back to article Boffins brew 'Stop Light' that turns photons in fibre into memory

Sorry sci-fi fans, we're still not travelling even as far as Alpha Centauri. Rather, scientists at the Kastler Brossel Laboratory in Paris have pushed fibre-optic technology along by storing and re-emitting photons in a purely optical system. In other words, the mechanism the boffins have demonstrated constitutes an all-fibre …

  1. A Non e-mouse Silver badge

    Faster than light travel

    Faster-than-light is easy if you slow the photons down.

    The cosmological speed limit is the speed of light in a vacuum. Light traveling through different mediums can be slower. Going faster than that lower speed is entirely possible. The blue glow (called Cherenkov radiation) when radioactive material is underwater is the equivalent of a sonic boom when particles are traveling faster than light.

    1. Little Mouse

      Re: Faster than light travel

      As I understand things, faster-than-light IS easy* - it's just accelerating up to and beyond the light speed barrier that's the bitch. If you're already past it though, then it's plain sailing all the way.

      (*based on the maths involved. In practice I imagine the result would be a tad messy)

      1. Michael Wojcik Silver badge

        Re: Faster than light travel

        As I understand things, faster-than-light IS easy* - it's just accelerating up to and beyond the light speed barrier that's the bitch

        Infinite relativistic mass at C is only one of the problems posed by FTL travel. Past C, you'd apparently have imaginary relativistic mass, which could do ... odd ... things to your mechanical dynamics, for example. And there are little issues like what sort of process would let you maintain that speed outside your static reference frame (are you chucking superluminal propellant out the back?), and how you're going to deal with encountering photons that have been Doppler-shifted up to obscene energy levels.

        But the real problem is that now you've broken causality. That's arguably worse than wasting an infinite amount of energy to get to that point.

  2. Destroy All Monsters Silver badge
    Pint

    So an optical mercury delay line?

    Your physics says you don't

    And old Einstein says you won't

    And I'm boilin' up inside

    Ain't no way I'm gonna be slow this time

    Tie your Lightspeed down

    Tie your Lightspeed down

    Lock your photons out of doors

    I don't need them whizzing 'round

    Tie your Lightspeed down

    Tie your Lightspeed down

    We gonna be FTL tonight

    1. Crisp

      Re: So an optical mercury delay line?

      I was thinking RADAR too when I was reading the article :)

  3. ilmari

    So this more convenient form of optical memory than bouncing a laser beam via the reflectors left on the moon by apollo. That, btw, has been used as datastorage before.

  4. Cliff

    Oh wow that's cool

    Or at least it certainly sounds like it's cool to the layman that I am.

    1. Gordo Rex

      Re: Oh wow that's cool

      the photon captured by the cesium cloud can then be released on demand.

      How many would I need to make a photon torpedo?

      1. channel extended

        Re: Oh wow that's cool

        One. Although the more photon's you have the move destructive it will be.

  5. Old Handle

    Delay Line Memory

    Now there's a blast from the past.

    1. Michael Wojcik Silver badge

      Re: Delay Line Memory

      Wave as it goes by!

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