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Water Flows Uphill

Posted by michael on from the now-you-see-it dept.

An anonymous reader writes "The BBC are reporting James Dyson's new garden feature, a waterfall with water flowing uphill. Apparently, he wanted to recreate an Escher drawing."

16 of 365 comments (clear)

  1. Simple... it's antiwater by Anonymous Coward · · Score: 5, Funny

    Antiwater (two part antihydrogen and one part antioxygen) is repelled by the force of gravity.

    1. Re:Simple... it's antiwater by Anonymous Coward · · Score: 5, Informative

      If only antimatter was repelled by gravity. Antimatter is just normal matter with reverse charge and spin, so it obeys all normal physical laws. So-called "negative matter" would be repelled by gravity, but we don't know if it even exists or can be made.

    2. Re:Simple... it's antiwater by nomadic · · Score: 5, Funny

      If you drink anti-water, do you become thirsty?

    3. Re:Simple... it's antiwater by SEE · · Score: 5, Informative

      The troubles here are two:

      1) We have no experimental evidence as to how antimatter reacts to gravity (beond a couple of small ones where the externally-caused experimental error bars render the results statistically meaningless)

      2) We don't know how gravity works. In GR, yes, antimatter has normal mass and reacts normally to gravity. But GR is not the last and final word on how gravity works, and several models otherwise fully consistent with known experimental data allow for anitmatter to be affected to a greater or lesser extent than normal matter by gravity, even to the point of sign reversal.

      Since we have no experimental evidence and several potentially correct theories that give different answers, the only conclusion is that we don't know. The general opinion is that animatter is affected by gravity as normal matter, but we don't know that it is.

    4. Re:Simple... it's antiwater by thoughtstream · · Score: 5, Funny
      Close, but no cigar. The clue is in the article, where it's explained that a "thin later of water" is used.

      In other words, he's using anti-time! By covering the ramps with a thin coating of later (rather than the usual layers of earlier that surround most objects) the water actually flows backwards in time. This, of course, causes its normal downhill motion under gravity to occur retrotemporally, giving the fluid the appearance of syntemporal uphill motion.

      Contratemporal epitaxy, eh? I tell you, that Dyson's a genius!

    5. Re:Simple... it's antiwater by Alsee · · Score: 5, Informative

      We don't have experimental proof yet, but we have overwhelming reason to believe antimatter fall down just like matter. You can work it out based on hysical constants and conservation of energy in a matter/antimatter annihilation. It is explained in this physics FAQ.

      If antimatter is repelled by gravity then you either have a violation of conservation of energy, or physics constants are not constant.

      -

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      - - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
    6. Re:Simple... it's antiwater by misterpies · · Score: 5, Informative

      There can be no doubt, for solid physical reasons, that antiparticles behave identically to regular particles when it comes to gravity.

      First of all, the only relevant physical quantity to determine how something is affected by gravity is its mass (and equivalently, in relativity, energy). That's practically the definition of gravity -- the force one body exerts on another by virtue of its mass. In physicist speak, the gravitational field "couples" to mass/energy. Any force having an origin in some other physical quantity is by definition not gravity.

      Now we have plenty of experimental evidence -- eg from particle accelerators that antimatter has positive mass, just like regular matter. Indeed, antiparticles have IDENTICAL masses to their corresponding real particles. Therefore they must be affected in the same way as regular matter by gravity.

      Secondly, in both relativistic and quantum frameworks, gravity can only be understood if it is always attractive. In other words, mass can only be positive. In quantum terms, this comes out of the fact that gravity must be "spin 2" field. (There's a nice book by Feynman on his attempts to come up with a quantum theory of gravity that explains why it has to be spin 2).

      Thirdly, according to quantum field theory the vacuum is filled with "virtual" particles and antiparticles -- that's the zero-point energy of the vacuum. Now the whole point about the vacuum is that it's the lowest possible energy state. If anti particles had negative mass-energy, they'd be in a lower energy state than the vacuum, which means that they'd be stable compared to the vacuum and would not decay back into the vacuum.
      If that were true, the universe would long ago have filled up with antiparticles...

      --
      The author of this post asserts his moral rights.
  2. Interesting... by Stephonovich · · Score: 5, Informative
    Quite an elaborate optical illusion. The original drawing is also worth looking at.

    (-:Stephonovich:-)

    --
    "Who needs reincarnation when we've got parallel universes?" -Me
    1. Re:Interesting... by Amiga+Trombone · · Score: 5, Funny

      Escher makes my brain hurt. It's so obvious something is wrong, but it's impossible to focus on it. Argh, this makes me want to gouge out my eyes.

      Indeed. It reminds me of a few companies I've worked for.

    2. Re:Interesting... by Afrosheen · · Score: 5, Funny

      Dude, you just helped me coin a new term:

      Escher-esque Management.

      Let's push it onto a few blogs and see if it doesn't end up in Wired next month.

  3. Uphill water flow at Disneyworld since 1971.. by droopus · · Score: 5, Informative

    Since the 70's, there has been a cave on Tom Sawyer Island in Disneyworld in which water appears to flow uphill.

    The Imagineers did it cleverly with a slanted room and no point of reference. Not as geeky, but a really cool effect nonetheless which amazed me back in the day.

    --
    "The pie shall be cut in half and each man shall receive.....death. I'll eat the pie."
    1. Re:Uphill water flow at Disneyworld since 1971.. by anethema · · Score: 5, Interesting

      I always thought the most famous of these things was at the bay of Fundy. The level of the tide rises higher than the river level and causes REAL uphill rapids, and a semi illusionary uphill waterfall.

      I havent seen it myself, but I understand its quite a mind bender to see.

      There is also an optical illusion near there in..Moncton i think? You go to the base of the hill, put your car in neutral, and your car will roll up the hill. Its an optical illusion, you are actually rolling downhill, but you look and it looks uphill, no amount of thinking its downhill dispells that.

      Some very neet stuff, and example of an Eschery world in real life.

      --


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  4. More MC Escher drawing by Michael's+a+Jerk! · · Score: 5, Informative

    are at the World of Escher. The man was a genius.

    --

    I'm not Seth.

  5. i have previously achieved this same illusion by Miguel+de+Icaza · · Score: 5, Interesting

    but using a different technique. I used a strobe on a small waterfall in a dark room- this works in the same way you can sometimes see car wheels spinning in the wrong dirrection.

    When i saw dysons outdoor version while touring the flower show I hoped he had somehow used lasers to implement the strobe technique outdoors in full daylight - that would be cool. But no he is just using pumped air - no surprise really considering hes a vacuum genius :^)

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  6. Sigh... by lingqi · · Score: 5, Insightful
    Before someone tries to market their own uphill water feature, they had better be warned. James Dyson - no stranger to court battles over patents - has presumably taken care of the necessary legal business.

    Now, why would he do that? I know it might be a rhetorical question, but honestly though - all he would do, I presume, is to limit this neat but useless (admit it - this is as useless as your lava-lamp and plasma-ball (no seminal jokes please)) thing out of mainstream for a long time - instead of giving him eternal fame, etc.

    Now - an interesting question to think about is what part of our pattern-recognizing brain is responsible for *falling* for such a visual illusion? Research like this can shed light on the workings of the mind, I think.

    --

    My life in the land of the rising sun.

  7. urinals by scubacuda · · Score: 5, Funny
    Maybe he could make a urinal that does that.

    Perhaps some sort of spinoff of Marcel Duchamp's 1917 work of "art".

    Those crazy dadaists!