Finding frugal aliens: 'Benford beacons' concept could refocus search for intelligent extraterrestrial life

Jul 20, 2010 by Tom Vasich
Astrophysicist Gregory Benford — standing before the UCI Observatory — believes an alien civilization would transmit “cost-optimized” signals rather than the kind sought for decades by the SETI Institute. Photo: Steve Zylius

(PhysOrg.com) -- For 50 years, humans have scanned the skies with radio telescopes for distant electronic signals indicating the existence of intelligent alien life. The search — centered at the SETI Institute in Mountain View, Calif. — has tapped into our collective fascination with the concept that we may not be alone in the universe.

But the effort has so far proved fruitless, and the scientific community driving the SETI project has begun questioning its methodology, which entails listening to specific nearby stars for unusual blips or bleeps. Is there a better approach?

UC Irvine Gregory Benford and his twin, James — a fellow physicist specializing in high-powered - believe there is, and their ideas are garnering attention.

In two studies appearing in the June issue of the journal Astrobiology, the Benford brothers, along with James’ son Dominic, a NASA scientist, examine the perspective of a civilization sending signals into space - or, as Gregory Benford puts it, “the point of view of the guys paying the bill.”

“Our grandfather used to say, ‘Talk is cheap, but whiskey costs money,’” the physics professor says. “Whatever the life form, evolution selects for economy of resources. Broadcasting is expensive, and transmitting signals across light-years would require considerable resources.”

Assuming that an alien civilization would strive to optimize costs, limit waste and make its signaling technology more efficient, the Benfords propose that these signals would not be continuously blasted out in all directions but rather would be pulsed, narrowly directed and broadband in the 1-to-10-gigahertz range.

“This approach is more like Twitter and less like War and Peace, ” says James Benford, founder and president of Microwave Sciences Inc. in Lafayette, Calif.

Their concept of short, targeted blips — dubbed “Benford beacons” by the science press — has gotten extensive coverage in such publications as Astronomy Now. Well-known cosmologist Paul Davies, in his 2010 book The Eerie Silence: Renewing Our Search for Alien Intelligence, supports the theory.

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James Benford discussing beacons

This means that SETI — which focuses its receivers on narrow-band input — may be looking for the wrong kind of signals. The Benfords and a growing number of scientists involved in the hunt for extraterrestrial life advocate adjusting SETI receivers to maximize their ability to detect direct, broadband beacon blasts.

But where to look? The Benfords’ frugal-alien model points to our own Milky Way galaxy, especially the center, where 90 percent of its stars are clustered.

“The stars there are a billion years older than our sun, which suggests a greater possibility of contact with an advanced civilization than does pointing SETI receivers outward to the newer and less crowded edge of our galaxy,” Gregory Benford says.

“Will searching for distant messages work? Is there intelligent life out there? The SETI effort is worth continuing, but our common-sense beacons approach seems more likely to answer those questions.”

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More information: www.liebertonline.com/toc/ast/10/5

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alq131
3 / 5 (3) Jul 20, 2010
If the assumption is that the place to search is the center of the galaxy and aliens assume the same thing, we are in a pretty bad location being in an outer arm of the galaxy. It would stand to reason that aliens would send their signals toward the center of the galaxy too. We might then only see signals from a slice of the opposite side of the galaxy passing through the center and out to us.
Ballgame
3.8 / 5 (5) Jul 20, 2010
That isn't the assumption. The premise of your argument is flawed. The prevailing wisdom is that the center of the galaxy has too much radiation for organic, sentient beings to survive/evolve and far too much interference for us to search for signals effectively.

Mostly, we have been searching stars within our local stellar neighborhood for signals.

Besides which, searching for signals 30,000 light years away (center of the galaxy) is far less effective for a back and forth conversation than searching 10-50 light years away. A response to the center of the galaxy would (most likely) reach our "friends" after our civilization is destroyed (30,000 years ago we were scraping the ground with flint tools during an ice age).
jimbo92107
4 / 5 (2) Jul 20, 2010
Advanced alien civilizations would have thought through the issues of long distance communication between civilizations and concluded that it was a waste of time and resources. Any information you send out must be assumed to be a one-way process. If so, then what do you send, a radio signal that says, "Hello" for some brief time? That's stupid, which we're assuming advanced civilizations are not.

More probably, an advanced civilization might send information embedded in some tough, physical form, like a spore with jokes in its DNA. Well, maybe not jokes - you know humor doesn't translate well between cultures. Has anybody checked the junk DNA of viruses and spores for traces of the pi sequence?
alq131
2.5 / 5 (2) Jul 20, 2010
But where to look? The Benfords’ frugal-alien model points to our own Milky Way galaxy, especially the center, where 90 percent of its stars are clustered.
my point was only that if aliens are using unidirectional signals _and_ they think the same thing--that the center is where to look, or where to send their signals, then we wouldn't even see a signal from next door if it is a beam towards the center. The argument of the article is that aliens might be using unidirectional beams rather than omnidirectional broadcasts. It would stand to reason that then we would only "see" signals from the other side of the galaxy that line up with us and the center...and as you point out, a very difficult task with the distances and interference.
BigTone
3 / 5 (4) Jul 20, 2010
It's fun to read one article on this site talking about how we don't know what most of the universe is made of and our dark matter theories don't have fun with gravity theories vice versa... Then you read about lensing and ways of cheating the system to find planets... Then you read this article and all of sudden we think we have a clue about how advanced civilizations might communicate and we don't understand the medium (space) in which they are allegedly communicating or not communicating through... I'm not following the jumps in logic
KBK
1 / 5 (3) Jul 20, 2010
Look into Nickolai Kozyrev's scalar detectors that analyze time-invariant waves that penetrate everything, except, oddly enough... aluminum. He tried blocking the waves with the entire table of elements and aluminum is the only thing that stopped it. As well, the time or 'speed of arrival' of the wave is outside of time, meaning instantaneous, to his measurement and methodology of such.

Outside of time and penetrates everything and anything.

And that is where you will find their communications.

Won't you?

You won't know until you look it up.

Too add... 'open public science' is always decades behind private, military and/or government research, so consider that I do know what I'm talking about and begin researching it. 'Public science' is not the bleeding edge -and never will be.

Here comes the low marks on this post! Go ahead, like water off a duck's back..I'm used to it and it means nothing to me. I'm talking to the few who are paying attention. Not the rest.
james11
not rated yet Jul 20, 2010
Jimbo, I have heard about that before and I think it is very interesting.
Sanescience
4 / 5 (1) Jul 20, 2010
There is another possible conclusion, being detectable is risky and the smart aliens stay quiet, while the noisy aliens get "found", and never heard from again.
antialias_physorg
4 / 5 (2) Jul 20, 2010
Aliens likely know whom they are broadcasting to (especially when trying to broadcast over interstellar distances). So if there are aliens then there is likely a lot of very directed point-to-point transmissions going on with power output proportional to the distance.

Since we are not within the line of sight of such a transmission (and insisde the relevant range) the galaxy could be filled with an abundant amount of messages and we'd never get a whiff of it. I find the assumption that aliens are transmitting in all directions at max power dubious at best. Why would they do that?

All this is assuming they don't have something better than radio waves. If they have close to speed of light travel (or even FTL) then courier drones are likely to be better than transmissions. Also this would be safe from eavesdropping (short of physical interception of the drone)

SETI is trying to listen for spacefaring-but-technologically-hopelessly-backwards-aliens. That never sounded right to me.
Skeptic_Heretic
4.3 / 5 (6) Jul 20, 2010
Look into Nickolai Kozyrev's scalar detectors that analyze time-invariant waves that penetrate everything, except, oddly enough... aluminum. He tried blocking the waves with the entire table of elements and aluminum is the only thing that stopped it. As well, the time or 'speed of arrival' of the wave is outside of time, meaning instantaneous, to his measurement and methodology of such.
Not this shit again.
Rdavid
not rated yet Jul 20, 2010
RE: "(30,000 years ago we were scraping the ground with flint tools during an ice age)."

Perhaps we ought to start there: how would we communicate with such a flint-scraper?
charleslucas
5 / 5 (1) Jul 20, 2010
Look at the leaps and bounds occurring in the sciences of planet detection. Just in the last few years we have been able to reliably detect not only that planets orbit certain stars, but what the chemical makeup of their atmosphere is. If we extrapolate that an older civilization has done this to an advanced degree, we could assume that any civilization that can pick out light from our star could determine that our planet has life. If they're actively monitoring, then any civilization within about 100 light-years could likely tell by the increased levels of CO2 in our atmosphere (corresponding with the start of the industrial revolution), that we've reached a level of technology where we might be expected to have radio receivers. Then they could start broadcasting to us directly.
antialias_physorg
4 / 5 (3) Jul 20, 2010
Then they could start broadcasting to us directly.

For what point and purpose? Seriously: aliens that are that far ahead have no reason to communicate with us.

Do we try to talk to ameoba or ants? No.

The Benfords’ frugal-alien model points to our own Milky Way galaxy, especially the center, where 90 percent of its stars are clustered.

The center is a dicey place. Stars close together (which means lots of radiation) and a very high probability that one of them goes bang every few thousand years (which sterilizes anything within a few light years radius). If alien life is anything as fragile as ours then it certainly isn't anywhere near the center of the galaxy.
yyz
not rated yet Jul 20, 2010
This sounds like a gigahertz version of optical SETI: http://www.seti.o...?pid=330

The idea of directed communication by ETI has been around for a while. This 1998 paper looks at technical aspects of optical(& IR) SETI: http://seti.harva...tech.pdf .Dedicated telescopes for optical/IR SETI are being built or already exist. And suitably equipped amateur astronomers are also joining the search (as is, IIRC, SETI@Home). Seems like a longshot IMHO, but a gigahertz search, if you can raise funds, why not?
FredJose
1 / 5 (7) Jul 20, 2010
Just to rile the evolutionists: Who says there are ANY aliens out there?
God made the earth to be inhabited by those bearing his image and they sinned far too early for any migration to other stars and planets to have happened.
Hence, we are alone in the universe created by God.
Christ couldn't have died for any alien since such an alien would possibly not have sinned - sin is an earth original. Yet ALL of creation was put under the curse because of man's sin, and it would have been unfair for aliens to suffer because of man's sin.
Thus - Christ died for the redemption of man and the rest of un-inhabited creation alone.

There aren't any aliens so it would save a lot of energy to stop looking for them. Of course, if people insist on looking, we might discover new ways to communicate using the new-found tech we're busy inventing.

OK, you can throw stones and bricks and flints now.
otto1923
Jul 20, 2010
This comment has been removed by a moderator.
yyz
not rated yet Jul 20, 2010
All searches for ET communications today look for signals at certain wavelengths of the electromagnetic spectrum. But more 'exotic means' of communication have been explored. One involves Cepheid variable stars: http://arxiv.org/...39v2.pdf

From the abstract: "We propose that a sufficiently advanced civilization may employ Cepheid variable stars as beacons to transmit all-call information throughout the galaxy and beyond. One can construct many scenarios wherein it would be desirable for such a civilization of star ticklers to transmit data to anyone else within viewing range. We propose that these (and other regularly variable types of stars) be searched for signs of phase modulation (in the regime of short pulse duration) and patterns, which could be indicative of intentional signaling." Out past the Virgo Cluster!

con't
yyz
not rated yet Jul 20, 2010
Another recent paper explored using neutrinos for interstellar communications: http://arxiv.org/...29v2.pdf

Abstract: "We examine the possibility to employ neutrinos to communicate within the galaxy. We discuss various issues associated with transmission and reception, and suggest that the resonant neutrino energy near 6.3 PeV may be most appropriate."

Both are speculative studies of course. But I think they show willingness to explore new ideas on the topic of interstellar communication.

"He tried blocking the waves with the entire table of elements and aluminum is the only thing that stopped it." Time to exchange tin foil for the aluminum foil hats? ;)
Skeptic_Heretic
4 / 5 (4) Jul 20, 2010
Just to rile the evolutionists: Who says there are ANY aliens out there?
God made the earth to be inhabited by those bearing his image and they sinned far too early for any migration to other stars and planets to have happened.
Hence, we are alone in the universe created by God.
Christ couldn't have died for any alien since such an alien would possibly not have sinned - sin is an earth original. Yet ALL of creation was put under the curse because of man's sin, and it would have been unfair for aliens to suffer because of man's sin.
Thus - Christ died for the redemption of man and the rest of un-inhabited creation alone.

And now that you have that out of your system, the rest of us will talk about the article, and other things that aren't entirely ridiculous.
FullyAutoMagic
5 / 5 (4) Jul 20, 2010
I realize that waiting for a corner and attempting to jump onto the "conversation" would be prudent; but I'll simply limit myself to this. Go SETI and all other "space explorers." What you do is important beyond what the average person understands. I'll qualify this by saying this is not my field of expertise, nor do I claim to know much about it past whats contained in the trade publications and magazines.

That said, keep searching. Always keep searching. Science (IMHO) is searching, from the smallest to the largest.
Nartoon
not rated yet Jul 20, 2010
What if the Aliens are only listening too, and not transmitting?
james11
1.3 / 5 (4) Jul 21, 2010
I was outside tonight on the phone in my driveway and when I hung up I looked up at the sky and saw a ufo. Dont know if it was alien but It was definitly advanced. It moved fast and I mean fast. Much faster than a plane, it looked like a shooting star but not as fast. I actually got a really good glimpse of it, it was up pretty high but lower than normal planes.
james11
1 / 5 (2) Jul 21, 2010
Are there people that use high tech cameras to record the sky at all? I find it hard to believe after tonight that no one has found anything conclusive. I am positive that this was extremely advanced.
james11
1 / 5 (2) Jul 21, 2010
It sucks that I have no evidence but I could probably figure out the speed if someone helped.
Rawley
4 / 5 (1) Jul 21, 2010
james: could have been a satellite. I watched the iss go over one day right at dusk, took about a minute from when I first saw it to cross the day/night terminus, plus it was extremely bright which makes it look quite large and closer than it actually was.
james11
1 / 5 (2) Jul 21, 2010
Not a satellite I am positive it was very fast and fairly close
Mayday
5 / 5 (1) Jul 21, 2010
The smart aliens will be very quite, having learned(as we have) that all cross-civilization contact results in the calamitous destruction of one of the societies. Some will go through brief periods of "accidental" broadcasting(like us). Eventually, we will hear those from other galaxies. Locally, I would always assume that any "advanced" civilization that is actively looking for friends is phishing for conquest. Should human-alien contact ever occur, do not expect a ticker-tape parade. Be careful, out there.
ArtflDgr
not rated yet Jul 21, 2010
Waste of time as any such source can be detected by wide field monitoring... the bigger point is that they assume another species would WANT to find others and then would spend precious resources to send a message to someone that they can never know arrived due to distance.

its a waste of tax dollars other than SETI

given the distances involved the lag between messages would be too dysfunctional...
wowfunguy
not rated yet Jul 21, 2010
Using microwaves to talk to ET is already as obsolete as communicating with 2 tin cans on a string! Optical (lasers) would be far more effective.
However my bet is on QEC (quantum entanglement communication) A civilization even a few years more advanced may have already established the "Galactic Web" with QEC.
Mayday
5 / 5 (2) Jul 21, 2010
Smart aliens would soon learn to shroud all signals to look like background noise or natural sources. You want to "find," not "get found." You think confidentiality and trust issues exist on facebook, wait until you log onto the "Galactic Web," brother.
wowfunguy
not rated yet Jul 21, 2010
Good thought, and maybe so...but my bet is that sufficiently advanced aliens that didn't destroy themselves might be more benevolent....
yyz
not rated yet Jul 21, 2010
If ETI refrains from actively communicating their presence, means to passively detect ETs have been explored. A paper earlier this year looked at several possible ways to detect "interstellar archaeological signatures" (Dyson spheres, stellar doping, stellar engineering): http://arxiv.org/...55v1.pdf

While some of these are more speculative and lie in the future, looking for signatures of "non-natural planetary atmospheric constituents" (think Freon, etc.) is or soon will be possible via spectroscopy. This would be similar to what charleslucas posted above, but in this case it is us looking for signatures of a technological civilizations in the spectra of exoplanets. This would be very doable.

A modified Drake Equation is also used to evaluate the challenges among the various scenarios.
yyz
not rated yet Jul 21, 2010
"....my bet is on QEC (quantum entanglement communication) A civilization even a few years more advanced may have already established the "Galactic Web" with QEC."

According to some, we have already been "entangled": http://www.americ...w/153365

"There are over 27 species above in the global fleet or the Star Fleet Command above." (I keed, I keed)
antialias_physorg
5 / 5 (2) Jul 21, 2010
Smart aliens would soon learn to shroud all signals to look like background

Or they simply gear the power output to the distance to the receiver. It's simply wastefull to blast messages at a level that is discernible hundreads of light years past the intended destination. Not even we do this on earth.

And no - our signals from the early days of radio/TV will not be picked up by aliens. At the signal strength we've been transmitting further than 2 light years out the signal strength is already below what a even thoretically optimal receivers could pick up.

Why would we (or SETI) expect aliens to use a lot higher energies during their 'phase of visibility'? I don't get it.
StandingBear
1 / 5 (4) Jul 24, 2010
I'm sure we have already been noticed, and colonized; and our governments have known for many years. The deal is: they spoon feed us some tech once in a while; we keep their presence secret as much as possible and allow bases and listening posts to operate in our system, including our own homeworld. Otherwise, if we wanted we could stop the universe. Physicists who worship Einstein say no two objects can have a relative motion greater than lightspeed. They also say that photons are objects. They say that photons travel at lightspeed. They say that light is photons. So simply send a beacon into space and revolve it in a large circle. Do it from two satelites orbiting at right angles. At some point the beam will be rotating at lightspeed as well, far enough out in space. Then the beam will propagate no further, like a giant light sabre. All matter will then stop in its tracks for it cannot violate Einstein by moving as its added velocity will violate 'c'.
wowfunguy
not rated yet Jul 24, 2010
Well finally, in a civilization a hundred years more advanced than ours,,,,the aliens don't have to be frugal. "Money" will be created by the machines, energy to cheap to measure (like our long distance calls now)doesn't anybody on here read Kurzweil?
trekgeek1
4.5 / 5 (2) Jul 24, 2010
* Aliens already know we are here if they possess tech that is many times greater than ours. We can already find planets from home, there is no increased threat by attempting to contact aliens that can already see us.

*They might want to talk to us for social studies experiments. Every culture, no matter how primitive, has something to teach.
"I have never met a man so ignorant that I couldn't learn something from him."
-Galileo Galilei

* They probably use a method of communication so far beyond what we know, that we could be flooded with transmissions and not even notice. We think it takes a lot of power and time for intergalactic messages to be sent, but that may be the case with our methods only.
PS3
not rated yet Jul 25, 2010
I see no point in searching for anything that is not close enough to matter.So searching the center seems pretty stupid IMO.It is the same with planet searching.Why even bother when you don't even know the scale of things close by with certainty.

UFOs if real are most likely inter-dimensional as that gets rid of the FTL problem.
Milou
not rated yet Jul 25, 2010
We already had communications with aliens. It is called "governments" and they are not listening. Sorry, I had to fit that in:}
james11
Jul 26, 2010
This comment has been removed by a moderator.
Cantrell
not rated yet Aug 01, 2010
I think the idea of having to consider universal economic and even social theories in order to enable communication with aliens is fascinating. Suddenly it's not all about the hard sciences, but about the social sciences, as well. Fascinating stuff.

This article really reminds me of the short story "The Human Legacy Project":

http://www.living...ect.html