≡ Menu

SETI: A Networked Galaxy?

We often conceive of SETI scenarios in which Earth scientists pick up a beacon-like signal from another star, obviously intended to arouse our attention and provide information. But numerous other possibilities exist. Might we, for example, pick up signs of another civilization’s activities, perhaps through intercepting electromagnetic traffic, or their equivalent of planetary radars? Even more interesting, as Brian McConnell speculates below, is the idea of listening in on a galactic network that contains information not just from one civilization but many. As Centauri Dreams readers know, McConnell and Alex Tolley have been developing the ‘spacecoach’ concept of interplanetary travel, discussed in the just published A Design for a Reusable Water-Based Spacecraft Known as the Spacecoach (Springer, 2015). It’s a shrewd and workable way to get us deep into the Solar System. Today McConnell turns his attention to a SETI network whose detection could offer a big payoff for a young civilization.

by Brian McConnell

McConnell

With the revival of SETI funding, it’s interesting to contemplate what we might find if SETI succeeds. One possibility that is especially tantalizing is that first contact would not be with an individual civilization but rather a large scale network of civilizations that is organized not unlike the Internet. This is not a new idea (Timothy Ferris and others have explored this concept) but it is one that should be considered seriously. Assuming that communicative civilizations are commonplace, a big if of course, a decentralized or mesh network will be the most time and energy efficient way for them to organize their communications.

Consider the energy cost of sending a unit of information from one edge of the galaxy to the other (~ 100,000 light years) via direct means versus a peer-to-peer relay system. The savings ratio can be estimated as:

daveragewgalaxy

If communicative civilizations are separated by an average distance of, say, 1000 light years, the energy cost of sending a unit of information across the galaxy via relay will be about 1/100th that of direct communication. The energy requirement per link drops off by the ratio of (daverage / wgalaxy)2 but as more hops are required with shorter links, the overall energy requirement drops by daverage / wgalaxy. This is an approximation, but it highlights the order of magnitude improvements in economy, and suggests that if communicative civilizations are widespread, energy economics and other considerations will favor this type of arrangement.

Reliability and redundancy are another important feature of a mesh network. When sending information across such great distances, and with such long transit times, a sender may want to protect especially important information against loss or corruption by sending it repeatedly or by sending it via multiple paths between endpoints. This technique can virtually guarantee that information is eventually transmitted even if the network is damaged, even without the use of sophisticated forward error correction codes. This isn’t to say that an extraterrestrial intelligence will copy the TCP/IP protocol, but it’s safe to assume that someone who is sophisticated enough to build an interstellar communication link will probably be familiar with the characteristics and benefits of decentralized mesh networks.

There will also be benefits to receivers, especially newcomers, as contact with one node will be the same as contacting many nodes, since any node in the network can function as a relay for others. The cost of joining the network is also reduced, as a new node need only establish communication with its nearest neighbors, and can relay messages to and receive information from any other site on the network. Such a network would not merely be a communication system, but also a long term repository of knowledge as important information from long dead civilizations could continue to circulate throughout the network in perpetuity.

800px-Milkyway-summit-lake-wv1_-_West_Virginia_-_ForestWander

Image: The Milky Way as seen from the mountains of West Virginia. Could the galaxy be filled with the traffic of networked civilizations? Credit: ForestWander.

Fermi Implications

The existence of such a system might also help explain the Fermi Paradox, as the most energy efficient mode of operation, in terms of detecting new civilizations, will be for each node to concentrate its detection efforts on its immediate neighborhood using a listen and reply strategy. There would be little point in building powerful omnidirectional beacons that are detectable over great distances, as they would cost far more energy to operate, would have to wait millennia for a response, and would be plagued by duty cycle issues. Better for peripheral nodes to listen for microwave leakage from nearby civilizations as they develop early communication technology, and then target those for active communication soon after they are detected. This sort of strategy would be cheap both in terms of energy and the number of radio-telescopes required at each node in the network, and would offer a high probability of success in detecting new nodes just as they become active, while not wasting energy by transmitting in the blind.

An important point to consider here is that an emerging technological civilization would become detectable independently of any intent to attempt interstellar communication. Indeed here on Earth, the vast vast majority of energy expended on electromagnetic signaling has been for purposes other than Active SETI. It seems likely that most technological civilizations would go through a period where they are microwave bright, even if they later go dark due to transitioning to other technology, fear of ETI contact, etc.

As we would just now be detectable to nodes within about 100LY (80LY is probably a better estimate), we would just now expect to be receiving a response from a node within 40-50LY. It’s possible that rapid changes in atmospheric spectra, as Earth has experienced with the sudden increase in carbon dioxide, might also serve as a early tripwire for attempting active communication, but those could be ambiguous signals with natural explanations like volcanism, whereas a sudden spike in monochromatic microwave transmission points definitively to a technological origin. Viewed from the network’s perspective, this decentralized strategy would enable detection of new sites with the least energy expenditure and the shortest possible lag time between detection and active communication, with the added bonus feature that the first nodes to establish contact could relay stored information from nodes far beyond the initial radius of communication. On the other hand, if the average distance between nodes is large, it may be a long time before the nearest nodes are aware of us, and it may be hard for such a network to become established in the first place.

Choice of Encoding Schemes

Another interesting aspect of a long running galactic communication system is that there will be a natural selection of sorts that favors the message encoding schemes that are most likely to be mimicked. The selection pressure in this case will favor an encoding scheme that is broadly comprehensible (easy to understand the basic design pattern) and flexible (able to accommodate many different types of information via that framework). A transmission that is extremely difficult to parse, for example because of strong encryption or sophisticated forward error correction codes, is less likely to be mimicked than one whose basic design pattern is comprehensible to many receivers, even if it is less than optimal in terms of capacity or error resistance. This leads to the fittest message being more likely to replicate (be mimicked in retransmission) than its competitors. This is also an incentive for civilizations wishing to project influence through remote communication to design messages that peer sites will want to and be able to copy.

The point is not to speculate about what would be in such a message, but how it is organized at a low level. To build a mesh network that can handle many data types, you don’t need a very sophisticated message format, even if some of the data types sent within the message are extremely complex or difficult to comprehend. Typically you break a large amount of data, be it a file or communication stream, into smaller predictably organized subunits which are labeled with metadata, which might include:

  • a frame or packet number : identifies a message segment’s position within a collection, file, stream, etc
  • a collection or file number : to identify a larger grouping of frames, pages, packets, etc
  • an author or sender number : to identify the author or sender of a particular segment.
  • a receiver number : to identify the intended recipient, if any
  • a content identifier : to identify the type of content represented by the frame or packet
  • a blob of data, or payload, that is described by the above metadata

While one could design more complex schemes, the above defines the minimal set of metadata needed to describe something like a mesh network or file system with many files, authors and varying file types. What someone decides to convey with such a system is a different matter entirely, but a mesh network in its simplest form consists of a long chain of | meta data | blob of data | meta data | blob of data | segments with obvious repeating structures.

Implications for SETI

While the basic design pattern of a system like this can be rather simple, it will be capable of delivering data that varies widely in content type and “difficulty level”, and also offers a high degree of durability (important message fragments can be resent out of sequence or sent via multiple paths). Some content types such as rasterized or bitmapped images will probably be nearly universally understood due to their utility in astronomy and space photography, while others that are based on advanced math may be unrecognizable to many recipients. It’s not unlike DNA, whose basic encoding scheme has just four letters, yet can encode for something as simple as an isolated protein or as complex as a human being. That’s one of the interesting characteristics of the fittest message — it should be easy to parse at a low level, yet capable of conveying data types representing a wide range of complexity.

All of this suggests that SETI surveys should be concentrating a portion of their observing time on nearby targets. This also suggests that a large scale network will probably need to find us before we can find it, but will also be relatively easy to spot once it does. This doesn’t exclude other possibilities, and indeed SETI should be trying many strategies in parallel, from looking for distant beacons to Bracewell probes.

Should we encounter a network like this, the implications of that would be nothing short of staggering because of the volume and variety of information that could flow through a system like this. It’s possible that much of that communication will be over our heads. On the other hand, the quasi Darwinian selection pressure on message formats may favor those that are broadly comprehensible, or at least contain elements like rasterized photos that virtually any astronomically communicative receiver can understand, including us.

tzf_img_post

Comments on this entry are closed.

  • Stan Erickson October 9, 2015, 13:02

    What exactly would be the benefit to an advanced alien civilization of having all this information? One can reasonably assume that after a few millennia, science and technology development is done, in all areas, and there would be nothing to learn from another civilization. Having a library of the history of other civilizations doesn’t add anything to a civilization that already ‘knows everything’. Details like what was the name of the 3256th president of alpha phi 5b are simply insignificant to them. I don’t see any justification for translating human emotions like curiosity to advanced alien civilizations, unless you want to also assume that they will not have devised multiple ways to make their lives interesting and fulfilling. For example, they could create historical fiction that was more interesting than any history they could get from another species.
    stanericksonsblog@blogspot.com

  • Alex Tolley October 9, 2015, 13:44

    As you point out at the end, the problem for SETI is worsened, because we will only be able to detect a signal if it is either leaking nearby, or directly aimed at us. How nearby depends on the location of the nearest civ with a network node.

    If such a “galactic club” exists, why assume that the nodes are only located at the civ’s home system or where they have expanded to? Perhaps the most logical approach is to place nodes in every system (analogous to our IoT), which offers benefits in terms of using the nodes to surveil living worlds and communicate locally with smart systems. It would also allow using simple electromagnetic c limited communication locally for primitive civs, but possibly FTL communication between nodes should that be possible. But then we have another problem, analogous to the Von Neumann replicating probes issue. If the logic of highly dispersed nodes makes sense, where are they and why are we not receiving a signal from the solar system? Are they waiting for us to uncover or disturb such a node as in Clarke’s “The Sentinel”?

    If there are civs communicating between themselves out in the galaxy, but also fearful of predators, it makes sense that their communications would be as stealthy as possible, making it unlikely that we could detect them by chance. More likely it would be predators sending out decoy signals to attract our attention and give ourselves away. How could we innocents tell the difference?

    My last thought is that electromagnetic communications, will have a limited communication rate. Low energy certainly, but perhaps quite slow. Would it make more sense to transmit information by physical probes containing large information payloads, perhaps at near light speeds to increase the information rate, which we might imagine could be very high for such civs? In which case SETI should be looking for nearby evidence of drive emissions as discussed in other posts.

  • Steve Bowers October 9, 2015, 15:43

    Contact with an alien species would be good for one thing;
    Inspiration.
    After millenia (or millions of years) of isolation an advanced civilisation might have explored every nuance of their own native culture, and might jump at the chance of new input from alien worlds. Indeed, it is possible that our culture is the most valuable thing that humanity has to offer; The Mahābhārata, Jane Austen, Age of Ultron, Spirited Away – they might value this more than anything else we have to offer.

  • Chris October 9, 2015, 15:48

    Maybe the handshake protocol would be different from the everyday transmission protocol, much like two modems try different coding schemes in order to set up a connection. A first contact handshake signal could be high intensity and simple to interpret, but it could describe a more efficient channel for further communication, that might for example use compression and maybe fainter or more subtle signals that wouldn’t be spotted as quickly by a general purpose SETI program.

  • Astronist October 9, 2015, 15:53

    Your post is based on the unspoken assumption that not a single civilisation embarks on interstellar expansion: all remain confined to their home planetary system, and probably their home planet. (Once the genie is out of the bottle within a planetary system, interstellar exploration is likely to follow as a matter of course.) Can you please explain your reasons for making this assumption?

    Stephen
    Oxford, UK

  • Brian McConnell October 9, 2015, 16:25

    @Chris

    The handshake analogy is a good one. There are lots of ways to balance ease of acquisition with data carrying capacity. You might, for example, have an always on pilot signal that carries no data, but is accompanied by side carriers that transmit data. The tradeoff is that higher speed equals less energy per bit transmitted, which means detection is harder. So a good strategy will be to have several carriers, some that are easy to acquire, but low bit rate, and some that are fast but will require larger telescopes to detect reliably.

    @Astronist

    In fact, if we travel to nearby solar systems, the first thing we will do is upgrade the Deep Space Network to provide long haul communication. So a system like this could be a heterogenous network of civilizations that developed independently, or it could be a network built by one or a few civilizations as they expanded.

  • Daniel Högberg October 9, 2015, 16:29

    Interesting concept! Finally a new way to think about why we have not yet been contacted, our nearest node have not found us yet or their first contact etempt is on its way to us right this moment :)

  • Daniel Högberg October 9, 2015, 16:33

    What are the potential number of solarsystems with confirmed planets in an 80 lightyear radius from us then?

  • Mike Lampton October 9, 2015, 16:34

    A common view among SETI researchers is that although ETI could be
    millions of years more advanced than Earth 2000, their physics and
    cosmology is identical to ours: limited to 3+1 spacetime, limited to
    lightspeed communications, and limited to sub-light travel.
    Yet, our Isaac Newtons and our Albert Einsteins have advanced
    our historical comprehension of our universe with astounding speed
    compared to cosmic time scales. Moreover, our present best “Lambda-CDM”
    model of the evolution of the universe suffers from bewildering
    inconsistencies. In a short writeup “Information-driven societies
    and Fermi’s paradox,” (IJA 13#4 2013), I point out that an improved
    understanding of the universe could resolve Fermi’s paradox and thereby
    open new avenues to SETI beyond probes, lasers, and radio.

  • Alex Tolley October 9, 2015, 17:25

    Given the latency due to node separation, would you expect redundancy be used rather than, or in addition to, retransmission of packets to ensure message reception was complete? If so, how might that be best carried out in a galaxy with random noise generating events? Redundancy first, then retransmission if message is incomplete?

  • Tom Mazanec October 9, 2015, 18:37

    As we progress to a Cloud using 5G communication, I would think a high data rate would be the defining characteristic of a galactic net . Maybe lasers are the equivalent of optic fibers in the infrastructure. Our First Contact message might be a design blueprint for a Neodymium or CO2 laser transmitter, and a Lincos type language to translate our culture into, so we can contribute to the Galactic Club.

  • jpg October 9, 2015, 21:07

    Ive often thought that a network would be based on extremely tight beams rather than omnidirectional broadcasts… Possibly laser or microwave beams. It would use less energy and be somewhat more “private”…
    Perhaps we should be looking for artifacts such as one would see with a light beam passing through a dusty room…
    Is it possible that light amplifier detectors could image a very fine line passing through intergalactic gas clouds? Or would background illumination completely swamp such a weak signal?

  • Brian McConnell October 9, 2015, 21:21

    @Alex redundancy in a packet switched network can be provided in a number of ways.

    The first and simplest is to retransmit packets periodically.

    Path redundancy is another. So if you want to make sure a packet gets to node #513 you can also send it to several peers that are at intermediate locations.

    Simple error detection algorithms like checksums will enable a recipient to detect damaged packets, and in some cases do brute force error correction. (The checksum is just an extra block of metadata so it does not obscure the payload).

    Simple error correcting codes, aka “majority vote” codes represent each bit of information as an odd number of bits. EG 1 is encoded as 111 and 0 as 000. So if one bit is flipped the original state is preserved.

    More sophisticated codes like Reed Solomon are even more robust as they can deal with burstl errors but are harder for a naive receiver to work out.

    So there are several ways to do this. The simplest is just to resend important packets repeatedly.

  • Harold Daughety October 9, 2015, 21:43

    This is all disturbingly similar in thought processes to the cargo cults of the Melanesian people, especially post WWII. We are discussing establishing contact with postulated advanced civilizations that can bestow great wealth (in the form of knowledge?) with no reason to believe such civilizations exist. There are elements of magical thinking in that and in terms of FTL travel and communications.
    Is this just a game? Is there one shred of science here?

  • Michael October 10, 2015, 1:40

    I suspect that these relays will be place at the gravitational focus points of their stars to reduce power requirements for incoming and out going information between stars. We may actually find a signal transmitting point some distance from a star when we find it.

    @Daniel Högberg

    ‘What are the potential number of solarsystems with confirmed planets in an 80 lightyear radius from us then?’

    This list is for 50 lyr’s

    https://en.wikipedia.org/wiki/List_of_nearest_terrestrial_exoplanet_candidates

  • John October 10, 2015, 8:08

    @Harold Daughety: The cargo cults had at least seen actual aircraft – we have never seen an ETI communication! However we know that civilisations as advanced as ours can exist, because, well, us. Such civilisations would derive benefit from contact with each other if it is possible. So, in general, while SETI is a longshot I’m a supporter. It’s the inverse of tracking asteroids in case they hit us: Tiny probability of s trike but the end of the world if we hit that ten million to one outlier event.

    With SETI it might be a ten million to one shot we actually find someone, but what it’s costing us vs the potential payoff of actually establishing 2 way contact with another civilisation makes it worht it. And, to be honest, for me having things like SETI makes life more fun an interesting!

  • Cambias October 10, 2015, 8:43

    Harold: by thinking about these issues we can do a better job of figuring out how to see if alien civilizations exist. We’re generating hypotheses to test. If you aren’t interested in SETI, nobody’s forcing you to care.

  • Matt October 10, 2015, 9:02

    Harold Daughety wrote:

    “This is all disturbingly similar in thought processes to the cargo cults of the Melanesian people, especially post WWII.”

    I don’t think this is like a cargo cult at all. The cargo cults did not understand the cultures they worshiped, but they at least had proof that they existed. We are speculating about behavior of ETIs without even having an existence proof. The cargo cults were better grounded than we are and their worship was more rational.

    I see the speculations about ET in Centauri Dreams and elsewhere as fiction, not science. This is more like a discussion of elements of some future science fiction novel than of life in the universe.

    I am a fan of packet switching networks and error detection algorithms. I hope an technological civilization we encounter will have better networking protocols and more sophisticated error detection algorithms.

    My expectation is that the hardest problem will be recognizing an extraterrestrial technological civilization for what they are. The range of possible solutions to technical problems is so wide that we should not expect an ETI to do anything as we do.

    None of this is to say that we should stop looking, or stop speculating. I do enjoy topics like this on Centauri Dreams.

  • Harold October 10, 2015, 9:59

    If redundancy is the objective, then adding a dedicated/AI controlled node would be orders of magnitude less expensive and risky than adding a civilization as a node. The only advantage of adding a civilization as a node would be any new information that civilization would add to the network. Imo, the information generated by a young civilization such as our own would become less unique, less valuable, the more connected we became to the “galactic club”. We may not be invited into the club until it becomes more work and more risky to keep us out of the club than inviting us in.

    It wouldn’t be that difficult to route around our solar system either. The tighter the transmission beams and the more efficient the compression, the easier it would be to keep us in the dark. There would be plenty of reasons to keep us out of the network as well. The information being transmitted could very well be digital copies of people.

  • David Joffe October 10, 2015, 13:29

    @Harold Daughety We have one important reason to believe other civilizations *may* exist: We know (‘for 100% fact’) that *our* civilization exists. If ours exists, it’s completely reasonable to hypothesize that others may exist* (it’s unscientific to assume one way or the other – so while we are in the realm of hypothesizing, there is nothing in the scientific literature so far that *proves* the existence of other civilizations to be impossible, and on the contrary, the huge magnitude of galaxies and planets and moons makes it seem statistically plausible, in fact likely, that others should exist). So the rest is simply firstly a matter of trying to estimate the approximately probability of other civilizations existing (for practical reasons), and then trying to determine how optimally to focus our efforts on detection, making contact, or other endeavors, e.g. travel. There is no magical thinking required. (Of course, we can retain some skepticism and postulate that we may be the only civilization in the universe, though if one understands the numbers, that idea seems vanishingly unlikely and almost bizarre.)

    * This is not the same as Russell’s teapot, because again, we know our civilization exists – here we are simply postulating the hypothetical existence of other instances of something we *know can exist*, i.e. a civilization. E.g. imagine a single-celled organism living in a puddle. There would be nothing unreasonable about such an organism postulating that perhaps other puddles may exist that also have single-celled organisms living in them, by simply extrapolating their own observations, even if they had not yet devised a way to prove or disprove the existence of other such puddles.

  • David Joffe October 10, 2015, 13:50

    @jpg “Ive often thought that a network would be based on extremely tight beams rather than omnidirectional broadcasts… Possibly laser or microwave beams. It would use less energy and be somewhat more “private”…”

    Hm, I think I agree, it seems likely to me that the majority of interstellar communications would probably be relatively directed, ‘tight’ beams, for the reasons you list. Though as with our own communication networks, there would probably be some mixture of both (e.g. on urban wireless networks you see a mixture of directed point-to-point nodes, as well as omnidirectional ‘access points’ that many clients can connect to – and the latter is also the model of an internal home or business wifi network). If we imagine a stage where, say, we had colonized nearly every corner of own solar system, it would probably be difficult to get away with not having at least some omnidirectional ‘access points’ – apart from there being thousands of potential (moving) bodies in the solar system at which humans may be present, there would also be communications requirements for those in mid-travel between bodies. So the major planets like Earth or Mars would probably serve as massive communications ‘hubs’. (Of course the movement of bodies isn’t per se a problem, as computer controls would simply keep them aligned – e.g. a Mars – Earths comms link could automatically algorithmically retain alignment – but this may be impractical if talking about thousands of potential client points.)

    The slow speed of light though might be an additional limiting factor to the *motivation* for creating massive amounts of interstellar communications infrastructure. Even if we extended human life to 10,000 years, it seems to me there would be relatively little motivation for the average individual on one planet to communicate with someone on another planet, say, 1000 light years away, or even 100 light years away .. perhaps I’m lacking imagination, but I assume it would probably be mainly limited to important stuff only (e.g. relating to survival, politics, war, colonization, travel). Interstellar political changes would play out slowly (though would remain important). You couldn’t really have ‘conversations’ with individuals that far away, and even following the news would be of limited interest, e.g. if you lived 1000 years from Earth, and (say) one country invaded another on Earth, by the time you even hear of it, 1000 years would have gone by. But on the other hand, if an alien race (say) invades Earth, then you do want to hear about it even if they’re 1000 years away, so you can start preparing in case they’re heading for you next. But I think my point was, there might not be all that much communications going on, so not picking up such communications doesn’t necessarily mean it’s not there – it might just not be that abundant.

  • Andrew Palfreyman October 10, 2015, 15:47

    This highly unlikely scenario would employ point to point links and thus our chances of discovering it are minuscule. Now multiply these two highly unlikely probabilities together, and there’s almost no meat on this bone.

  • Alex Tolley October 10, 2015, 17:51

    Somewhat tangential to this subject this item caught my eye. Physicists say energy can be teleported ‘without a limit of distance’

    If true, this could apply to communications too. However it caught my interest as it might be a good way to beam energy for propulsion. This is not unlike the approach Peter Watts’ describes for the deep space ship in Blindsight.

    More info here:
    http://www.tuhep.phys.tohoku.ac.jp/~hotta/extended-version-qet-review.pdf

    https://en.wikipedia.org/wiki/Quantum_energy_teleportation

    http://phys.org/news/2014-01-theory-teleport-energy-distances.html

    We’ll see if the idea pans out.

  • James Stilwell October 11, 2015, 11:39

    Sounds like a glalactic library–or encyclopedia–forming. Since large time gaps would exist between entries, 500 year old information some might find useful might be out of date…We need John Bell’s non-localism…

  • Harry R Ray October 11, 2015, 13:59

    Correct me if I am wrong: If such a network does exist, the NEAREST NODE must be farther than 40 light-years away, otherwise we would have gotten the message by now. The most recent posts on this website dealing with SETI have ALL focused on MINIMISING THE COST in some way or other, of sending signals! In my opinion, the CHEAPEST WAY TO DO THIS is “piggybacking’ on existing transmission. Case in point: If, in the future we use a phased array transmitting POWER BEAMS to lightsails, when the PROPER ALAIGNMENT occurs between us and a target planet, FOR ONE MINUTE ONLY, we could switch the frequency fron 68 gigahertz to a much lower ‘magic frequency” which would only affect the operation of the lightsail MINIMALLY!

  • Michael October 11, 2015, 14:50

    @Alex Tolley October 10, 2015 at 17:51

    ‘Somewhat tangential to this subject this item caught my eye. Physicists say energy can be teleported ‘without a limit of distance. If true, this could apply to communications too. However it caught my interest as it might be a good way to beam energy for propulsion. This is not unlike the approach Peter Watts’ describes for the deep space ship in Blindsight.’

    The idea is workable provided there is nothing else in the universe, I mean if the energy packet, matter or photon was entangled, which is possible and proven, the problem is what affects one affects the other. So if a beam is created the ‘other’ virtual beam must go in the other direction BUT it like the other beam can interact with material in its surroundings. How would you control what happens to the virtual beam? you would need to have a very long straight tube in a perfect vacuum to prevent any interactions which would affect the other beam. May be if two mirrored surfaces going in opposite directions were used so the beams reflected off each surface it could be done, not sure though.

  • Marshall Eubanks October 11, 2015, 18:32

    I think that a old-civilization galaxy would likely have something like this (to entities that live ~ 1 billion years, a 10^5 year message delay time would take up a proportional amount of time as a 3 day delay for a letter would to a human). Of course, I also suspect it would be done with neutrinos (which would be made possible by a mastery of condensed quark matter), so it would still take a while before we’ll be able to detect it, much less join in.

  • Mike October 11, 2015, 21:21

    Contact with other civilizations or at least intercepting communications with others would be monumental. It’d be nothing short of inspiring. Still unfathomable how a civilization could possibly communicate with others over such great distances and over such great time periods. But, given the use of “repeaters” and higher levels of understanding physics, anything is possible.

    Despite what people’s political views are, Snowden’s recent quib about us not being able to discern alien communication from natural backround noise was profound. Indeed other civilizations may communicate in encrypted data that we can’t even tell is deliberate communication. But, there are/will be civilizations that target earth with signals we can pick out.

  • PW October 12, 2015, 13:28

    SETI is worth the trouble and the expense and the wait.
    It’s cool that smart people keep thinking of new ways to pursue it. When the most obvious ploy fails, we try something else. I hope that continues, though I am not exactly holding my breath for the alien signal. The galaxy is just so huge, and old, and light propagates so slowly. I’m a bit discouraged by it, good thing others are less so.
    If we ever do hear something, we should just listen. And nothing more, for a long, long time. There is too much at stake.
    Meanwhile, it’s way more about what we do to reach out for ourselves. To find those other earths and know how far away they are. And look for ways to get ourselves there AND BACK and be able to provide continuing support and real time communication. The Mayflower colony would have been doomed without the ships coming back year after year.
    Otherwise, moving out of our solar system is a desperate, one way mission, highly likely to fail.
    I do support SETI and wish them all the best. I am not optimistic about waiting for a helpful message from the aliens as to how to proceed.

  • david lewis October 12, 2015, 20:08

    Unless there’s something beyond quantum computers, I can see such a network being useful for problem solving if nothing else, with a number civilizations opting to work together to solve the more intractable problems. Rather than energy usage, such as measured by the Kardashev scale, the level of problems solved by a civilization might be a more useful criteria by which to measure their status.

    As for actively searching for low-tech civilizations such as us, there would be no benefit to them. and I fail to see why they would bother unless it’s for altruistic reasons. We have “nothing” to offer them.

    I also doubt we would even be able to understand the information in such a network. It takes a brilliant mind now decades of study to be well versed in a single field; by the time a civilization is a million years old, with members who lived to be thousands of years, possessing IQs we can’t dream of, even if we lived to be a hundred we wouldn’t be able to comprehend what passes for pre-school for them.

    On the bright side, if such a network exists then when we can tap into it we could very well have access to the information billions of civilizations have gathered over billions of years. Sure, the nearest galaxies are millions of light years away, but such a network would be billions of years old and might very well have communicated with civilizations in galaxies tens of hundreds of millions of light years away.

  • Mark October 12, 2015, 20:10

    All technical discussion aside, we can be certain these networks exist and that they are very busy. Busy transmitting what? Encyclopedia Galactica? Blueprints for a FTL ship? Interdimensional Teleportation 101 lectures from the University of Kepler 438b?

    Of course, but mostly it’ll be pictures of aliens with their clothes off. Globally this is a $97 billion dollar industry. Extrapolate that out to potential inhabited worlds in the Milky Way galaxy alone and you’ll find your economic driver for this type of network.

  • ljk October 13, 2015, 9:36

    I will repeat this as many times as necessary: Stephen Hawking is no more an expert on alien intelligences than anyone else on Earth. His views in fact mirror the 1996 science fiction film Independence Day.

    I am not saying he is necessarily wrong, just that because these words emanate from him does not automatically make them golden and therefore right. What they do foster is a continued sense of antiquated fear about ETI which in turn could affect their study and search negatively – and please, folks, that 100 million dollars from the rich Russian guy is not going to last forever.

    Space.com adding to the pile here:

    http://www.space.com/30796-stephen-hawking-hostile-aliens.html

    My take in two parts here:

    https://www.centauri-dreams.org/?p=14703

    and here:

    https://www.centauri-dreams.org/?p=14754

  • Daniel Högberg October 13, 2015, 13:26

    I can not understand why an extraterrestrial civilization would want to travel many lightyears to kill us, when their space-technology that makes their trip to earth possible would be all they could ever need to survive, even without a planet..

  • Hiro October 13, 2015, 13:33

    @ ljk: it seems like Dr. Hawking just finished reading The Killing Star, hence he is afraid of “spending endless night in Central Park scenario” for the next several days before his fears disappear slowly over time.

    @ david lewis: Quantum CTC?

    http://arxiv.org/abs/1504.05911

    Of course, it’s more like extreme fiction than actual real science. Only “time” can tell whether it’s junk or useful in far future :)

  • ljk October 14, 2015, 9:19

    Daniel Högberg said on October 13, 2015 at 13:26:

    “I can not understand why an extraterrestrial civilization would want to travel many lightyears to kill us, when their space-technology that makes their trip to earth possible would be all they could ever need to survive, even without a planet.”

    Exactly. For example, in the 2011 SF film Battle: Los Angeles, the aliens were invading Earth for our… water.

    They could have chosen any number of much lower mass bodies in our outer Sol system if they wanted large quantities of that molecule, which – so far as we know – are also uninhabited, making ground troops and laser weapons unnecessary.

    Heck, they probably didn’t even need to leave their solar system unless they used up every last comet or ice moon, but then again they could have chosen from plenty of other systems which also have the same types of bodies. But no, let’s invade Earth with old fashioned military methods.

    https://www.youtube.com/watch?v=ORb3zC8z94w

    If an ETI does want to wipe us off the face of the planet (to make sure we are not some form of galactic competition or threat down the road), a few well aimed space rocks or a ship moving at relativistic speeds hitting Earth will do the trick and we will be defenseless against them.

  • Mark Zambelli October 14, 2015, 10:53

    I’ll echo ‘ljk’s comments in reference to ‘Daniel Högberg’s astute observation by also mentioning the film ‘Oblivion’… a film I really enjoy even with the glaring issue of needing our water. However, Hollywood et al. aren’t interested in the accuracy or especially the logic of a film; only that it makes the tills go ‘£-ker-ching-$’. We know this but we also appreciate that audiences absorb the ideas they see, even to the point of ‘learning’ their history, science, etc. Ask the lay-person about ‘Braveheart’ and you get their Hollywood-taught version and not the truth at all. What can we do against the onslaught of bad-science as it is fed to the masses? It’s a problem when the masses hold the key to the governments purse. So the consensus holds that ETIs are coming for our water, brains, bodies, oxygen, children… ad nauseum.

    There are good ‘alien’ movies out there but if they’re invading us forget it. It always seems like the moment they’d discovered ftl travel they had a whip-’round and destroyed all their ‘Logic for First-graders’ books before setting their sights on the human homeworld.

    Sometimes they get things right though. Speilbergs ‘ET’ involves a loveable stranded botanist (no, not Mark Watney!) and as ‘ljk’ correctly points out… lobbing rocks our way from afar is a really good tactic and was (close to accurately) portrayed in ‘Starship Troopers’ even though the rest was typical and suffered from being based on Heinleins fascist-anti-Chinese 50’s novel… and there’s the rub; we make up human-centric stories and transfer them to include ETI while making ETI play the role of our darker, human alter-egos… so the premise almost always fails.

    There are more good ones but Daniel Högberg was spot on in relation to the general invader scenario as it is portrayed. Good job there are places around to discuss more level-headed takes and ideas. None such a good place as here though ;)

  • Michael October 14, 2015, 14:06

    @ljk

    Daniel Högberg said on October 13, 2015 at 13:26:

    “I can not understand why an extraterrestrial civilization would want to travel many lightyears to kill us, when their space-technology that makes their trip to earth possible would be all they could ever need to survive, even without a planet.”

    Exactly. For example, in the 2011 SF film Battle: Los Angeles, the aliens were invading Earth for our… water.’

    They may have been after what is in the water, Deuterium, which makes a fine fusion fuel…tongue in cheek of course.

    They could have also worked out that we could be dangerous later on, I mean it may not be long before we make a breakthrough in physics that they have found out earlier that could influence an expansionism into space quickly. If for instance we find a neat way of manipulating the Higgs field and nullifying inertia we would be off to flying start. I would prefer it if we kept a low profile for now until we are more established in our solar system.

  • ljk October 14, 2015, 18:15

    Michael said on October 14, 2015 at 14:06:

    “I would prefer it if we kept a low profile for now until we are more established in our solar system.”

    That’s a bit of a sticky wicket. Not only have our electromagnetic signals created a sphere about 200 light years across (yes, I know most of them are weak but the military and planetary radars are strong, plus we have sent a few deliberate METI into the galaxy), but terrestrial life itself has a distinct biosignature. So while we could attempt to stop deliberate METI and tone down the general technological noise, Earth has numerous indications that it contains life for anyone smart and advanced enough to notice even from afar.

  • Harry R Ray October 19, 2015, 14:34

    Should we ACTUALLY FIND(WTF-001 anyone) a node, how do we log on? Some password ACCEPTABLE to all current participants that is being BROADCAST in a way not CONNECTED to the nodes themselves? Which brings up 187.5 and the FRB’s again. This was supposed to be a dead issue, with five new ones whose dispursion measures were not TIED to this number, but the paper HAS STILL NOT BEEN PUBLISHED! What, holding it up? Sould 187.5 hold up, I would find THAT a whole lot wierder than WTF-001’s unusual light curve. Turok et al are convinced that the universe is so SIMPLE that MOST (if not ALL) of its structural components can be described by just ONE number. Is 187.5 that number(pray that it is NOT 42-just kidding)?