back to article Boffins have fabricated microscopic sci-fi tractor beams for real

The idea of tractor beams, concentrated rays of energy used to trap and move objects at a distance, was first introduced in science fiction. A group of physicists from the University of Adelaide, Australia, and the Université de Limoges, France, however are trying to make them a reality. But don’t get too excited, current …

  1. Anonymous Coward
    Anonymous Coward

    diverse new possibilities

    atomic snooker table!

    1. Michael H.F. Wilkinson Silver badge
      Happy

      Re: diverse new possibilities

      Good idea. Must be a lot safer than intergalactic bar billiards, which can get planets potted strait into black holes

    2. Lord Elpuss Silver badge

      Re: diverse new possibilities

      IBM Atoms

      And that was back in 1989.

      1. Spherical Cow Bronze badge

        Re: diverse new possibilities

        The Acorn Atom predated the IBM Atoms by seven years ;-)

        https://en.m.wikipedia.org/wiki/Acorn_Atom

    3. Compliant Andy

      Re: diverse new possibilities

      They call me Dave 'cinzano bianco' Lister, cos once i'm on the table you can't get me off!

    4. Anonymous Coward
      Anonymous Coward

      Re: diverse new possibilities

      >atomic snooker table!

      I was thinking more cheating at snooker if it's invisible.

  2. Terje

    So what am I missing here, what's the difference to an optical tweezer?

    1. Wellyboot Silver badge

      @Terje - This one has better PR & special effects.

  3. Anonymous Coward
    Anonymous Coward

    the description makes it sound more like a vaccuum cleaner than a tractor beam. whatamimissinghere?

    1. Mark 85 Silver badge
      Paris Hilton

      One sucks, the other just seems to hold things in place and can move them back and forth, apparently. Maybe we need to consult Paris?

      1. Anonymous Coward
        Anonymous Coward

        I'm sure they can be combined, I'm almost certain I have seen Paris applying both together.

  4. Anonymous Coward
    Anonymous Coward

    using beams of light to manipulate atoms.

    This was the bit where my brain hit a stop sign. Aren't photons massless ?

    1. Terje

      Re: using beams of light to manipulate atoms.

      Photons are massless, but they have momentum. If you are looking towards the sun you are actually experiencing being pushed backwards by the sunlight, be it very very very weakly.

      1. disgustedoftunbridgewells Silver badge

        Re: using beams of light to manipulate atoms.

        But ( and I know I'm wrong about this, but that doesn't mean I understand ), if they're massless then the force they exert is their speed multiplied by zero?

        1. Loyal Commenter Silver badge

          Re: using beams of light to manipulate atoms.

          But ( and I know I'm wrong about this, but that doesn't mean I understand ), if they're massless then the force they exert is their speed multiplied by zero?

          Newtonian mechanics (F=mv) applies pretty well at non-relativistic speeds (i.e. anything travelling at under an appreciable fraction of the speed of light). Photons travel at the speed of light (in a vacuum, anyway), so Einstein's pesky general realtivity comes into effect, and those equations get a whole load more terms in them.

          1. Loyal Commenter Silver badge

            Re: using beams of light to manipulate atoms.

            ...and I don't know who down-voted the OP. For someone not versed in relativistic mechanics, it was a perfectly reasonable question. It seems a bit off to down-vote someone for wanting to learn.

          2. AceRimmer1980
            Coat

            Re: using beams of light to manipulate atoms.

            would you need Newtonian mechanics to service your tractor beam?

            1. Rich 11 Silver badge

              Re: using beams of light to manipulate atoms.

              would you need Newtonian mechanics to service your tractor beam?

              No, quantum mechanics, but the problem with them is that you can never quite be sure whether they turned up.

              1. DougS Silver badge

                Re: using beams of light to manipulate atoms.

                And when quantum mechanics finish their service and send you the bill, any attempt to read the amount on the bill in order to write the check will change the amount.

                If you have them auto deduct from your account, then the time they remove the money might be before you call for service, but you can prevent that by checking your account regularly.

                1. ibmalone Silver badge
                  Boffin

                  Re: using beams of light to manipulate atoms.

                  If you have them auto deduct from your account, then the time they remove the money might be before you call for service, but you can prevent that by checking your account regularly.

                  Upvote for referencing one of the lesser known complementary pairs.

              2. Red Bren

                Re: using beams of light to manipulate atoms.

                "No, quantum mechanics, but the problem with them is that you can never quite be sure whether they turned up"

                You can know when they turn up or where they turn up, but not both.

        2. eldakka Silver badge
          Boffin

          Re: using beams of light to manipulate atoms.

          But ( and I know I'm wrong about this, but that doesn't mean I understand ), if they're massless then the force they exert is their speed multiplied by zero?

          Only if you use the 'reduced' version of the energy formula, E=mc^2.

          The 'strict' formula from wikipedia is

          E=sqrt( (mc^2)^2+(pc)^2 )

          Here the (pc)^2 term represents the square of the Euclidean norm (total vector length) of the various momentum vectors in the system, which reduces to the square of the simple momentum magnitude, if only a single particle is considered. This equation reduces to E = mc^2 when the momentum term is zero. For photons where m=0, the equation reduces to E=pc.

          and also:

          The energy for photons is E = hf, where h is Planck's constant and f is the photon frequency. This frequency and thus the relativistic energy are frame-dependent.

      2. Rich 11 Silver badge

        Re: using beams of light to manipulate atoms.

        If you are looking towards the sun you are actually experiencing being pushed backwards by the sunlight, be it very very very weakly.

        Though that force always feels a damn sight stronger if you're hungover.

      3. The Oncoming Scorn Silver badge
        Coat

        Re: using beams of light to manipulate atoms.

        ....& there was I thinking I was staggering backwards due to the sudden exposure of bright natural sunlight after leaving my windowless Mission Control at 5pm.

        Getting me coat cause the white shit is forever getting closer to falling down at this time of year.

      4. bombastic bob Silver badge
        Boffin

        Re: using beams of light to manipulate atoms.

        right, with momentum and velocity = speed of light, you can calculate an effective mass or 'rest mass' using the e = m * c^2 formula when the energy of the photon [related to frequency] is known

        photons are like a 5th state of matter, one step beyond plasma, matter converted into pure energy. a 6th state would be the 'atomic particle mush' you'd find within a black hole

    2. Francis Boyle Silver badge

      Re: using beams of light to manipulate atoms.

      Not massless — they simply lack rest mass. Plenty of relativistic mass there though.

  5. Anonymous Coward
    Anonymous Coward

    Photons are massless, but they have momentum

    In which case, why do people doubt the em-drive ?

    (You can tell my particle physics is a bit 1st grade ...)

    1. Paul Crawford Silver badge

      Re: Photons are massless, but they have momentum

      The thing about the em-drive is that the photons/EM waves are internal, so if (and its a big 'if') it works then it is defying the normal requirement for momentum transfer outside of the spacecraft, etc.

      But you can use a light/heat source or radio to act as a (very weak) drive since the emission of radiation has a momentum transfer effect as it propagates away.

      Edited to add: Seems the commentards further down the page have already answered as such!

    2. The Oncoming Scorn Silver badge
      Alien

      Re: Photons are massless, but they have momentum

      I saw this documentary...

      http://www.fanderson.org.uk/epguides/tdateg.html

      Brian "Gordons Alive!" Blessed in it so it must be true.

  6. Terje

    The problem was not that an em drive don't work, if you shine a flashlight backwards you will accelerate forwards, it's just that the effect is so incredibly small as to be pointless, the em-drive claimed to generate way to much thrust.

    1. John Mangan

      Em Drive

      I think the perceived problem with the em Drive was that the photons bounced back and forth within a chamber but apparently produced motion in one direction which looks like momentum isn't being conserved. People get itchy about things like that.

      1. Terje

        Re: Em Drive

        I have to admit that I never looked to carefully at the proposed em drive, but I do recall some chamber that somehow amplified things in ways that should not be possible.

        1. Anonymous Coward
          Anonymous Coward

          Re: Em Drive

          Wasn't there a suggestion that somehow the energy expended was distorting spacetime and effectively moving the centre-of-gravity (or should that be mass) of the the rig such that it appeared to generate thrust ?

          Posed as a question, not a statement because (a) I don't know, and (b) I'd like to.

  7. Stevie Silver badge

    Bah!

    So, not a tractor beam at all, but a Confinement Stream.

    When will The Register hacks get a proper grip on film metaphor jargon? It’s embarrasing.

    1. Fruit and Nutcase Silver badge
      Trollface

      Re: Bah!

      When will The Register hacks get a proper grip on film metaphor jargon? It’s embarrasing.

      I think some of us got here by being trapped by the Tractor BeamClick Bait title

  8. jmch Silver badge

    Maybe I'm misremembering, but...

    ... hasn't a tractor beam using audio waves been shown off, also here on El Reg in the last couple of years?

    1. Anonymous Coward
      Anonymous Coward

      Re: Maybe I'm misremembering, but...

      Yeah but making them work in space requires you to make the compression waves up close, not so much a tractor beam as a naval assault and my bellybutton for one, canny take it jim

    2. defiler Silver badge

      Re: Maybe I'm misremembering, but...

      Yes, but in space, no one can hear your beam.

  9. Andy The Hat Silver badge

    This isn't real.

    Unfortunately, if you read the link to the paper summary, like so many others nowadays it uses the word "simulation" all over the place.

    Just because it can be done when playing Elite doesn't mean you can do it for real ...

    (Spoiler alert for oldies: Elite wasn't based on fact)

  10. FeepingCreature

    Carbon nanotubes?

    Could you align a dozen or so of those in a circle and use them to trap and align carbon atoms to produce carbon nanotubes?

    1. bombastic bob Silver badge
      Devil

      Re: Carbon nanotubes?

      interesting idea, but would it be an economically practical/viable process?

  11. Spherical Cow Bronze badge

    A tractor beam is what is emitted by Farmer Brown's one working headlight. The beam can't pull, and neither can Farmer Brown, but his tractor certainly can.

  12. Fabrizio

    Wasn't it Gene Roddenberry in Star Trek?

    I saw Star Wars' death star being mentioned, but wasn't it Gene Roddenberry who "invented" tractor beams? (And the transporter which is being developed at the Fraunhofer institute)

    1. John Brown (no body) Silver badge

      Re: Wasn't it Gene Roddenberry in Star Trek?

      They were being used as plot devices in SF long before Star Trek, at least in print.

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Biting the hand that feeds IT © 1998–2019