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A New Spin On Physical Phenomena
f00Dave writes "Researchers have discovered "a new physical phenomenon, electrostatic rotation, that, in the absence of friction, leads to spin". I'm a bit skeptical about the implied relationship between physical "spin" (as in rotation) and quantum "spin", however. Still, this is the sort of scientific advance that renews my faith in the system. Go nerds! =]"
Hey, isn't that where they stick a piece of buttered toast to the back of a cat and let it rip?
I never could get that working. My damn cat always ate the toast.. the fat bastard.
If there can be no friction, then there can be no output. What usefulness does a spinning object with no output provide, anyway?
Life is the leading cause of death in America.
Sounds pretty cool. Does the object ever reach a maximum velocity or does it just keep on going? Where is the energy coming from?
Checking out my form of escapism.
...now my head is spinning too.
Everything in the world is controlled by a small, evil group to which, unfortunately, no one you know belongs.
science does not always have to be usefull.
I'm more excited about the "absence of friction" part...
At last my dream of building a perpetual motion machine can be realized. Take that thermodynamics!
This gives me renewed hope for my latest project, a hyperdrive engine built of old Spaghetti-Os cans and dental floss.
Roving Web-Teleoperated Robot
I don't understand this submission:
I'm a bit skeptical about the implied relationship between physical "spin" (as in rotation) and quantum "spin", however. Still, this is the sort of scientific advance that renews my faith in the system.
What system are we talking about? Why does faith need to be renewed in it? What, have you lost faith in physics because it doesn't discover new laws every day?
It sounds like they're saying the angular velocity will increase if the rotation is frictionless. Why won't this phenomenon cancel out at equilibrium amount of friction and keep the object spinning at constant angular momentum forever? I should also accelerate an object with a small amount of friction but at a slower rate than a frictionless object.
In any case, we're talking about building a perpetual motion machine here and throwing the first law of thermodymics out the window. This makes the cold fusion claims sound pretty tame. At least they said where they were getting their energy, here it seems to come from nowhere.
Jasom
ProfQuotes
Now if they want to measure political spin, we have to wait to see what research grants they apply for next...(sorry, couldn't help it.) Seriously- how do they do this without friction?
"I'd say 'Have a good time,' but arson is still illegal.
Is is just me, or does the article not really explain what it is they are talking about.
Also, a drawing of the setup would have been nice.
Third, how do they get from spinning metal thingies to quantum spin? Sounds strange...
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Lisa, you will obey the laws of thermodynamics in my house.
You read the article before commenting!
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Better yours than mine.
In this house, we obey the laws of thermodynamics!
Random is the New Order.
Maybe that's the cool thing about scientific curiosity - the things you discover don't have to have commercial value in order to be discovered.
Consider this: when it was determined that a current flowing in a wire produces a magnetic field, or when Faraday discovered that moving a magnet near a wire or coil of wire can produce a voltage, I'm sure a lot of people said, "but seriously, what would this be used for?" And they probably said the same thing about countless other things that were discovered in situations where the effect was so small that they had no apparent use.
Of course now we look back and say, "what a dumb question! How could they now know these things could be useful?" And maybe 200 years from now somebody will look at this archived announcement on Slashdot and say the same.
Then again, maybe this will turn out to be a misinterpretation of the experimental observation. Time will tell...
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It's Magic!
Oh wait, no, it's due to the Earth's rotation!
Um, no, wait, it's due to a combination of the Earth's rotation and its orbit around the Sun.
Yeah! That's it!, Yeah, I got it! Woohoo!
Actually, Stephen Hawking is expected to say "it's the spooky force at close proximity."
Honestly, between you and me, I think this will turn out to be as real as cold fusion.
Here's the journal article from Applied Physics Letters
I think they've discovered a new way to make electric motors.
1. they apply a current through a metal ball. Which induces a magnetic field.
2. They place a second metal ball near the first ball. The proximity to the first magnetic field in the second ball induces a electric potential in the second ball.
3. The third ball may be electrically connected to the suspension wires of either or both balls 1 and 2. Hence, it induces a magnetic field of it's own. The relationship between the magnetic fields in the balls, is the cause of the rotation.
Of course Murphy and I could be wrong. I've been wrong before, but Murphy never has.
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You take a 2-colored, metal-coated ping-pong ball [it can be done], and suspend it in air on a cushion of air jets. [Also can be done.]
Now stabilize it rotationally. Now stick two or three metal brushes lightly against it, and hit it with some charge. Will it spin? Will it spin continuously faster?
If so, how?
Or alternatively, we can have 3 metalized ping pong balls on three jets of air [that is, infinitely thing strings, you might say] and each brushing against three metalic brushes. Will these spin and accelerate continuously faster?
Suppose, instead of balancing them on air jets, we used strong magnetism and magneticized balls. Will it work then?
Why, or why not?
Correct Horse Battery Staple: 72 bits of entropy. Enter "Correct H" into google. When it generates the phrase, that's
There's a good reason why the quantum spin was named spin in the first place: A charged particle with spin exhibits a magnetic moment, and so does a rotating charged sphere. However, electron spin is quantized differently from rotation, so we know it's not really rotation.
Escher was the first MC and Giger invented the HR department.
So, they created an iron sphere with a magnetic field, and it started to spin, ever so slightly. Don't you think that this field could just have been moving through some other magnetic field, and this caused the spin?
Moderation: Put your hand inside the puppet head!
The article is very confusing, and makes several leaps that even the researchers don't promulgate.
Basically, what seems to be going on here is that one charges up metal spheres to see how they interact. This is a way of testing EM theory. Now, as is commonly known, charging a metal sphere will eventually have the charge distributed uniformly on the surface, and eventually static. However, it takes a non-zero amount of time to reach these static states. What these boys have done is charge 3 spheres (presumably) simultaneously, and then observe physical spin (rotation) in the spheres.
Well, inhomogenities in the surfaces can have slightly non-uniform charge currents during the charging process. All it would take is a slight asymmetry, and the charge on two spheres (let alone three) could and would provide a torque to the other(s) via the usual Coulomb interaction.
is the cry of the un-imaginative.
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The Applied Physics Letters paper is just two pages long. There is no new physics here. Here's the skinny.
Sphere A is charged up; the two others, B and C, are at different distances from A. Each sphere is polarized in a non-uniform way (because each sphere has two hemispheres, one closer to the charged sphere and the other farther... just as tides form on Earth due to the moon).
The potential at the surfaces of B and C might be uniform but the charge distributions are not: they are dipole. Due to this dipole interaction (the more negativey charge hemisphere of one sphere wants to be closer to the more positively charged surface of the other sphere), Spheres B and C then tourqe to a different angle and will either a) stay there in the presence of some friction or b) oscillate back and forth in the absence of friction. Of course, there is always some element of friction due to the air and wire, but one can compensate by also oscillating the potential of A to make positive feedback, I imagine.
The press release was, in this physics grad student's opinion, horrible. Implications that this research has some impact on our understanding of electrostatics or (gasp) quantum mechanics is irresponsible. It's a cute trick, though, and I'll bet it will find applications in mico-,nano-tech and perhaps other research areas (e.g. experiments requiring precision angular measurements ).
Nanotech basically. They have basically discovered a way to use a distribution of electric charges on a configuration of three sphere to start one of the spheres rotating. This is different from current electric motors; they use magnetic fields to start things rotating. This kind of engine would use a lot less current to generate motion than conventional electromagnetic motors. This would be good for building little machines; it's really hard to make electromagnets at the subatomic scale, but metallic spheres? Much easier. And static charge? It's hard NOT to get something with static charge on it down at that scale.
Having said that, this is purely a proof-of-concept thingy. What they did was just say, "Look, we can use this simple setup to create rotation". It's like they stuck a magnet near another magnet dangling on a string ang made it rotate. That's a long way from an electromagnetic motor, but it is a first step...
Aprocryphal story related to me by my academic advisor:
William Gladstone, the Chancellor of the Exchequer, was invited to witness a demonstration of Faraday's electrical equipment. Gladstone asked, "This is quite interesting, Faraday, but of what practical worth is it?" Faraday replied, "One day, sir, you may tax it."
.f00Dave
that this is the first time anyone has applied electricity to some metal balls. How come this hasn't been discovered until now? Is this phenomenon confined to metal balls only?
:sniff sniff::
It makes one wonder what undiscovered physical properties can be found by applying a DC current to other objects!
I smell hot dogs!
Dewey, you fool! Your decimal system has played right into my hands!
I think this is an example of an overly-zealous press release from a university employee trying to make it sound more exciting than it is. The actual article (+ errata) by the researchers can be found atp rog=normal&id=APPLAB000080000015002800000001&idtyp e=cvips&gifs=yes
http://ojps.aip.org/getabs/servlet/GetabsServlet?
Sorry, if you aren't browsing from an institution that subscribes to Applied Physics Letters, you probably won't be able to download the article for free. But I'll be happy to paraphrase what I understood from the article:
This phenomenon was purely predictable from Coulomb's law and Gauss's laws of electrostatic attraction/repulsion. Many of you should have learned about these in freshman physics. The spheres were arranged in an assymetric pattern, so rotation isn't breaking any kind of symmetry. If you arranged their spherical balls in a mirror image pattern, the rotation will reverse. The authors aren't trying to say they measured some kind of new mystical force that hasn't already been understood for 100's of years but simply that there could be an engineering application that no one had thought of before.
I'm inclined to agree with the original poster's comment that this has nothing to do with quantum mechanical spin.
Continued rotation against resistance from a static charge seems strange to me.
I wonder if they've adequately controlled against the phenomenon of "electric wind"?
They're "holding the potential constant" on the central sphere, despite any leakage from irregularities in its surface. The two uncharged spheres nearby should create a stronger field in their direction. Corona discharges toward the space between the spheres could result in a net outward motion of air there, and inward motion of air between the outer and central spheres. Friction of this air against the outer spehres would provide a rotational force, in opposite directions on the two spheres, with no net force on the central sphere.
Try again in a HARD vaccuum.
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I see hidden importance in the exact placement of the spheres, the angles and distances at which they are separated, which are not explained in the article. What I see happening is the spheres being positioned in such a way that the Coulomb forces act primarily (entirely?) in a tangential fasion on the two free-floating spheres, resulting in net rotation instead of net axial displacement. Could be merely a trigonometric stunt rather than new electrostatic observations.
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