[HN Gopher] Nuclear radiation used to transmit digital data wire...
       ___________________________________________________________________
        
       Nuclear radiation used to transmit digital data wirelessly
        
       Author : sizzle
       Score  : 88 points
       Date   : 2021-11-12 18:33 UTC (4 hours ago)
        
 (HTM) web link (www.lancaster.ac.uk)
 (TXT) w3m dump (www.lancaster.ac.uk)
        
       | Ekaros wrote:
       | Now I actually wonder how to do it over a wire. That is use
       | nuclear radiation to transfer data...
        
       | nukenuke wrote:
       | For those wondering, will not really work over long distances (>
       | 100 m) since fast neutrons will thermalize quickly in air and
       | other materials. This means they scatter around approaching a
       | random walk and lose energy, which makes the transmission beam
       | harder to detect.
       | 
       | This is really mostly feasible for ~single wall transmission.
        
         | mgsouth wrote:
         | How far can you go until the losses are over 160 dB? Reason I'm
         | asking is that LTE Cat-M (low-bandwidth IoT) go that low, or
         | lower [0]. GLONAS (GPS) receivers deal with over 180 dB of loss
         | [1]. It depends on the power level in the transmitter, and how
         | well the receiver can lock on to very faint, but expected,
         | patterns in the noise. One of the tricks is to re-transmit,
         | sometimes literally thousands of times.
         | 
         | [0] https://www.altair-semi.com/wp-
         | content/uploads/2017/02/Cover...
         | 
         | [1] https://en.wikipedia.org/wiki/DBm -- Satellites
         | transmitting +55 dBm, receivers seeing -127 dBm.
        
       | kazinator wrote:
       | That could be a fun activity for Boy Scouts; one boy, standing
       | outside of the concrete shed, is watching a geiger counter, and
       | the other sends Morse Code by moving a leaden lid up and down on
       | a sample of Plutonium.
        
         | laurent92 wrote:
         | There was a nuclear badge in the boys scouts, and one kid
         | actually got it, to the dismay of his mother.
         | 
         | More generally, had nuclear not been demonized as part of the
         | fear of mutual destruction ideology (I'm not saying it was
         | wrong), maybe we would have lived in a parallel world where
         | tinkering with radioactive elements would have been more
         | widespread, and innovation wouldn't have stalled for 60 years.
         | Maybe we'd have a lot of nuclear-in-a-box batteries by now.
        
         | aYsY4dDQ2NrcNzA wrote:
         | https://en.wikipedia.org/wiki/David_Hahn
        
       | orbital-decay wrote:
       | The paper is here:
       | https://www.sciencedirect.com/science/article/pii/S016890022...
       | 
       | Key takeaway here is novel fast neutron generators [1] that are
       | flat and electronically modulated, so they are potentially good
       | for data transmission through metallic vessels (ship hulls for
       | example) that doesn't require vessel penetration and isn't
       | heavily regulated like californium isotopes.
       | 
       | The researchers wanted to demonstrate the data transmission in
       | practice, but used a more conventional setup instead (a Cf-252
       | source mechanically modulated by a HDPE slab).
       | 
       | [1] https://ieeexplore.ieee.org/document/6275497
        
       | servytor wrote:
       | I was imagining a Monty Python scene where someone was using two
       | halves of lead, like coconuts, and slamming them repeatedly over
       | the radioactive material.
        
         | Arrath wrote:
         | Shades of the Demon Core.
        
           | _Microft wrote:
           | The Demon Core also came to my mind when reading GP's
           | comment. For those unaware, the Demon Core was a piece of
           | radioactive material and received its name after two people
           | died in different accidents while experimenting with it on
           | criticality .
           | 
           | https://en.wikipedia.org/wiki/Demon_core
        
       | danbruc wrote:
       | In case someone else is wondering, they modulated the neutron
       | beam by pneumatically moving a polyethylene block in front of the
       | Californium source which sits inside a one cubic meter water tank
       | and can be pneumatically moved close to one of the walls for
       | activation. The data rate was about one bit every ten seconds.
        
         | version_five wrote:
         | At this bitrate, and over short distances - maybe 1m, a
         | rotating permanent magnet (or a powerful electromagnet) could
         | also be competitive. It wouldn't work for anything with a high
         | magnetic permeability (like iron) but for non magnetic metal or
         | water a static field would penetrate at least a short distance,
         | enough to go through a wall.
         | 
         | (BTW, I've imagined that in the distant future, we'll have
         | gravity wave generators and detectors that don't have the same
         | constraints as EM based data transmissions. I don't know how
         | realistic this is.
        
           | fouronnes3 wrote:
           | Reminds me of that paper I read a long time ago, about how we
           | could detect advanced alien civilizations by analysing pulsar
           | signals. The hypothesis was that they would put massive
           | devices in orbit of pulsars to modulate their high energy
           | signals to use as ultra long range communication. Presumably
           | pulsars would be the only strong enough carrier wave.
        
         | titanomachy wrote:
         | I _was_ wondering, thank you! Surprised the article didn 't
         | bother with even a sentence to explain this.
        
           | op00to wrote:
           | I figured it was something like a trombone mute. Not sure why
           | that was the image I got of how they did it.
        
       | Trias11 wrote:
       | Newsomium decay causes Californium to be so radioactive
        
         | dang wrote:
         | Could you please stop posting unsubstantive and/or flamebait
         | comments? You've unfortunately been doing it repeatedly, and we
         | ban such accounts because we're trying for a different sort of
         | discussion here.
         | 
         | I don't want to ban you, so if you wouldn't mind reviewing
         | https://news.ycombinator.com/newsguidelines.html and taking the
         | intended spirit of the site more to heart, we'd be grateful.
        
       | bricss wrote:
       | 252G?
        
       | Cyder wrote:
       | neutrino messaging was mentioned in The Hummingbird Project...
       | Good movie
        
       | tantalor wrote:
       | It's a smoke signal.
        
       | jhallenworld wrote:
       | But won't the range be limited by neutron decay?
        
         | jjk166 wrote:
         | Thermal neutrons move at approximately 2000 m/s, with a half
         | life of about 612 seconds. Decay is a non issue but scattering
         | does put some limits (mean free path of a 14 MeV neutron in air
         | is about 140 meters), though if your goal is just to get a
         | signal through a wall you don't need particularly long range.
        
       | chaxor wrote:
       | As many have pointed out, this doesn't seem practically useful.
       | However, if you add an "i" and flip the "n" and "o" on that
       | messenger particle, I could see it being greatly useful.
       | 
       | Neutr _ino_ communications could travel into every nook and
       | cranny, very fast and far indeed.
        
         | folli wrote:
         | The radiation in the article is modulated by shielding and
         | deshielding the neutron source. How would you modulate a
         | neutrino?
        
           | jjk166 wrote:
           | Neutrino beams are produced by having a muons circulate in an
           | accelerator with long straight sections. As the muons decay,
           | they release neutrinos moving approximately in the same
           | direction the muon was. You modulate the neutrinos by
           | modulating the muon beam. The simplest way to do this is to
           | introduce or take away muons from the beam, but another
           | option is changing their energy. Muons have a half life of
           | approximately 2 microseconds in their inertial reference
           | frame, but from the standpoint of an observer, relativity can
           | make them seem to live much longer. Decrease the energy to
           | the beam energy such that they're moving slower and it is as
           | if their half life decreases, causing them to decay more
           | frequently and thus produce more neutrinos.
           | 
           | The real issue is the detection end. Because of how little
           | neutrinos interact with matter, you need a lot of neutrinos
           | to pass through a detector before you can expect to see a
           | signal, and then you need to distinguish that signal from
           | noise.
        
           | bally0241 wrote:
           | You don't modulate the neutrino beam itself, but you could
           | modulate the pion production beam. For typical neutrino beam
           | experiments this is done with a large magnetic horn which
           | focuses/defocuses (+/-) charged pions which then decay to
           | (anti)neutrinos and (anti)leptons. By changing the current in
           | the horn you could modulate the intensity of the beam to send
           | data.
           | 
           | Needless to say this is woefully impractical, would require
           | an extremely large neutrino flux and detector, and would have
           | an absolutely abysmal bit-rate. Not to mention you'd likely
           | only be able to send messages in one direction. But it could
           | be done.
           | 
           | see: https://www.fnal.gov/pub/today/archive/archive_2014/toda
           | y14-...
        
             | retzkek wrote:
             | It was actually demonstrated (over relatively short
             | distance) using the MINERvA detector at Fermilab:
             | https://arxiv.org/abs/1203.2847
        
           | therein wrote:
           | That's the question and precisely what would make it novel
           | and interesting.
           | 
           | If you can easily modulate the source of your signal as is
           | the case with the neutron source, it becomes as uninteresting
           | as morse code.
        
           | manpagereader wrote:
           | Why modulate it at all? Just use CW.
        
       | manpagereader wrote:
       | We used to do this by opening a port in the shield over an x-ray
       | source and detecting it with the predecessor of digital x-ray
       | sensors back in the lab, sending morse code.
        
       | yummypaint wrote:
       | Not great for long distances unfortunately, as your source will
       | always be isotropic. One could also do this with neutrons with
       | either 241am alphas on beryllium modulated electronically, or
       | with d2 beam incident on d2 target, or proton beam on a tritiated
       | titanium foil target. All should allow for faster modulation. The
       | beam based methods also allow for control of the outgoing energy.
        
         | gnufx wrote:
         | If you're allowed an accelerator, perhaps something like
         | https://en.wikipedia.org/wiki/ISIS_neutron_source if not in a
         | confined space.
        
         | trhway wrote:
         | >241am alphas on beryllium modulated electronically
         | 
         | sounds like a primitive logic gate to me :) One can imagine a
         | self powered logic circuits built along this way.
        
         | gh02t wrote:
         | I don't _want_ to hate on this research but my first thought
         | was  "well duh of course you COULD but why WOULD you?" This is
         | basically just Morse code with a neutron source. That this is
         | possible is obvious to anybody with a passing familiarity with
         | nuclear engineering, but equally clear is the lengthy list of
         | downsides. Just because nobody has done it doesn't make it
         | novel.
         | 
         | This is no doubt meant as a proof of concept and an
         | electronically controlled neutron generator would solve some of
         | the problems, but I still can't think of any use for this that
         | isn't better solved some other way.
        
           | bnegreve wrote:
           | > I still can't think of any use for this that isn't better
           | solved some other way.
           | 
           | What about this?
           | 
           | "In some safety-critical scenarios, such as concerning the
           | integrity of reactor containments, and metal vaults and
           | bulkheads in maritime structures, it can be important to
           | minimise the number of penetrations made through such metal
           | structures for communications cabling. The use of neutrons
           | for information transmission through such structures could
           | negate the need for such penetrations and is perhaps also
           | relevant to scenarios where limited transmissions are
           | desirable in difficult circumstances, such as for emergency
           | rescue operations."
        
             | smartscience wrote:
             | That's still more than a bit of a stretch considering the
             | drawbacks, such as making that vault or bulkhead material
             | radioactive even after the neutron beam has been shut off.
             | In practice the duraction of the induced radioactivity
             | varies considerably depending on the material; just hope
             | it's not an alloy that includes cobalt.
        
             | cycomanic wrote:
             | Well what about mechanical waves /sound waves. I mean we
             | are talking about rates of less than a bit per second. Just
             | have a small hammer ping your metal container. Will go much
             | further is much cheaper and can easily do a higher data
             | rate.
        
               | titanomachy wrote:
               | More moving parts than an electrically-modulated neutron
               | source. But this was my first thought as well.
        
         | sizzle wrote:
         | Great insight for us laymen. Curious, how are you so
         | knowledgeable about such an esoteric topic? are you a nuclear
         | physicist or...?
        
           | xattt wrote:
           | They have Q clearance(1), at least.
           | 
           | (1) https://news.ycombinator.com/item?id=29204027
        
       | awiesenhofer wrote:
       | I already have an existing IPoAC/RFC1149 connection, can I run
       | this one simultaneously or would it cause too many drops on the
       | old line?
        
       | kazinator wrote:
       | Speaking of mechanical devices to selectively obstruct radiation
       | ...
       | 
       | I had a manager who is a clever fellow. He used some construction
       | toy with electrical motor abilities to rig together a test
       | apparatus whereby a mobile device was placed into a steel cooking
       | skillet, and the apparatus was periodically lifting the lid.
       | 
       | This caused the device to go into and out of mobile coverage,
       | allowing for testing of in-and-out-of-coverage transitions, and
       | reproducing problems reported with respect to them.
        
       | jjcm wrote:
       | This seems like non-news? They're just using the amplitude of
       | neutron emission to encode data. This isn't unique at all to
       | radioactive decay - they're basically just using AM radio tech
       | over radioactive decay instead of radio waves. It doesn't provide
       | any benefits, it's more just a "neat!" thing.
        
       | rbanffy wrote:
       | In essence, they have invented the cellphone that actually causes
       | cancer ;-)
        
         | daniel-cussen wrote:
         | I've heard there's a lot of prior art.
        
           | rbanffy wrote:
           | Neutron bombardment is unhealthy, but it was never used for
           | communication until now.
        
             | daniel-cussen wrote:
             | I mean about a cell phone that causes cancer, it's too late
             | to patent that.
        
       | raldi wrote:
       | The article doesn't state what distance they were able to
       | transmit over.
        
         | java-man wrote:
         | During the Cold War, I've heard rumors of one directional
         | communication system with submarines using neutrinos.
         | 
         | I don't know what the utility of the system described in the
         | article though - neutrons will be absorbed pretty quickly, so
         | the communication must have a very short range.
        
           | perihelions wrote:
           | How could a _nuclear-powered_ submarine possibly host a
           | neutrino detector? You 're sitting meters away from one of
           | the brightest neutrino sources on the planet!
        
             | java-man wrote:
             | please see my comment below in this thread.
        
           | djsbs wrote:
           | "... using neutrinos"
           | 
           | "... neutrons will be absorbed..."
           | 
           | I made the same confusion for a second. Neutrons are easily
           | absorbed. Neutrinos (little neutrons) are almost impossible
           | to interact with (and therefore absorb)
        
           | ed wrote:
           | It takes something like 18 light years of lead to attenuate a
           | neutrino beam by half, so they'd need a pretty big receiver
           | :)
        
             | Accujack wrote:
             | It's possible to detect neutrinos with a scintillation
             | chamber, but in general only a tiny fraction of neutrinos
             | passing through would be observed. They really don't
             | interact with regular matter much.
             | 
             | However, it's the transmitter that would be nearly
             | impossible, because blocking neutrinos or affecting them in
             | such a way as to modulate the beam would be extremely
             | difficult.
             | 
             | I think we can probably rule out neutrino based
             | communications during the cold war, especially since VLF
             | did the job just fine.
        
               | jjk166 wrote:
               | Modulating neutrinos is easy. You just control the
               | production rate. For example ramping a fission reactor up
               | and down will create pulses of neutrinos (though it's not
               | terribly efficient). For practical neutrino
               | communications, you'd want to use a muon beam to generate
               | your neutrinos. The neutrinos are emitted roughly in the
               | same direction the muons were moving when they decay, so
               | you can make a directional beam, and by controlling the
               | number of muons decaying at any given point in time,
               | either by directly controlling the number of muons or how
               | much time dilation they experience in the beam, you can
               | ramp up and down neutrino production.
        
               | java-man wrote:
               | The "rumor" referred to an array of scintillators dragged
               | behid the submarine, with the ocean water as a detecting
               | medium. In theory, with clear enough water and large
               | enough detector volume, that idea might work. I vaguely
               | recall data rate of less than one bit per second.
        
               | ISL wrote:
               | The data-rate would be far below 1 bps. The event-rate in
               | SuperK [1] from the _Sun_ was ~0.1 /day/kiloton of water.
               | 
               | Signalling to submarines would require a Fermilab or
               | T2K-caliber accelerator with an ability to direct a beam,
               | with a properly-oriented pion-decay hall, generally in
               | the known direction of the submarine _and_ highly-
               | synchronized clocks (or a clever time-structure strategy)
               | to allow coincidence-detection for background-
               | suppression.
               | 
               | For scale, the MINOS detector [2] detected a couple
               | thousand events with a couple of years of beam-time.
               | 
               | [1] https://en.wikipedia.org/wiki/Super-
               | Kamiokande#/media/File:N...
               | 
               | [2] https://arxiv.org/pdf/1103.0340.pdf
        
               | extrapickles wrote:
               | That sounds a lot like the ELF radio system they used,
               | which basically was used to order submarines to surface
               | (or near enough) to receive new orders as the bandwidth
               | was <1 baud.
               | 
               | https://en.m.wikipedia.org/wiki/Extremely_low_frequency
        
         | bostonsre wrote:
         | Yea, I'm curious about this as well and what bit rate they were
         | able to achieve. Wondering if it could be used for high
         | frequency trading in the future since I would think neutrons
         | going straight from source to destination would be faster than
         | any other communication method (no idea if this would be too
         | dangerous or not tho).
        
           | djsbs wrote:
           | With neutrons, no. They're slow, isotropic and thermalize
           | easily.
           | 
           | With neutrinos that'd be a different story. They travel at
           | the speed of light (or just below it - depends who you ask)
           | and they aren't readily absorbed by anything. Therefore they
           | can travel through the earth instead of around it.
           | 
           | Problem?
           | 
           | Generation, modulation and detection of neutrinos.
        
             | gnufx wrote:
             | > They're slow, isotropic
             | 
             | Not necessarily, if produced with an accelerator.
             | (Potentially a nuisance to gamma-ray spectroscopists,
             | generating spurious anisotropic scattering peaks.)
             | Otherwise, yes.
        
           | darig wrote:
           | 1 bit every 10 seconds would never be used for HFT
        
           | [deleted]
        
           | sobellian wrote:
           | I would be very surprised if neutrons travel faster than a
           | microwave beam.
        
           | xvedejas wrote:
           | Radio waves already travel at the speed of light, I'm curious
           | what speed-up you're imagining? A shortcut through the earth
           | is the only option I can think of to beat radio's latency.
        
       | tyingq wrote:
       | 0.1 Baud? Hah!
        
         | dang wrote:
         | " _Please don 't post shallow dismissals, especially of other
         | people's work. A good critical comment teaches us something._"
         | 
         | https://news.ycombinator.com/newsguidelines.html
         | 
         | (We detached this subthread from
         | https://news.ycombinator.com/item?id=29203516.)
        
           | tyingq wrote:
           | Got it, though it wasn't meant as a dismissal...just
           | surprise.
        
         | [deleted]
        
         | GekkePrutser wrote:
         | It raises the question... Why? It's not practical and very
         | unwelcome for many obvious reasons. Like really in what
         | environment does it make sense to introduce radiation just for
         | the sake of data transfer?
        
           | pm90 wrote:
           | Just because it doesn't have any immediate applications right
           | now doesn't mean it won't in the future.
        
           | RosanaAnaDana wrote:
           | Space?
        
           | OldHand2018 wrote:
           | "In some safety-critical scenarios, such as concerning the
           | integrity of reactor containments, and metal vaults and
           | bulkheads in maritime structures, it can be important to
           | minimise the number of penetrations made through such metal
           | structures for communications cabling. The use of neutrons
           | for information transmission through such structures could
           | negate the need for such penetrations and is perhaps also
           | relevant to scenarios where limited transmissions are
           | desirable in difficult circumstances, such as for emergency
           | rescue operations."
        
             | ericpauley wrote:
             | I don't buy it. Clearly one has to run power to this
             | transmission device. Once you've drilled a single hole for
             | this all it takes is one tiny wire to vastly exceed the
             | data capacity of this system. You could probably even send
             | data at far higher bitrate over the existing power cable
             | itself.
        
               | jjk166 wrote:
               | You don't need to penetrate the wall if you have power
               | sources on both sides of the wall.
        
               | klyrs wrote:
               | Why is that obvious? Couldn't they use an RTG to power
               | the device without the need for a wire?
               | 
               | Though... it does seem like a piezoelectric transducer,
               | or even a relay, could transmit an audio signal through a
               | solid metal bulkhead much more efficiently.
        
             | djsbs wrote:
             | Use a magnet instead then. Flip it over with the pneumatic
             | arm.
        
           | 27182818284 wrote:
           | The first trans-atlantic telegraph message took 16 hours to
           | send.
        
           | pishpash wrote:
           | Probably military applications too if it evades conventional
           | detection.
        
           | sizzle wrote:
           | There can be many innovative use cases in industry or
           | military applications where wires cannot penetrate the
           | surface of an object and other signals are too weak to
           | penetrate the object to transmit data about something mission
           | critical.
           | 
           | This warrants future investigation at the very least, however
           | impractical it may be. Quantum computers may also benefit
           | from this technology, etc.
        
             | tyingq wrote:
             | It would be interesting to see what places some other
             | alternative like sound, light, laser, VLF, etc, aren't
             | viable options.
        
           | djsbs wrote:
           | You're basically right.
           | 
           | Miners trapped in a cave not penetrated by E&M waves?
           | 
           | Wont work.
           | 
           | Signal from inside a reactor?
           | 
           | No. No logic can modulate the signal in said reactor that
           | isn't destroyed by the radiation.
           | 
           | If you have a pneumatic arm to modulate this thing, use it to
           | flip a magnet. That'll better penetrate any shield than
           | neutrons.
        
             | jjk166 wrote:
             | Why wouldn't it work for the miners or the reactor?
             | 
             | Neutrons pass through rock quite well.
             | 
             | Reactors are basically just giant neutron transmitters, by
             | modulating reactor output you also modulate their neutron
             | output.
             | 
             | Flipping a magnet definitely won't penetrate a shield
             | better than neutrons, in fact because of Gauss' law it
             | probably won't penetrate at all.
        
           | londons_explore wrote:
           | I believe the theoretical throughput of a modulated neutrons
           | is _very_ _very_ high - substantially higher than the
           | electromagnetic waves we send today.
           | 
           | Given that, perhaps the people of 1000 years from now will be
           | using them to do data transfer because electromagnetic waves
           | are far too primitive and low bandwidth.
        
             | gnufx wrote:
             | On the basis of what physics?
        
         | jfoutz wrote:
         | I like to point at the signal fire in lord of the rings.
         | Absurdly elaborate communication system that can only one shot
         | a single bit. But it's far far faster than any alternative. And
         | if both sides understand the meaning of the message, it could
         | be worth it.
         | 
         | I could see a regular pulse being a useful monitoring system
         | for (whatever they care about). no pulse, send help.
        
           | jjk166 wrote:
           | Although the beacon system (technically a form of semaphore)
           | could likely have been much better optimized.
           | 
           | For example, if a single pyre went unattended or was
           | otherwise unable to light their fire (for example say an orc
           | band attacked it), the whole system would fail, and there
           | would be no way of knowing that it had failed. Consider also
           | the possibility that one of the teams may have been able to
           | light their fire, but for fear of drawing enemy attention to
           | themselves, choose not to. Same effect. A more failsafe
           | option would be to have the fires constantly burning with the
           | light being cut off as the signal bit. This could be
           | accomplished quickly and easily by having some shutter that
           | drops down and blocks the fire's light. If one of the
           | stations were abandoned or damaged, its fire would go out,
           | alerting the network that something was amiss. This also
           | means that the cowards who don't want to alert orcs to their
           | position need only stop tending their station when in danger,
           | and they are free to flee.
           | 
           | Of course once you have some shutter in place to quickly
           | block out light, you can presumably raise and lower the
           | shutter. With an appropriate protocol, you can essentially
           | achieve a visual telegraph. If each station maintains two
           | fires, you can achieve bi-directional communication. This is
           | also good for eliminating false positives for the main alert
           | function if one fire just goes out for some reason.
           | 
           | It's interesting that real life semaphore systems like
           | Phryctoria or the Byzantine Beacons did not implement fail-
           | safe methods.
        
           | spoonjim wrote:
           | You don't have to use a fictional example of a signal fire...
           | it was used in ancient China to send exactly this message:
           | "Send the army"
        
       | FredPret wrote:
       | This is probably the tech that drives the Pip-Boy
        
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       (page generated 2021-11-12 23:00 UTC)