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ET Will Phone Home Using Neutrinos, Not Photons

Posted by timothy on from the speak-and-spell-is-cross-particle-compatible dept.

KentuckyFC writes "Neutrinos are better than photons for communicating across the galaxy. That's the conclusion of a group of US astronomers who say that the galaxy is filled with photons that make communications channels noisy whereas neutrino comms would be relatively noise free. Photons are also easily scattered and the centre of the galaxy blocks them entirely. That means any civilisation advanced enough to have started to colonise the galaxy would have to rely on neutrino communications. And the astronomers reckon that the next generation of neutrino detectors should be sensitive enough to pick up ET's chatter."

18 of 299 comments (clear)

  1. Still bound by the speed of light by Lord+Byron+II · · Score: 4, Insightful

    Any civilization that wants to communicate across the galaxy is going to use something (and I don't know what that something would be) other than a particle that can't travel faster than light. The Milky Way is about 100,000ly across, so the ping times from one side to the other would be 200,000 years - try playing Intergalactic Counter Strike over that.

    Neutrinos might be good for short distances (100ly), but then, you're less likely to encounter interference sources. Since photons are easier to emit and detect, they are the more likely choice.

    In summary: photons for short distances, since interference isn't a factor and nothing for long distances since lag time makes meaningful communication impossible.

    1. Re:Still bound by the speed of light by Anonymous Coward · · Score: 1, Insightful

      I supposed you believe Star Trek is a documentary.

    2. Re:Still bound by the speed of light by Thanshin · · Score: 5, Insightful

      The Milky Way is about 100,000ly across, so the ping times from one side to the other would be 200,000 years - try playing Intergalactic Counter Strike over that. You're assuming a being that senses time as we do. An alien creature might live for millions of years and generate the simplest thought in years. two hundred thousand years might be a blink, for them.

      The time from big bang to big crunch might be a "day" for them. Our entire civilization would be like a lightning flash. They'd consider carbon based civilizations as random events that cover entire galaxies in an instant and then fade to void by the next.

      If that's the case, I don't think we'd be much interested in their messages, though.
    3. Re:Still bound by the speed of light by sysusr · · Score: 5, Insightful

      The time from big bang to big crunch might be a "day" for them. Our entire civilization would be like a lightning flash. Are you suggesting some sort of hyper-slow motion state (metabolism, perception etc)? If so, that would be an extreme natural disadvantage. They wouldn't even be able to keep up with the geological events on their home planet, let alone adapt to predators.

      Such a species cannot survive. Even a lack of natural predators wouldn't help: geologically active planets would take care of them.

      "Nature always finds a way."
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      \x72\x6D\x20\x2D\x72\x66
    4. Re:Still bound by the speed of light by Thanshin · · Score: 4, Insightful

      Such a species cannot survive. Even a lack of natural predators wouldn't help: geologically active planets would take care of them. Such a species could be "big" enough as to not be affected by such measly matters.

      Such a species might live and sense the universe in several more dimensions than us. A single galaxy in a single three dimensional volume might be the smallest of it's body "cells".

      Planetary geological activity would bother them about as much as quark behavior bothers us. i.e.: They'd need much advancement to even be able to detect it.
    5. Re:Still bound by the speed of light by Lord+Byron+II · · Score: 2, Insightful

      With a 200ly lag, you could still hold a meaningful conversation. You might not be able to play CS, but you could transmit the works of Shakespeare and have them get there before your species is long extinct.

    6. Re:Still bound by the speed of light by Anonymous Coward · · Score: 1, Insightful

      Quantum Entanglement does not transmit information faster than light.

      Apparently, it does. Oh no it doesn't. The measurement of angular momentum at one position causes a state vector reduction which also applies (immediately) to the other photon, but this effect cannot be used to transmit information faster than light.

    7. Re:Still bound by the speed of light by Anonymous Coward · · Score: 1, Insightful

      No, thats absolutely wrong.

      It is not accurate to say that each particle has read the same (cough hidden) variable in some higher dimension. Bell ruled that out with a crafty little thought experiment which was ultimated proved legit by Aspect et. al.

      His whole arugment is putting in whatever hidden variable might be there and then showing that any hidden variable, whatever its presentation, simply by its presence, alters the result of ANY experiment in a way that QM immediately refutes.

      QM is complete in that respect, which was all the more disconcerting.

      Shit is non-local. You don't break the 'link' between two entangled particles because even thinking of them as two seperable things is wrong,

  2. What about those from the sun? by molo · · Score: 5, Insightful

    I thought there were billions of neutrinos coming from the Sun every second. Wouldn't that provide a lot of noise to drown out your signal?

    -molo

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    1. Re:What about those from the sun? by MobyDisk · · Score: 4, Insightful

      There's also billions of photons coming out of the Sun every second. Yet we still use light to communicate.

    2. Re:What about those from the sun? by HeroreV · · Score: 2, Insightful

      Light can be blocked quite easily. That's what makes it useful for communication. Radio communication would be overcome with noise if every signal transmitted could shoot right through the entire universe with no problem. We rely on being able to use the same wavelength and frequency for communication in different areas. We rely on distant signals being blocked and filtered away.

  3. Faster than light? No? Useless? by JSBiff · · Score: 3, Insightful

    Correct me if I'm wrong here, but communication with neutrinos would still NOT be faster than light, right? I'm sorry, but I don't think any galaxy-spanning civilization can possibly exist without FTL communication. Like, thousands of times FTL, because of the massive distances involved. According to one site the Milky Way is about 90,000 light years across. Which means it would take, let's see, 90,000 years (hard math, there) for a signal to cross the galaxy. Not exactly useful for galactic communications.

    This is also why I think projects like SETI@Home are ridiculously stupid. Even if other intelligent life did evolve elsewhere in the galaxy or universe, unless they evolved sooner than us (by at least the amount of time it would take for signals to travel from their world(s) ) their signals likely wouldn't have reached us yet. It's also possible that they evolved, developed RF technology, then either died out (and so stopped sending coherent signals), or moved on to FTL comms that we currently have no idea how to receive, or even the basic principles that they are based on (since we currently have no notion of any possible way for information to travel faster than the speed of light).

    Since we've only been receiving RF signals for about 100 years, the window of opportunity for other civilizations' RF signals to reach us during the period in which we were 'listening' is ridiculously small.

    Neutrino comms might be good for communicating inside of our Solar system, but unless they travel FTL, it would take a message a little over 4 years just to reach the next closest star to our Solar system. That seems pretty useless to me.

  4. Nuttier than fruitcakes by Ancient_Hacker · · Score: 1, Insightful

    Big problem, you can't aim, focus, or do anything other with neutrinos than create them.

    That means that 99.9999% of all neutrinos ever created are still zoooming around the universe.

    And there are a billion billion stars all making 10^37 neutrinos every second.

    That's what's called "background noise".

    Now there are several noise-reduction strategies, like narrow filters (which don't work well when the endpoints are moving). But still, it's hard to make a signal make a dent with all that background noise.

    1. Re:Nuttier than fruitcakes by pla · · Score: 2, Insightful

      Big problem, you can't aim, focus, or do anything other with neutrinos than create them.

      ...Yet. Since they do interact with ordinary matter to some degree, we can reasonably expect to some day have the ability to make/use/detect them in a controlled and predictable manner.



      Now there are several noise-reduction strategies, like narrow filters (which don't work well when the endpoints are moving). But still, it's hard to make a signal make a dent with all that background noise.

      Now apply the same reasoning to photons... Have you any idea just how many of them come at us from every direction, constantly, even during the night in a "dark" room? Fortunately, we can select them based on direction, frequency, amplitude, phase, polarization, and probably a few more properties that I can't think of at the moment. Why would we expect neutrinos to have any fewer selectable properties on which to filter? In fact, they would likely have more aspects to select for, as they periodically convert between several different flavors.

    2. Re:Nuttier than fruitcakes by pla · · Score: 1, Insightful

      Perhaps you don't understand anything about neutrinos.

      Perhaps not. Or, perhaps I did my dissertation on flavour changing transformations while studying under Glashow at BU while you still wore diapers[*]. Amazing thing about the internet, you never to whom you might find yourself talking - only what they have to say.



      They don't respond to electromagnetism, gravity, or the strong force. That means it's really hard to get a hold of them, like impossible.

      ...And yet, neutrons still decay to protons via emission of a W-boson. Funny, that.



      * I didn't. Just sayin'.

  5. Speed of Light != Useless by LakeSolon · · Score: 5, Insightful

    There are alot of posts saying "Well it's still not faster than the speed of light, so it's still useless for a pan-galactic civilization".

    If your two options are: A) communicate at the speed of light, or B) don't communicate...

    I think it's reasonable to assume you'd find some communication, no matter how slow, useful.

    We've gotten so accustomed to (what is to our senses) instantaneous communication it's easy to forget that empires existed across much of our globe when the fastest method of communication was a sailing ship.

    We've seen our 'world' shrink a great deal in the past few hundred years. Is it so hard to imagine it growing again?

  6. Neutrinos are HARD to detect by AceJohnny · · Score: 2, Insightful

    Oh yeah sure, let's use neutrinos, who's most remarkable physical property is that they barely interact with matter, no problem!

    Alien tech indeed...

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  7. Re:Why communicate at all? by Creepy+Crawler · · Score: 2, Insightful

    Not really..

    If we can learn the nanotech and computing required, we should be able to upload ourselves in durable substrate (diamondoid CPUs). Once we have control what was once only biological control, we could change the way we perceive time to say a second per year (or more or less for the required job).

    It could also be said that if we lived between compute platforms in each solar system, our global consciousness could be diffuse and communicate with the idea that light speed is the barrier which we will never cross.

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