 4 meters. For visible light, that will generate a beam with a divergence of 1e-14 sr. So, to get to 2e29 W/sr, you need a laser with a power of no less than 2e15 watts. (Compare this to a mid-size electrical power plant at 1e9 watt...)
Yes, there exist lasers that can generate ultrashort pulses in the near-infrared, with such a high peak energy, say 100 femtoseconds (100 fs=1e-13 s) and 100 joules per pulse, so there you have our desired fluence.
Unfortunately, such lasers can only fire something like one shot per second. If you really want to appreciate the high peak power, you need a camera with a shutter time of 100 fs. Imagine looking at the sky with such an ultrafast camera. The chance that you actually manage to catch a flash from this laser is virtually zero, unless you have a way to know when the flash is going to come. Someone who is looking at a nearby star and expecting flashes is more likely to have an aperture time of 0,1 seconds or so in order to capture any photons at all. At 0,1 seconds aperture time, the laser is no longer 10,000 times more bright than the nearby star (that is, our sun), but rather 1e8 times weaker.
So, it is unlikely that this is going to word, assuming that someone is looking at us anyway.
Avantslash: low-bandwidth mobile slashdot.
As for the other gasses we don't know here - we know all the elements that exist and many that don't exist (ones that we created in labs but don't exist in nature) so we have a pretty solid idea of what possible gasses there are out there. Oxygen breathing, carbon based, water dependent life is possible since we've seen it (us). Carbon and water have special and unique properties that make them ideal for creating life as we know it. If we start looking for "whatever" how will we know we've found it?
this genetic sequence is licensed under GLP...
The question "Are we alone?" is one of the most important philosophical questions; keep in mind that what we call "science" today was once called "pysical science". Philosophy was the profession of scientists centuries ago, and should be part of the toolkit of scientists today.
From a observational standpoint, you have the (yet unproven) theory: There is life outside Earth. In order to try to prove this theory (disproving it is much harder =), you gather data and analyze it. That's generally considered part of science. If for example, Mars missions finds self-replicating life, that can provide an answer to the simpler proposition. The harder one -- intelligent life -- would still need to be shown in some other manner. (Unless we found self-replicating intelligent life on Mars, of course.)
As for the "who cares, I'll be dead by then!" narrow-focused people, keep in mind that the tools and networks being developed for SETI -- massively parallel data set computations -- have usages for other areas of "science" that you would probably consider to be science -- protein folding, for example.
With the promise of quantum communication, it is conceivable that (if Quantum communication is indeed feasible) we should be focussing our optical light search on specific photons of light.
Anyone know about beam splitting entangled pairs etc. Many moons ago, Einstein, Podolski, and Rosen carried out there unusual experiment whereby the they observed what is now known as quantun weirdness. A photon in an entangled state could be split using a sophisticated 50:50 beam splitter. Each split photon could travel off in opposite directions and appear to be twins, in the sense that any change in behaviour of one would instantly (exactly synchronized regardless of distance!!!) be felt by the other, its twin.
Evidence that this was no fluke is gathering thanks to continuing experiments, yet it is still not in stone.
My reasoning is that if this phenomenan is genuine, it could be one way extraterrestrials would chose to contact us. Why not. They send a conventional optical signal, only this time encased in a surrounding cylindar of light, thus allowing for the entangled photons charateristic properties to be influenced only by this cylinder of light. Allot can till go wrong so conceivably, the 'ET's' would send a large stream of such light cylinders- the centre of which is a stream of entangled photons. That way any measurement of the entangled photon would cause an immediate change to its twin (The twin photon - of entangled pair)would presumably be archived on the alien world bouncing back and forth in a cavity (not unlike the cavities we use today - only presumably far more advanced.) So, once change is observed, an immeditae alarm bell is triggered. The ET's can know instantly someone/something has comeinto contact with their signal. Just like Earth SETI, the ET SETI would categorise all their findings and have mant false positives. They would probably already have chartered the area of space to which they send a signal. They may know the only objects (meteorites, stars, planets, commets...) that are likely influences over the transmitted light signal. Hence, if we Earthlings intercept the light in a very manufactured manner (i.e fire a encoded light signal of our own into theres, they are likely to get some unusual data back at there end - instantly.
Anyway, lets face you can't have an interest in SETI without being imaginative.
All Im tring to say is.
1) If I were a highly advanced ET, I would use Quantum entaglement (if it is indeed feasible) to transmit photons of light.
2)I believe we should start sending entangled photons of light, encased in our own manufactured cylinders of background light, out into space.
3)I hope SETI read this.
Maybe someone can enlighten me, because I never understood why SETI got much effort at all. Any random signal we could eavesdrop on seems like it would likely becoming from a planet like ours, transmitter on a surface that is moving around an axis that is moving around a sun that is moving around a galaxy. Radio waves might cut a fair (if increasingly faint) arc into the Universe under such conditions, but a laser? Wouldn't that make it a pressing assumption that aliens knew we were here? And I don't mean just "here here" but "there here": contact in a manner that accounted for our movements over the time scales it would take for a directed signal to reach the planet. I mean, pick any random star of billions in the night sky and assume a planet around it had intelligent life on it. Now where exactly would you point your beacon so that it actually hit that target? And why is it we think we're on the receiving end of such improbable attention?
Are we the message?
m
m
That's exactly the idea from The Outer Limits : Double Helix, and sequel, The Origin Of Species.
http://theouterlimits.com/episodes/season3/307.ht
http://theouterlimits.com/episodes/season4/418.ht
Let's see, you are comparing our solar system to other galaxies? You must realize that the scale of a solar system in relation to the scale of a galaxy is unbelieveably small, right? Ie., there are a (suitably big number) of solar systems in our galaxy alone.
Think of it this way, when you look at a picture of a galaxy, and you see the fuzzy white haze, that haze is (to quote Dr. Sagan) billions and billions of stars.
Now step back, and look at a Hubble Deep Field photo. What do you see? A (suitably large number) of galaxies each of which contains a (suitably large number) of stars/solar systems.
If you really consider the scale of the universe and the scale of time that the universe has been around, it seems pretty obvious that there is a lot of life out there.
The reason we don't have the Star Trek thing going on is that wonderful little thing called "c". That, and I guess they are all trying to learn English...
A house divided against itself cannot stand.
as /. users rush to see who can excel the other at sophistry. The rules are simple.
Now, let the games begin!There are NO aliens, besides those from Mexico, anywhere near Area 51. How do I know, because if creatures are smart enough to travel outside of their light cone, they are smart enough to be able to watch our tv. This has two effects, 1) you can learn a lot about humans by watching tv, and I'm not just talking about Magnum PI, but how about the neurosurgery or opthomology grand rounds you can probably watch if you live near a university. 2) We've made it abundantly clear, that if you're an alien and you set foot on our world, we will try to kill you, we might be sad about it, have a moderately atractive woman in her thrities fuck you, or we might just pre-emptively break out the big firecrackers in the effort to change our entry to "mostly harmless."
It just so happens that part of maintaining a credible threat is to make it difficult for the ones enemies to precisely ascertain one's capabilities. This is why places like area 51 are necessary. That people watch Independance Day (OF ALL THE FUCKING STEAMING LOADS!) and think that "Hey, if Randy Quade plays a character who says he was ass-raped by aliens who are we to say it didn't happen..." is proof that a program of euthenasia tied to intelligence testing isn't entirely without merit. Why the hell you people can't satisfied with rubbing quartz on your chakras and keeping your retardation to yourselves I'll never understand.
And the moderators. What the hell. "Yeah, maybe there are aliens who traveled a million trillion miles to scare farmers shitless and turn cows inside out. Who's to say...?" GOD DAMMIT!
Detecting a simple content-free transmission would be a great start as you at least have somewhere to focus your investigation.
After that it's probably just a matter of looking hard enough.
Boffoonery - downloadable Comedy Benefit for Bletchley Park
Comment removed based on user account deletion
That's almost exactly what the movie suggests: that we are a message and we can pass the same message onward. Won't say too much lest I ruin the movie for yall though, as much as I realize it has but a small chance of ever making it to the states. (wonders about the prospects of Cutie Honey in the same vein.)
My life in the land of the rising sun.
It's bizarre. The universe could be teeming with life, or it could be utterly, completely barren save for us, and both alternatives would look pretty much the same to us.
Communication modes: Our communications are getting more focused, more noiselike (anyone remember what 300 bps sounded like compared to 56K compressed?), less tangible. Maybe the signal came 500 years ago. We couldn't have heard it. Couldn't have. At least the Professor on Gilligan's Island had a radio - coconuts wouldn't have worked. You can't hear radio without a radio (or finely-tuned braces). Who knows what the next physics breakthrough in modes of communication will be? Something quantum? Gravity-related? When it arrives, and if it's better, we'll switch over to it wholesale, and guaranteed we don't have receivers for it at present. Who knows what aliens would be sending their messages with?
Lucky in the life lottery: Perhaps it's easy for life to take hold on a planet, but maybe we're lucky to have had relatively complex creatures survive the multiple catastrophes. Folks sometimes theorize that Jupiter has protected us from some major calamities just by being big and in a further orbit, acting as dustbuster. Maybe life was seeded here from elsewhere. Wouldn't even have to be an organism - just a decayed crappy chunk of RNA-esque material would do for initial seeding purposes, and it would only have to happen once - one intact chunk out of millions of rocks. It took a heck of a long time to evolve multicellular organisms - the number just boggles the mind. Perhaps it's just that hard to evolve anything past single-cell organisms.
Planets: There seem to be a significant number of planets around. The program Celestia keeps a semi-current list of the detected planets and systems (so you can have fun visiting). Some of them, though, seem like there are gas giants way too big, or way too close to the sun, or are in a funny configuration. That's likely not conducive to life.
Age of the universe: I'm guessing, according to an increasing number of observations of late (mostly from the Hubble), that the universe is a lot older than we've been theorizing over the past few decades. The older it is, the more likely extraterrestrial life becomes.
The Ultimate Find: If we found someone, something out there, it would be the greatest discovery... well, practically ever. At least, "are we alone?" is something we've been asking for so long, and actually having a definitive answer would be amazing.
I think the voyages to Mars and (soon) Titan will inspire a new generation. Gads, if we can be that surprised in our own solitary back-yard...
I don't know if we'll find anything out there. I remain hopeful, but I certainly don't have "faith" in anything being out there.
-- Ritchie
Binary geeks can count to 1,023 on their fingers
The idea here seems to be that at some point we'll just decide to abandon the whole RF spectrum because we have better mechanisms of comminucating. This is implausible to the point of silliness. We *will* have better mechanisms, but the RF specrum is still there, and still as usable as it ever was, and if no one is using it, why, it will be very cheap. So people *will* use it, of course.
Imagine, for instance, that UHF TV goes away, and non one wants the spectrum any more. Now you can build a local TV system for the cost of a transmitter (which you can get as cheap surplus). So lots of people will do that, so there will be lots of use of the UHF spectrum. It will just be by people doing more interesting thigns than it was before.
...just don't shoot the messenger.
Kjella
Live today, because you never know what tomorrow brings
The beauty of this scheme is that ET wouldn't have to visit Earth to implant the message. A lot of junk DNA consists of genomic fragments inserted by viruses over the course of evolution. An alien civilisation could, for negligible cost, dispatch tiny packages across the galaxy, loaded with customised viral DNA. The cargo would be designed to infect, without harm, any DNA-based life it encountered.
It's patently foolish to believe an intelligent species would try to write a message in the genes of a developing species remotely from another star in the blind hopes that the virus doesn't wipe out the entire population instead. It's just silly. And who's to say which species the super intelligent shades of blue wrote the message in? Perhaps they thought another species altogether was bound to become dominant on this planet instead of man.
Wait! Could THIS be the real reason the dinosaurs went extinct! (^_-)
Fun with Inkwell | www.coo
Suppose we picked up a signal from some ET and that there was no doubt, scientifically speaking, that it came from ETI. At least half the world doesn't believe in science, so if you're hoping that some of the more narrow-minded religions in the world are going to suddenly snap out of their narrow mindedness, I wouldn't count on it. Just look at the amount of scientific evidence they already manage to ignore or discount. Probably several new and conflicting religions would be founded by people claiming to have found some "divine" interpretation of the ET's message.
Maybe you're hoping the ETs could tell us something that would advance our technology. Given how many of us subscribe to irrational world views, it seems to me that would be damned irresponsible of them. Sort of like throwing gasoline on a fire.
My bet is the first communication detected from an ETI will be a question, something they want to know, or something they want to make sure we know before they say anything else. If our world was enlightened enough to support broadcasting to the stars, rather than just listening, I think we'd ask a question. Asking a question implies you've developed the patience to wait for a reply, which, for light-speed communication at least, is a lot of patience!
The purpose I see in SETI is to find a radio source, possibly unintentional. As another poster suggested, maybe we'll receive their version of the NORAD system or some high-intensity pulses from an intergalactic war. Whatever the signal we receive is, if we can associate it with probable intelligent life, then we could send them something they would be unlikely to miss. I wonder what an ultra-high-powered laser directed at their planet would appear like to them? Of course, this assumes that they can see in our visible spectrum. Perhaps it would appear as a dim star blinking in their sky, visible to some advanced observation system. Meanwhile, some random alien orbiting our planet would be sliced in half by our communication attempt.
The concept that just because our use of radio is supposedly going to decline over the next 100 or so years any possible alien civilisation is already beyond radio, is pretty weak.
I think the duck-billed platypus is all the proof we need that aliens have messed with Earth.
Yet another bogus attempt to inject some credence to that hoary ghost of ID. No, there is no "message" in our DNA other than the message of how to make and use cell parts.
This is the last friggin' retreat the ID'ers can have. The last bastion of that stupid concept of "irreducible complexity". Couldn't have your way with the eye? Couldn't make the flagellum work for you? Now, trying to encode some decipherable message in the DNA? Yeesh.
Been watching that Star Trek movie too many times.
Prove it. Seriously, if you believe that Seti is a waste of money, prove that there are no aliens and hence no need for Seti.
Seti is an experiment. A massive experiment that may prove to be fruitless, but if the big payoff does come about I think that the money will be well spent.
--Andrew Howard
> Meanwhile, Paul Davies writes that we should be conducting SETI in our DNA.
Let's see, we're looking for an unspecified message in an unknown language spelled out in an unknown coding... Yeah, I bet you can 'find' any kind of message you want in there, just like the silly Bible Codes thing. The only surprise is that k00ks haven't already been making their claims.
Sheesh, evil *and* a jerk. -- Jade
You bullheaded humans think you have it all down pat, don't you?
The sad truth is that my planet found your planet from the leaked signal of an '802.11b' device owned by Dave Stewart in Provo, Utah as he was attempting to download a copy of Blue Oyster Cult's Don't Fear The Reaper song. But soon no other intelligence will be able to find your planet due to the decline in the P2P that was a beacon in the long dark night of space. You see, it's the legal dickering of the RIAA that is more a threat to your society than high powered lasers... so sad.
Dedicated Cthulhu Cultist since 4523 BC.
Rather than humans being "Children of the Gods", Zindell has a few of us becoming "gods" and makes an almost convincing case that it would be an inescapable development in a universe with FTL travel.
Paul Davies usually does a pretty good job of representing the perspective of mainstream physics, even adding a few details from his own work, but this time he really seems to have gone out on a limb. While it's a great idea for a SciFi plot, it isn't going to take too many more species' genome maps to make the null hypothesis look very safe.
-- Our systemic servants do not good masters make.
As soon as the alien measures anything about his photon to determine if it's still entangled, Boom! Entanglement is lost. Besides, you cannot determine whether it's entangled without knowing our results on Earth, which he would have to get using some kind of conventional communication signal, and then do some statistical analysis comparing our results to his.
Music speeds up when you yawn, but does not change pitch.
More and more of Earth's communications use cable and satellites, with no radio-frequency leakage to space.
Why would there be no radio-frequency leakage to space using satellites? Some of the signal sent down to earth probably bounces back to space. More importantly, most of the radiation beamed up to satellites goes right into space! There's no way those beams are so narrow that they only hit the satellite's receiving antenna...
SETI is a neat concept and it's logical. That means any alien species would have figured it out as well, and would first be listening for signals directed to *them* before they actively pick a target to transmit to, no matter the technique. Picking a target at random to direct some sort of advanced transmission -> to is pretty expensive and silly, you would want to know that the civilization is advanced enough to understand and to reply to your transmission. Seems like it anyway. It's a catch 22, who goes first?
It could be we have a host of semi advanced civilisations like ours, all sitting around in passive reception mode, waiting for someone to contact them.
...a post consisting only of a single non-alphabetic character, getting modded to +5.
Truly we live in amazing times.
-CausticPuppy "Of all the people I know, you're certainly one of them." -Somebody I don't know
Meanwhile, Paul Davies writes that we should be conducting SETI in our DNA. In turns out that an alien message designed to last millenia should be 'inside a large number of self-replicating, self-repairing microscopic machines programmed to multiply and adapt to changing conditions', otherwise known as living cells. Are we the message?
This was a Star Trek: TNG episode. I distinctly remember Romulans, Klingons, the Federation (and perhaps a couple other species) all fighting over some secret weapon they had discovered in human DNA when it turned out to be a holographic image of a common ancestral species that had seeded the planets. It was probably the second season.
If we were the message, it would have long ago mutated as to be undecipherable. The message was destroyed by SG-1 and the those gray aliens in last seasons Stargate. Seriously, DNA wouldn't be my choice, but a self replicating nanobot designed to reproduce with extreme fidelity would be more suitable for a message. Unfortunately, uncontrolled replication could have disastrous results.
Paul Davies is a creationist. Sorry, but I'm not going to take the advice of a guy who honestly thinks the universe is 6,500 years old.
How would we know if there was a message in our genomes? Presumably ET would make it easy for us to spot. Some sort of in-your-face pattern would be best, something that stood out from the random scatter of genetic letters.
I would posit that an ET intelligence smart enough to create a pattern in our DNA would also be smart enough to make the evidence of their existence readily apparent to even those without the ability to decode DNA. I mean, if the point of sending a message is to communicate, why would you require such sophisticated techniques to understand it, with the attendant risk of misinterpretation?
Replace ET with God, and you've got a good paraphrase of the "intelligent design" argument for God's existence.
I think what irks me the most is the assumption that aliens are trying to contact us. When we think about communication, there are some interesting principles:
- The sender of a message fulfills some need in sending the message. Perhaps it is a call for help; perhaps "they" need some more friends.
- A message is always sent with a reasonable expectation that the recipient will be able to understand it.
- The sender usually wants some sort of response from the recipient, even if it is merely an acknowledgement.
This leaves us with some fundamental problems regarding ET's contacting us with "sophisticated" techniques:- An alien intelligence seeking to make contact with other civilizations would probably choose the most easily recognized form of communication, not one which required sophisticated technology or a considerable degree of intelligence to decode.
- What purpose would such a message serve? If they are more advanced technologically, why would they contact us - we don't have anything that they need? If less so, then we would be able to decode their messages with ease.
- If "they" are sending messages, then surely they must already know, or strongly suspect, our existence. If this is the case, then why don't they already know how to communicate with us?
It would seem to me that if aliens were trying to contact us, we would have known it by know. I suspect that if SETI discovers any "intelligent signals", we'll come to discover that they were not intended for us to decode. Perhaps some alien military communications, or ARIA (Alien Recording Industry Association) encrypted music broadcasts, etc...Just a rhetorical exercise here: Would God qualify as the sender of such a message?
With what we know now, only our Creator would possess the knowledge of our existence, the desire to communicate, and the means to do so. I wonder if this occurs to the SETI team, or if they are trying to find God in outer space...
The society for a thought-free internet welcomes you.
Maybe the universe isn't old enough. Seriously! Stuff like carbon, iron took multiple generations of stars (birth-to-supernova) to produce. Intelligent life that appeared approximately before the existence of Sol/Earth would have lived and died without the means to forge swords, much less spaceships. I believe our star is a fifth-generation, although my head is fuzzy on that number.
Human beings may just be the first creatures who have the chance at interstellar civilization. Either that, or we are going to be part of the first wave, developing simultaneously.
Together, we will drive the rats from the tundra.
No no no! Aliens communicate through a series of large stone monoliths! Don't you guys pay attention?
"We shall party like the Greeks of old! You know the ones I mean." - HedonismBot
Now from the car's perspective, the light is moving away from it at C, but it's moving forward at .5C, so the light is only getting closer to the observer at .5C. Hence it takes two minutes to reach the observer. At T+1 minute, the light has not reached the observer. So the guy in the car is surprised by the announcement that it has, and sends back an instant communique for confirmation.
"Confirmation?" asks the observer, "I haven't sent you anything yet!" After all the light has not yet reached the observer, so how could he have sent the communication?
You're assuming there's such a thing as absolute time, which Special Relatively disproved.
So there is no such thing as T time. There is O(T) - Observer time. And R(T) - caR time. Let T0 be the time when the car flashes its headlights, and T1 be the time when the light from this flash reaches the observer.
So the car flashes it's headlights at R(T0). The observer sees the flash at O(T1). The observer then immediately sends an instantaneous message to the car, which is recieved at R(T1).
To both parties, at the time T1, the light ray from the headlights has reached the observer. The difference is that (R(T1) - R(T0)) > (O(T1) - O(T0)).
Your thought experiment assumes that there is a "universal time". So that one minute for the car is the same as one minute for the observer. This is incorrect.
Or perhaps the only message we'll ever see from them would be a giant laser beam that instantly fries our planet, making everything in this discussion irrelevant.
:-)
Maybe that's how you get modded down on an interstellar slashdot as -5 flamebait
The best idea I've seen for getting the attention of ET's is to dump a few tons of elements into the sun that do not occur naturally, such as technetium. Basically, it's nuclear waste, and when an alien astronomer looks at our star, they'd see spectral lines of elements that could only be produced in a nuclear reactor...A sure sign of intelligent civilization.
1. The "creative intelligence" you speak of could just as easily be the blind process of natural selection. Just add a couple DNA pairs every 50 million years or so and you've got more than enough time to come up with a 6 billion-bit quaternary code, more or less optimized for the present, with a nice long "history of our evolution" message attached to it. This process requires no supernatural forces.
2. Depending on how you define God, it would seem exceedingly unfair for him/her to reveal themself through sub-microscopic code. There are millions of people living today who have no clue what DNA is, and BILLIONS of people who lived in ages past before DNA was even discovered. While the argument you post may hold true for some weird alien race or unthinking/uncaring God, it definately cannot be extended to any worshippable, caring, and fair Creator of sorts, having excluded the vast majority of humanity thus far with the choice of how to deliver the message.
To me, the idea that any kind of supernatural forces are in a dramatic ballet with mankind is the epitome of aristocentrism.
The Law of Accelerating Returns by Ray Kurzweil
It offers a very well reasoned argument as to 1) why the technological singularity must occur, and 2) why SETI is likely a failure. Actually, I would suggest reading Vernor Vinge's writings on the singularity, then read Kurzweil's work above.
One should then read the story (posted at k5?) called "The Metamorphisis of Prime Intellect".
Finally, read Albert-Laszlo Barabasi's book "Linked" (network theory), Kevin Kelly's "Out of Control" and Steven Johnson's "Emergence" (emergence theory), and Stephen Wolfram's "A New Kind of Science" (The Principle of Computational Equivalence).
There are many more references, both fictional and non-fictional (for entertainment purposes only, I also suggest the anime "Serial Experiments: Lain") - but these which I have listed detail a staggering breadth of information which, after you have digested it and left it to simmer in your mind, just might change your opinions and worldview in radical directions.
Lastly - a plea for help: Does anybody here know of any papers or references from reputable sources which discuss why the singularity can't occur, or is wrong in some manner? I have only read one side of the debate, and I would like to hear the other.
Reason is the Path to God - Anon
Since radio waves and light are basically the same (electromagnetic waves), the problem is not that of possibility, but basically an energy issue...
photon energy is proportional to frequency
So for a given amount of energy you can get either more photons at a lower frequency or fewer photons at a higher frequency.
Since visible light is in the THz range (10^12) and radio waves are in the say MHz range (10^6), that's a factor a million less photons emitted per unit of energy.
Since we are essentially detecting a bunch of photons, this is the gist of the problem.
Of course it follows that the odds of finding one of a million needles in trillions of haystacks is easier than finding 1 needle in a trillion haystacks...
Of course if you are living on a pulsar, then energy (from gravitational collapse) is not a worry (pulsars tend to emit frequencies all over the spectrum from radio up to x-ray), but I don't think "intellegent" civilizations are going to be tossing around that much energy w/o thinking about it.
Note that a signal from a pulsar is very different from an omnidirectional phase-coherent electromagnetic "pulse". A pulsar spews pretty much incoherent EM, but from hotspots on a fast spining object (think about a person with a gardenhose spinning around really fast, you'll see how a stationary observer will see "pulses" of water drenching her when in fact the garden hose is just spraying incoherent water).
However, it is technically possible to generate a reasonably coherent, mostly omnidirectional EM pulse from a process known as superfluorescence.
I suppose it's feasible that this would be able to be repeatable enough to generate a pulse train (imagine a spherical lasing cavity around a superfluoresenct object). For some basic info on this, check this out...
http://ist-socrates.berkeley.edu/~lvov/OSF.html
However, given the "energy" argument above, I doubt any intellegent aliens would have turned on a beacon like that (Did you see the movie independence day? Maybe turning on a beacon isn't such a great idea)...
The easiest artificial signal to differentiate from natural noise are signals with frequency spikes. FM and AM radio have good frequency spikes. VSB modulation which is used in television broadcasts has a decent spike. These are pretty easy to detect as manmade.
These days the trend of RF technology is moving from spiked spectrum to spread spectrum modulations that looks more and more like noise.
For example lets take TV from an alien perspective. There is a move from VSB picture and FM voice to spread spectrum transmissions. With FM and VSB the cells on same frequency must be pretty far away from each other not to interfere with each other. And to get a good picture the transmision must be high over the noise floor. The alien observer would see some strong spikes on his spectrum analyser moving along the frequency as earth turns (dobbler). Now with spread spectrum the signal is spread evenly over the spectrum so no spikes. And because spread spectrum signals don't interfere with each other so easily the cells on same frequency will be closer together. So the alien observer would see more transmitters sending evenly spread transmission over another and another and another,each with a slight changing frequency shift to each other because of dobbler. Impossible to differentiate from noise.
So new technology is changing earth from spiked hedgehodge to fluffy ball, looking just like a natural noise source.
In future the detection bubble may thicken because of microwave power transmission. If there will be solarpower spacefarms, there will be new spikes with enough oomph to an alien observer.
well, we all know what's programmed in there.
The answer is 42.
-- All your bass are below two Hz