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Lack of technological progress

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Comments

  • #92
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    I have a question about radio/laser signals that the new search for alien life project is meant to uncover. Would it be possible if we did find an alien signal, to decode it? I mean in the sense of say we find a radio signal, would we be able to recompile it and watch alien tv? In other words a window onto a distant world?


  • #93
    Tenshot
    Registered Users Posts: 648 ✭✭✭Tenshot


    Only reading this thread now. WaitButWhy has some great recent articles on several of the topics mentioned earlier:
    They're all long reads (the SpaceX/Mars one is very long) but well written, entertaining, and definitely worth the time of anyone following this discussion.


  • #94
    Sam Russell
    Moderators, Science, Health & Environment Moderators Posts: 19,336 Mod ✭✭✭✭Sam Russell


    nyarlothothep wrote: »
    I have a question about radio/laser signals that the new search for alien life project is meant to uncover. Would it be possible if we did find an alien signal, to decode it? I mean in the sense of say we find a radio signal, would we be able to recompile it and watch alien tv? In other words a window onto a distant world?

    Think of it the other way.

    For alien intelligence to receive our 'intelligent' radio transmissions, they would be unable to receive them for a while because we have only discovered radio recently (well in cosmic terms). That is, they would need to be nearer than 100 light years.

    For intelligent alien life forms to exist currently, and within communicable distance, and be of a mind to be bothered communicating, well that would indeed be an unlikely event.

    I do not think it is likely at all.


  • #95
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    Sam Russell wrote: »
    Think of it the other way.

    For alien intelligence to receive our 'intelligent' radio transmissions, they would be unable to receive them for a while because we have only discovered radio recently (well in cosmic terms). That is, they would need to be nearer than 100 light years.

    For intelligent alien life forms to exist currently, and within communicable distance, and be of a mind to be bothered communicating, well that would indeed be an unlikely event.

    I do not think it is likely at all.

    But would it be possible to reconstruct a 1000 year old alien tv signal for example? I'm not talking about communication, just knowledge of another civilisation.


  • #96
    Sam Russell
    Moderators, Science, Health & Environment Moderators Posts: 19,336 Mod ✭✭✭✭Sam Russell


    nyarlothothep wrote: »
    But would it be possible to reconstruct a 1000 year old alien tv signal for example? I'm not talking about communication, just knowledge of another civilisation.

    It is hard enough receiving a signal from Divis at a distance of 100 km, so what chance at a few light years? I doubt that intelligent life forms would watch TV anyway.


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  • #97
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    Sam Russell wrote: »
    It is hard enough receiving a signal from Divis at a distance of 100 km, so what chance at a few light years? I doubt that intelligent life forms would watch TV anyway.

    Why did we send out that message to Alpha Centauri if the signal is going to be so degraded? Would laser communication experience similar signal degradation problems? I would hold the other view, that there is probably more than likely some sort of convergence with intelligent life and imaginative worlds/communication through audiovisual means would be expected.


  • #98
    Sam Russell
    Moderators, Science, Health & Environment Moderators Posts: 19,336 Mod ✭✭✭✭Sam Russell


    nyarlothothep wrote: »
    Why did we send out that message to Alpha Centauri if the signal is going to be so degraded? Would laser communication experience similar signal degradation problems? I would hold the other view, that there is probably more than likely some sort of convergence with intelligent life and imaginative worlds/communication through audiovisual means would be expected.

    Look at the speed our communication technology has moved in the last 150 years out of the last 150 million years. We have moved from horse drawn carriages to rocket ships, from semaphore flags to fibre based gigabits/s digital communications. Is it likely that alien civilisations would be at the exact level of development that we are at? Then take into account the distance and time taken to communicate. Whether they are there or not does not matter because we will never meet or greet them.


  • #99
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,656 Mod ✭✭✭✭Capt'n Midnight


    nyarlothothep wrote: »
    I have a question about radio/laser signals that the new search for alien life project is meant to uncover. Would it be possible if we did find an alien signal, to decode it? I mean in the sense of say we find a radio signal, would we be able to recompile it and watch alien tv? In other words a window onto a distant world?
    Probably not.

    First of all there's the digital cliff. With analog signals TV signals for example even if the reception is poor you could pick up fuzzy monochrome pictures or fuzzy sound. ET might take a while to figure out NICAD stereo or the colour, but video is very easy to figure out what with all the synch pulses to tell you when to start a new line or new picture regardless of which PAL / NTSC / SECAM you use.


    For digital even if you know how to detect and demodulate the signal and know which error correction to use all you'll end up is a stream of data. BTW US, Japan, and the rest of the world use totally incompatible systems. ( technically we use somethYou'd still have to decode the compressed stream then extract the data, and good luck if it's encrypted. Power is is vastly reduced compared to analog systems.

    And then there's frequency reuse, Saorsat uses a spot beam and you can pick it up all over Ireland. Go to Wales and apart from the very western extremities you won't pick up anything due to interference from a spot beam for France.


  • #100
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    Capt'n Midnight wrote: »
    Probably not.

    First of all there's the digital cliff. With analog signals TV signals for example even if the reception is poor you could pick up fuzzy monochrome pictures or fuzzy sound. ET might take a while to figure out NICAD stereo or the colour, but video is very easy to figure out what with all the synch pulses to tell you when to start a new line or new picture regardless of which PAL / NTSC / SECAM you use.


    For digital even if you know how to detect and demodulate the signal and know which error correction to use all you'll end up is a stream of data. BTW US, Japan, and the rest of the world use totally incompatible systems. ( technically we use somethYou'd still have to decode the compressed stream then extract the data, and good luck if it's encrypted. Power is is vastly reduced compared to analog systems.

    And then there's frequency reuse, Saorsat uses a spot beam and you can pick it up all over Ireland. Go to Wales and apart from the very western extremities you won't pick up anything due to interference from a spot beam for France.

    So if you picked up an alien analogue signal it might be possible to decode it but not likely if there was interference from other sources? What's the point of SETI or that new project funded by the Russian dude if the signals get scrambled?


  • #101
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,656 Mod ✭✭✭✭Capt'n Midnight


    nyarlothothep wrote: »
    So if you picked up an alien analogue signal it might be possible to decode it but not likely if there was interference from other sources? What's the point of SETI or that new project funded by the Russian dude if the signals get scrambled?
    It's just to pick up new signals.

    For example we are chucking out lots of power on 50Hz and 60 Hz mains, and radar. No information carried but would stick out on a frequency analyser. Analog radio is being phased out, so just the FM stations left. DAB uses lower power.

    Dispersion is another effect that will smear out the information in a signal.

    If you set up a licensed radio link here you aren't allowed more excess power than necessary to get through rain fade. The days when people could pickup Band I BBC TV in South Africa are long gone.


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  • #102
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    Capt'n Midnight wrote: »
    It's just to pick up new signals.

    For example we are chucking out lots of power on 50Hz and 60 Hz mains, and radar. No information carried but would stick out on a frequency analyser. Analog radio is being phased out, so just the FM stations left. DAB uses lower power.

    Dispersion is another effect that will smear out the information in a signal.

    If you set up a licensed radio link here you aren't allowed more excess power than necessary to get through rain fade. The days when people could pickup Band I BBC TV in South Africa are long gone.

    What about laser signals? Would it be possible to decrypt those? Would they suffer signal degradation?


  • #103
    Sam Russell
    Moderators, Science, Health & Environment Moderators Posts: 19,336 Mod ✭✭✭✭Sam Russell


    nyarlothothep wrote: »
    What about laser signals? Would it be possible to decrypt those? Would they suffer signal degradation?

    Lasers have a very small cross section so there is little chance of intercepting any laser beam unless it is aimed at us, and I mean by us - at a particular individual. Pilots complain of lasers being aimed at them coming into land. Lasers are that specific.

    No chance of detecting an alien laser.


  • #104
    nyarlothothep
    Registered Users Posts: 5,176 ✭✭✭nyarlothothep


    Sam Russell wrote: »
    Lasers have a very small cross section so there is little chance of intercepting any laser beam unless it is aimed at us, and I mean by us - at a particular individual. Pilots complain of lasers being aimed at them coming into land. Lasers are that specific.

    No chance of detecting an alien laser.

    Irc that Russian oligarch backed program has included lasers in the search.


  • #105
    Maximus Alexander
    Registered Users Posts: 13,080 ✭✭✭✭Maximus Alexander


    lazybones32 wrote: »
    People seem more preoccupied with *insert triviality here* than with a human setting foot on our nearest Planet.

    I don't think the image of a pioneering astronaut being simultaneously crushed and boiled alive is all that trivial. :pac:


  • #106
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 90,656 Mod ✭✭✭✭Capt'n Midnight


    Maximus Alexander wrote: »
    I don't think the image of a pioneering astronaut being simultaneously crushed and boiled alive is all that trivial. :pac:
    Don't forget they'll also be poisoned, asphyxiated, corroded and baked while that's going on too.

    And possibly tin plated with tellurium.


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