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Science

British Scientists Reverse Casimir Effect 347

Posted by CmdrTaco
from the where's-my-hover-car dept.
An anonymous reader writes "The Telegraph reports that Scientists at the University of St. Andrews have developed a technique to cause the Casimir effect to repel instead of attract. This discovery could lead to near frictionless machines or in theory even levitation."
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British Scientists Reverse Casimir Effect

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  • wait... (Score:4, Insightful)

    by flanker (12275) on Monday August 06, 2007 @07:34AM (#20128893)
    Isn't it "repel" rather than "repeal"?
  • Oh no! (Score:5, Funny)

    by Anonymous Coward on Monday August 06, 2007 @07:34AM (#20128895)
    Gasp, that means we will have to repel one of the laws of seance.
  • uplifting (Score:3, Funny)

    by bobby1234 (860820) on Monday August 06, 2007 @07:35AM (#20128899)
    How says science cannot be uplifting.... literally.
  • by Dystopian Rebel (714995) on Monday August 06, 2007 @07:35AM (#20128905) Journal
    This could be put to immediate use in the USA, where much bad legislation needs to be repealed and they need to attract fewer blockheads to a career in politics.
  • casmir (Score:5, Funny)

    by edittard (805475) on Monday August 06, 2007 @07:36AM (#20128915)
    I'm not a big fan of knitwear at the best of times.
  • Hmm (Score:2, Funny)

    by Anonymous Coward
    I have a feeling that this breakthrough will eventually lead to the development of giant flying mecha.
    You heard it hear first, on slashdot.
    • I have a feeling that this breakthrough will eventually lead to the development of giant flying mecha.


      Given that the Casimir effect actually produces enough force (well, pressure) at tens of nanometres distances between the two plates, that'll be some really tiny giant mecha ;)
  • Soon we can do away with stupid things like elevators..
  • repeal vs. repel (Score:4, Informative)

    by Laebshade (643478) <laebshade@gmail.com> on Monday August 06, 2007 @07:38AM (#20128925)
    It's "repel" as in "the body odor of submitter repels women worldwide", as opposed (heh) to repeal, which means, "to remove or reverse a law".
  • Or they'll vaporize the universe with this contraption. I suppose somebody's out there looking to make a weapon out of the thing.
    • Re: (Score:2, Insightful)

      Or they'll vaporize the universe with this contraption. I suppose somebody's out there looking to make a weapon out of the thing.


      Probably. Many major scientific breakthroughs have come from researchers working on weapons technology. And vice-versa -- many new weapons technologies have come from researchers working on scientific breakthroughs.

      Imagine causing all of the atoms in a tank to repel each other. Messy.
    • Or they'll vaporize the universe with this contraption. I suppose somebody's out there looking to make a weapon out of the thing. /quote>

      Step 1: Weaponize Casimir reverser
      Step 2: Figure out how much money to demand from the world governments so you don't use the weapon
      Step 3: Profit!
    • by Anonymous Coward on Monday August 06, 2007 @08:40AM (#20129355)
      I have a masters in physics, and although im not an expert in these things, i believe i have a better working knowledge than parent.

      In the quantum description of the electromagnetic field, there is no such thing as uniformly zero field - even in completely empty space, there are oscilations in the field spread over all modes (ie. wavelengths). It can be compared to an ocean or pond in stormy weather where there will allways be *some* waves.
      Now, if we have a geometry consisting of two flat opposing plates, only certain wavelengths corresponding to the distance between the plates will be allowed. Thus by increasing or decreasing the distance between the plates, we can deside which zero-point wavelengths will be allowed, and it is such that the situation where the plates are very close are energetically favorable, hence we will see the two plates attract each other and this is known as the casimir force which has been measured many times in the experiment. Its important to realize that its not charges on the plates which are doing the work - everything is kept charge neutral. Its vacuum doing work :-) .

      (by manipulating the geometry of the plates, inserting lences, etc. its then theoretically possible to make the plates repel instead, which is what the article is about)

      Anyway. My point is. This is not like nuclear chain reactions. The experimental conditions under which you see these effects are extreme (as in: the truck on the street or the cellphone in the assistants pocket will ruin it). Its a neat discovery, but the doom and gloom is completely uncalled for.
  • when they can figure out how to build those artificial gravity doohickeys used on the USS Enterprise and other spaceships.
  • by therufus (677843) on Monday August 06, 2007 @07:45AM (#20128979)

    Micro or nano machines could run smoother and with less or no friction at all if one can manipulate the force.
    Obi-Wan was right after all! I can become a Jedi!

    So was it only me that heard Sir Alec Guinness read that line out?
  • by Mathinker (909784) on Monday August 06, 2007 @07:46AM (#20128981) Journal
    The discovery is not to be belittled, but both the article and the poster somehow forget to mention that the "levitation" which is talked about is on the order of nanometers (check the Wikipedia article on the Casimir effect). Far from the kinds of stuff you see stage magicians do.
  • by Mike1024 (184871) on Monday August 06, 2007 @07:48AM (#20128997)
    Wikipedia [wikipedia.org]:

    In physics, the Casimir effect or Casimir-Polder force is a physical force exerted between separate objects, which is due to neither charge, gravity, nor the exchange of particles, but instead is due to resonance of all-pervasive energy fields in the intervening space between the objects. [...] Since the strength of the force falls off rapidly with distance it is only measurable when the distance between the objects is extremely small. On a submicron scale, this force becomes so strong that it becomes the dominant force between uncharged conductors. Indeed at separations of 10 nm -- about a hundred times the typical size of an atom -- the Casimir effect produces the equivalent of 1 atmosphere of pressure (101.3 kPa).
  • by PIPBoy3000 (619296) on Monday August 06, 2007 @07:49AM (#20129007)
    From this article [zpenergy.com]:

    Now, Leonhardt and Philbin have calculated that the Casimir force between two conducting plates can turn from being attractive to repulsive if a "perfect" lens is sandwiched between them. A perfect lens can focus an image with a resolution that is not restricted by the wavelength of light. Such a lens could be made from a metamaterial made of artificial structures that are engineered to have negative index of refraction -- which means that the metamaterial bends light in the opposite direction to an ordinary material.

    According to the researchers, the negative-index metamaterial is able to modify the zero-point oscillations in the gap between the surfaces, reversing the direction of the Casimir force. Indeed, the researchers believe that this repulsive force is strong enough to levitate an aluminium mirror that is 500nm thick, causing it to hover above a perfect lens placed over a conducting plate. Since the Casimir force acts on the length scale of nanomachines, manipulating it could be important for future applications of nanotechnology.
    To summarize, nothing has been built yet. It's possible that it could be built, though you'd have to make a "perfect" lens in the tiny space between the two plates. Unfortunately, every "perfect" lens I've heard of tends to be wavelength-specific and relatively large (compared to the gap the Casimir effect requires). It may be that these are just engineering hurdles, but it may also be physically impossible to pull off.
    • Re: (Score:3, Funny)

      Oh, well, then I guess we're not going to leave it up the guys who made the original lenses on the Hubble, now are we?
    • And dont forget negative refractive index materials for the lens. Is it real or imaginary. From what little I remember, refractive index is the ratio of the speed of light in a medium and the speed in vacuum. Negative index means, negative speed of light? Speed is not a vector. How does one get negative speed?

      Reminds me of the brilliant proof for the existence of perpetual motion machines, that assumes a magnetic monopole.

      • Well, since we know from Einstein that as soon as the speed of light is involved, it all depends on the position of the observer, i.e. where you are in the system, and when I stand in the traffic jam on a Monday, subjectively I can sense what negative speed is. You should try it.
      • How does one get negative speed
        IANAP, but I would wager a guess that negative (directionless) speed would involve some kind of phase shift by 180deg which would 'negate' the orginal wave. That would be EXACTLY the kind of senseless convention that scientists use ;) .

        Just in case... you saw it here first :)

        Cheers!
      • Sorry, refractive indexes actually have very little to do with the speed of light in the various mediums. (At least, not directly.) Instead, they have to do with the materials permeability and permittivity to electromagnetic fields. (That is: How fast it magnatizes, and how fast it polarises.)

        Negative refractive index materials have already been demonstrated, for specfic wavelengths. Haven't managed on visual wavelengths yet, as far as I can remember.
      • by Doc Ruby (173196) on Monday August 06, 2007 @10:10AM (#20130283) Homepage Journal
        Negative refractive index materials, called "lefthanded metamaterials [wikipedia.org]" are already in use.
  • huh? (Score:5, Funny)

    by apodyopsis (1048476) on Monday August 06, 2007 @07:50AM (#20129019)
    What is this? a spelling contest or a discussion about a new scientific discovery?

    Sheesh. Anybody would think /. is populated purely by obsessive pedants with nothing better to do.

    oh..
  • by objekt (232270) on Monday August 06, 2007 @07:55AM (#20129045) Homepage
    "dry glue" effect that enables a gecko to walk across a ceiling.

    "Spider-pig, Spider-pig,
    Does whatever a Spider-pig does."

  • *applause* (Score:2, Interesting)

    Nicola Tesla would be proud. This sounds like all the electrical field tuning he did back in the 1800's only on a smaller scale and for different purposes.

    Modulating fields like this seems to me to be some sort of thrusting action although they don't come out and say it.
  • by tenco (773732) on Monday August 06, 2007 @08:03AM (#20129105)
    http://www.iop.org/EJ/journal/-page=forthart/1367- 2630#Papers [iop.org]

    Quantum levitation by left-handed metamaterials
    Ulf Leonhardt and Thomas Philbin
    Provisionally scheduled for August 2007

  • Woohoo (Score:2, Funny)

    by zonestalker (883074)
    now where is my hover skateboard?
  • by Doc Ruby (173196) on Monday August 06, 2007 @08:05AM (#20129131) Homepage Journal
    A humorous page about these British scientists' work by St Andrews physics Professor Leonhardt explains their work on Casimir "levitation" [st-andrews.ac.uk].
  • Being British... (Score:4, Insightful)

    by clickclickdrone (964164) on Monday August 06, 2007 @08:07AM (#20129139)
    1. Invent/discover something cool
    2. Tell everyone about it
    3. ???? 4. NO Profit

    It's sad to say that here in the UK we never learn and have a long and distinguished history of brilliant research followed by total fumbling of the ball and making no money out of the discoveries whatsoever.
    • by Pecisk (688001) on Monday August 06, 2007 @08:53AM (#20129459)
      And this is bad because...?

      Woah, you want to tell me that there are scientists who actually do science for...err...sake of science, not money? What a surprise!

      Without irony, I personally don't believe in profiting from BIG discoveries. If you get some applications going from that discovery, then it is understandable that you can and you will profit from them, but not from discovery itself.
    • by Chief Camel Breeder (1015017) on Monday August 06, 2007 @09:18AM (#20129645)

      From the researcher's point of view:

      1. Discover something cool.
      2. Publish results in peer-reviewed journal and get famous.
      3. Get better research job (or more money, security in current one).
      4. Profit!

      Step 3 doesn't have to involve selling technology.

    • Re: (Score:3, Funny)

      by ichigo 2.0 (900288)
      Contrary to popular belief, the world does in fact not revolve around money.

      That is all.
  • by petes_PoV (912422) on Monday August 06, 2007 @08:10AM (#20129165)
    Apart from saying it uses a "special lens" there's no information about how the team managed to reverse this effect. In fact there's more space given to the hocus-pocus aspects (that every straight thinking /.'er dismissed in an instant) than of any actual science.

    The thelegraph is supposed to be one of the more serious british dailies. So heaven help us all if this is what they pass off as a science story.

  • Casimir... (Score:3, Funny)

    by Rhaban (987410) on Monday August 06, 2007 @08:14AM (#20129187)
    I did not know this guy => http://en.wikipedia.org/wiki/Casimir_(dinosaur) [wikipedia.org] had a physics degree.
  • by TychoCelchuuu (835690) on Monday August 06, 2007 @08:23AM (#20129233) Journal
    You can tell the journalistic standards at the Telegraph are through the roof. From the article:

    The force is due to neither electrical charge or gravity, for example, but the fluctuations in all-pervasive energy fields in the intervening empty space between the objects and is one reason atoms stick together, also explaining a dry glue effect that enables a gecko to walk across a ceiling.

    This wasn't enough for me, so I wandered over to Wikipedia:

    In physics, the Casimir effect or Casimir-Polder force is a physical force exerted between separate objects, which is due to neither charge, gravity, nor the exchange of particles, but instead is due to resonance of all-pervasive energy fields in the intervening space between the objects.

    The only changes to the Wikipedia article lately have been a link to this article, which is sort of meta. Wikipedia linking to an article plagiarizing from, of all places, Wikipedia. Cute, but also a little sad.
  • by Remus Shepherd (32833) <remus@panix.com> on Monday August 06, 2007 @08:26AM (#20129245) Homepage
    I am a physicist, but these subjects are often beyond me. Still, let me try a short explanation. This seems, to me, rather an important discovery.

    The Casimir effect happens when you get two surfaces very nearly touching. Virtual particles emerge on the other side of the surfaces and force them together. Virtual particles being, well, virtual -- very short-lived and low-energy -- this effect only occurs when the surfaces are very, very close to one another.

    What's intriguing about the Casimir effect is that it is extracting work from the zero point energy of the universe, the base energy field of empty space. (Yes, even a total vacuum contains virtual particles, and thus some energy.) It is not immediately obvious how to make this useful, however, if the only way to tap into the zero point energy is to destructively sandwich two expensive materials together.

    Reversing the Casimir effect is brilliant. By placing a perfect lens between the two materials, the virtual particles create a repulsive force. This could, as stated, create a levitation effect by preventing the surfaces from ever touching. 'Levitation' is a strong word, though. It'll 'levitate' a nanometer or so above the other surface, which is only good for reducing the friction between them to zero. So 'frictionless surfaces' is probably the keyword we should be using here.

    I'm intrigued because it would seem to be easier to generate power from the zero point energy with a repulsive effect than an attractive one. So this could also be the first step toward a zero point energy generator -- free energy. What will they think of next...
    • Re: (Score:3, Interesting)

      by 4D6963 (933028)

      I'm intrigued because it would seem to be easier to generate power from the zero point energy with a repulsive effect than an attractive one. So this could also be the first step toward a zero point energy generator -- free energy. What will they think of next...

      My thoughts exactly, although I found myself unable to word them thusly, which brings us to this inevitable question : Wouldn't it violate the second law of thermodynamics?

      • Re: (Score:3, Interesting)

        by vigmeister (1112659)

        Wouldn't it violate the second law of thermodynamics?
        I'd assume there's no violation unless the surfaces move closer to each other as a result of the force since no work gets done. But the validity of that statement lies with my rephrased question: "Does any potential energy get 'created' in the process of increased attraction?"

        Cheers!
        --
        Vig

        • The energy isn't created really, is kept from moving into the area between the plates.

          Let me explain further:

          Heisenberg's uncertainty principle says you can't know where a particle is, or it's momentum, at the same time. That applies to space too. For any point in space, you can't know if there's a particle there or not.

          Therefore, the reality is that the vacuum is boiling all the time with particles popping into and out of existence all the time. Particle soup. For another interesting effect of this, check out Hawking radiation.

          Anyway, if the plates are close enough together, no particles can be popping into existence in that space, because it's too small. It's literally small enough that if there were a particle there, you'd know it's position and momentum, and that is NOT allowed.

          So, the situation you've set up is that you have two plates very close together, with particles appearing and disappearing on one side of the plates (the outside surfaces) but not on the inside surfaces. That means that there's a pressure created which forces the plates together.

          No energy is created because what you're doing is preventing particles (energy) from appearing inside the plates. The energy of a vacuum is not zero because of those particles. The energy inside the plates is zero (zero point energy).

          The problem is that once the plates have moved together which is work, you don't get any more work out of the system unless you move the plates back apart.
    • I am a physicist, but these subjects are often beyond me. Still, let me try a short explanation.

      That's fine. The non-physicists here will gleefully take up the slack.

  • by VitrosChemistryAnaly (616952) on Monday August 06, 2007 @08:34AM (#20129301) Journal

    Their discovery could ultimately lead to frictionless micro-machines with moving parts that levitate.
    Finally that fast talking dude will have a job again!
  • In Theory (Score:5, Funny)

    by j00r0m4nc3r (959816) on Monday August 06, 2007 @09:00AM (#20129517)
    I hereby theorize that cramming peanuts into your arsehole will cause levitation.

    There, now that I've officially theorized this, I can say, "In theory, cramming peanuts into your arsehole will cause levitation." and it's perfectly true.
    • Re: (Score:3, Funny)

      by mcrbids (148650)
      I hereby theorize that cramming peanuts into your arsehole will cause levitation.

      Well, I tested your theory, three times.

      And I've documented the effects, three times.

      I got the same results every time.

      No levitation, but I won't be able to sit down for a week.
  • by mrjb (547783) on Monday August 06, 2007 @09:12AM (#20129605)
    FTA: "The force is due to neither electrical charge or gravity, for example, but the fluctuations in all-pervasive energy fields in the intervening empty space between the objects and is one reason atoms stick together, also explaining a "dry glue" effect that enables a gecko to walk across a ceiling." ... and now that scientists have figured out how to reverse the Casimir effect, this will soon enable geckos to walk on the floor.
  • by Kazymyr (190114) on Monday August 06, 2007 @06:34PM (#20136265) Journal
    Hallelujah. My username is finally getting the credit it deserves.

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