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10-Year Study Reveals Electron Shape

samzenpus posted more than 3 years ago | from the round-and-round dept.

Science 370

lee1 writes "In a 10 year long experiment, scientists at Imperial College have made the most precise measurement so far of the shape of the electron. It's round. So round, in fact, that if the electron were enlarged to the size of the solar system, its shape would diverge from a perfect sphere less than the width of a human hair. The experiment continues in the search for even greater precision. There are implications for understanding processes in the early universe, namely the mysterious fate of the antimatter."

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So its like a dick then? (-1)

Anonymous Coward | more than 3 years ago | (#36245558)

Or not?

Re:So its like a dick then? (-1)

Anonymous Coward | more than 3 years ago | (#36245616)

In size or shape?

Re:So its like a dick then? (2)

scififan (2199644) | more than 3 years ago | (#36245894)

Thats depends on a dick. If its yours, that sure its about same size

Units (2)

Nemyst (1383049) | more than 3 years ago | (#36245588)

I know the site is probably trying to be approachable, but what's wrong with saying 1e-29 m instead of this absurd measurement of 0.000000000000000000000000001 cm? This is getting close to the Planck length; no matter what you compare it to, it won't be a length you can intuitively grasp.

Re:Units (4, Insightful)

Twinbee (767046) | more than 3 years ago | (#36245620)

The 0.000...001 version maybe visually represents the amount better.

Re:Units (1)

Anonymous Coward | more than 3 years ago | (#36245684)

From the reference article :
We obtain de = (2.4±5.7stat±1.5syst)×1028ecm, where e is the charge on the electron, which sets a new upper limit of |de|10.5×1028ecm with 90 per cent confidence.

Re:Units (0)

Larryish (1215510) | more than 3 years ago | (#36245748)

... the mysterious fate of the antimatter.

Mysterious?

Really?

Who lets this crap through?

Is this some sort of cheesy hipster reality show?

What has Slashdot become?

Bueller? Bueller? Bueller?

Re:Units (4, Insightful)

mattack2 (1165421) | more than 3 years ago | (#36245798)

What's wrong with calling it mysterious? The theories say there should be equal parts matter & antimatter.. There doesn't seem to be.. So it's a mystery.. Thus, as an adjective, it is mysterious.

Re:Units (0)

Anonymous Coward | more than 3 years ago | (#36245984)

Is this some sort of cheesy hipster reality show?

Ooooooo! Thanks! And work Snookie and The Situation into it - great idea! It'll be a new science reality show!

SNOOKIE: So, like, um, these electrons go spinning and they're like, really round *hehehehehe* and, um, the help with my suntan!

SITUATION: Yeah. What a Situtation. *Flexes with shirt off.*

SNOOKIE: Let's party!

SITUATION: *Flexes*.

Awesome! We'll post updates here on Slashdot!

I'll think 'll suggest that Snookie be the next interview for Slashdot to Taco!

Re:Units (-1, Redundant)

dziban303 (540095) | more than 3 years ago | (#36246278)

What has Slashdot become?

Nice 6 digit uid there, kid.

Re:Units (0)

Anonymous Coward | more than 3 years ago | (#36245772)

OK. It's 1.98838782e-30 rods.

Re:Units (1)

M0j0_j0j0 (1250800) | more than 3 years ago | (#36246042)

Or 6.21371192 × 10-33 miles , remember this is an international board ....

Electrons out of shape (1)

FishTankX (1539069) | more than 3 years ago | (#36245590)

I could just see it now.

The crystal latice questions the electron about it's excercise.

Electron: I'm in shape, round is a shape.

why am I not surprised ? (-1)

Anonymous Coward | more than 3 years ago | (#36245594)

why am I not surprised ?

round? (0)

Anonymous Coward | more than 3 years ago | (#36245598)

Is it round or spherical?

Under what conditions? (3, Interesting)

blair1q (305137) | more than 3 years ago | (#36245608)

Is it always round, even when it's tunnelling through a potential wall?

And I assume that by "round" they mean that every level curve of the probability amplitude has constant radius.

And, uh, what did they do about that Heisenberg thing? If you can't tell where the electron is relative to your frame of reference, how is the electron supposed to tell where a certain constant on its level curve is relative to its own frame of reference?

Re:Under what conditions? (2, Informative)

Anonymous Coward | more than 3 years ago | (#36245784)

And, uh, what did they do about that Heisenberg thing? If you can't tell where the electron is relative to your frame of reference, how is the electron supposed to tell where a certain constant on its level curve is relative to its own frame of reference?

The measurement was indirect --- they didn't observe the electron but instead observed the lack of any distortion in the shape of the molecule. I guess this observation does not require them to pin point the position of the electron.

Re:Under what conditions? (1)

cheeks5965 (1682996) | more than 3 years ago | (#36245918)

how is the electron supposed to tell where a certain constant on its level curve is relative to its own frame of reference?

Oooh electron, you got burrrned!

Re:Under what conditions? (5, Informative)

SETIGuy (33768) | more than 3 years ago | (#36246314)

Is it always round, even when it's tunnelling through a potential wall?

I think that the way they are translating the physics into English is awful. I'm not sure I fully understand their method, but I'll try to restate. What they actually found was that they electric dipole moment of the electron was very small. It it were not that small, they would have seen changes in the wave function. From there they go to stating that if the electron can be modelled as a charge distribution or a charged object, that object would be spherically symmetric with dipolar radial deviations of less than that very small number. But more precisely, the wave function of an electron behaves as if it represents a particle that has a electric dipole moment less than 1.05E-27 ecm.

If course you couldn't actually make measurements to determine whether that dipole moment is a property of a physical shape of the electron or is an intrinsic property. Nothing we have can probe those size scales, and if you could you'd have particle antiparticle pairs popping up everywhere from the energy of the collisions. You might even create a new universe at those energies. Everything we've done so far suggests that the electron has no structure, but that's on much larger scales/lower energies.

Curious question (4, Interesting)

gcnaddict (841664) | more than 3 years ago | (#36245618)

What other possible shapes were theorized for an electron? What are these theories based on? What difference would an egg-shaped electron make in the grand scheme of things?

I know why we should care, but I wouldn't mind knowing what theories exist to justify different shapes.

Re:Curious question (1)

Anonymous Coward | more than 3 years ago | (#36245770)

Egg shaped one throws away everything we know about quantum physics, in short. As solution to Schroedinger equation is spherical (in the lowest energy state),

Re:Curious question (3, Interesting)

blair1q (305137) | more than 3 years ago | (#36245840)

Well, having now read TFA (i do that when i'm bored and the topic is ultra-geeky like electron shape must be), it seems all they could have been measuring here is the shape of the electrical and quantum fields around the electrons in not just an atom but a molecule (of the sexily named ytterbium fluoride).

So what they've done is proved solenoidality of both; i.e., that they obey the inverse-square law to an anal-retentive degree; i.e. that force = A*1/r^(2+x) where |x| 1e-29. We only know gravity's solenoidal to about 8 significant figures, for comparison.

Interestingly, the shape of the fields around the nuclei of the atoms in the molecule ought to have played some part. I wonder if they haven't accidentally also proved that nuclei are round to a similar degree.

Re:Curious question (1, Flamebait)

Relic of the Future (118669) | more than 3 years ago | (#36245796)

There don't need to be any competing theories: we have *a* theory and it says "round". Technical capabilities improved so we can test that theory to higher precision. So we tested it. The theory still stands. But the absence of a competing model has ZERO to do with whether or not we should test the current theory.

If you want exactly two sides to every argument, go into political journalism.

If the test had come back negative, THAT would be interesting, and I assure you there would soon be plenty of theories (and then lots of tests!)

Remember, the most interesting phrase in science isn't "Eureka!", it's "Well that wasn't what I expected..."

Re:Curious question (4, Insightful)

gcnaddict (841664) | more than 3 years ago | (#36245830)

My good sir, I merely asked a few questions. I made no statement indicating an expectation of multiple theories, merely a query for any in the event that any happened to exist.

As an aside, it would do you wonders to investigate new methodologies of conveying written information. Your response, most notably the capitalization, the usage of asterisks for emphasis, and the snide remark about political journalism, appeared to have a not-terribly-subtle hint of condescension. As someone who wants to learn more, this is something I most certainly do not deserve after asking a benign question.

Re:Curious question (0)

Anonymous Coward | more than 3 years ago | (#36246040)

Well, the article does say that the electron was found to be *surprisingly* spherical. That would suggest a different shape was expected?

Re:Curious question (2)

lee1 (219161) | more than 3 years ago | (#36246130)

That seems to be just stupid headline writing. Nowhere in the body of the article do we encounter a scientist expressing surprise at the result.

Re:Curious question (1)

Lord Kano (13027) | more than 3 years ago | (#36246116)

But the absence of a competing model has ZERO to do with whether or not we should test the current theory.

The absence of a competing model increases the importance of testing the current theory.

LK

Re:Curious question (4, Informative)

blank axolotl (917736) | more than 3 years ago | (#36246236)

Actually, according to the paper the electron is aspheric in many theories, including the standard model (the best theory we have). From the article abstract:

The electron is predicted to be slightly aspheric, with a distortion characterized by the electric dipole moment (EDM), de. No experiment has ever detected this deviation. The standard model of particle physics predicts that de is far too small to detect, being some eleven orders of magnitude smaller than the current experimental sensitivity. However, many extensions to the standard model naturally predict much larger values of de that should be detectable. This makes the search for the electron EDM a powerful way to search for new physics and constrain the possible extensions.

Re:Curious question (0)

Anonymous Coward | more than 3 years ago | (#36245892)

What other possible shapes were theorized for an electron?

It's so fundamental that it suppose to be shaped like a brick.

Re:Curious question (1)

Anonymous Coward | more than 3 years ago | (#36245936)

A much better article, with predicted numbers for how spererical the electron should be according to different theories:

http://www.newscientist.com/article/mg21028145.100-ultracold-measurements-reveal-shape-of-the-electron.html

Re:Curious question (1)

Anne_Nonymous (313852) | more than 3 years ago | (#36245972)

>> What other possible shapes were theorized for an electron?

I was hoping they would be dollar sign shaped, so I could tell my father, "Well, as it turns out, you *are* made of money.".

Re:Curious question (1)

elashish14 (1302231) | more than 3 years ago | (#36245982)

[talking out of my ass here, IANA physicist]

You'd expect an atom to be mostly spherical right? Well if you measure the radius of an atom, you'll find that it can fluctuate. Knowing by how much the radius of an atom fluctuates might, for example, give you an idea of the angular momentum or kinetic energy of its constituent particles. I presume that the size and shape of the electron could fluctuate in similar ways and might give an indication of what physics governs its mechanical properties.

What I'm getting at is that maybe the actual measurement of the electron's radius isn't what's so important; rather it's knowing the deviation in these measurements that might yield some interesting scientific value. Keep in mind that 1e-29m is still over 5 orders of magnitude larger than the Planck length [wikipedia.org] so maybe if we make a little more progress, we'll start seeing some really interesting physics.

Re:Curious question (1)

Attila the Bun (952109) | more than 3 years ago | (#36246094)

What they mean is that they have tested the symmetry of the electron and found it to be equivalent in all directions, like a sphere. The hair's-width thing is just an analogy to describe the degree to which that symmetry has been tested; the electron does not have an intrinsic size or shape. If there were any detectable asymmetry, that would imply that the electron and positron are not perfect opposites, and may explain why there is so little antimatter in the universe.

Re:Curious question (1)

bigsexyjoe (581721) | more than 3 years ago | (#36246148)

Well they tested it's "shape" by seeing electrons have any wobble. They apparently found no wobble. Meaning that they are either little spheres, or IMHO more likely they have no wobble because they have no size. There are good reasons to think they fundamental indivisible particles already; because of the uncertainty principle the constituents of such a small particle would have to have a lot momentum.

Re:Curious question (5, Informative)

fermion (181285) | more than 3 years ago | (#36246164)

From what I can tell ia this has to do with Standard Model which predicts equal quantity of matter and anti-matter in the universe. As far as can be determined, there is an asymmetry that is hard to explain. One way to explain this asymmetry in the quantity of matter is if there was a physical asymmetry between the electron and positron. The asymmetry would not exist in the particles themselve, but in the virtual particles surrounding them.

These virtual particles are tiny compared to atomic matter and exist for short amount of time, such a short amount of time thier very existence is below the uncertainty thresholds. They are a consequence of the fundamental uncertainty in position and momentum. They are created out of the vacuum.

So the question the experiment attempts to answer is does the electron behave like an object that reacts symmetrically in all dimensions, or is there so aberration, that is, is it not a perfect sphere. To a very high accuracy the paper claims that it is a sphere.

However that is not the full story. The paper is based on the idea that the aspherical shape would be larger than the standard model predicts. Adjusted models predicts a larger aspherical aberration. Since this experiment did not detect large aberrations, these other models, extensions of the Standard Model seem to be less than accurate. Form what I read, the standard model predictions are orders of magnitude lower than current sensitivity [nature.com] so it remains unclear if the electron acts like a sphere or something that is almost like a sphere.

What this experiment does is provide a novel and fascinating method to probe subatomic particles, as well as establish an upper limit on how big the abberation could be. Good science.

Re:Curious question (2)

JonyEpsilon (662675) | more than 3 years ago | (#36246168)

Good questions! This is actually one of the central motivations for measuring this is. The standard model of particle physics predicts that the electron will be round. But most physicists think that the standard model isn't the full story. The interesting thing is most of the proposed extensions/replacements to the standard model predict that the electron will be somewhat distorted. To give a concrete example, supersymmetric theories, which are viewed by many as the most promising avenue for extending our theories of physics, usually predict a distorted electron.

Amazing! (1)

Vasheron (1750022) | more than 3 years ago | (#36245624)

It's incredible that the shape of one of the most fundamental particles in the Universe has one of the simplest mathematical descriptions! Is it a coincidence or is there some deeper meaning to this fact?

Re:Amazing! (0)

Anonymous Coward | more than 3 years ago | (#36245820)

arguably a sphere is one of the most complex mathematical descriptions you could use to describe something.

Re:Amazing! (0)

Anonymous Coward | more than 3 years ago | (#36246128)

The surface of a sphere is all points that are exactly R distance from location O. Now you describe a cube.

Re:Amazing! (1)

doshell (757915) | more than 3 years ago | (#36246208)

You can use the exact same definition, except that the distance is defined according to the L-infinity [wikipedia.org] norm instead of the Euclidean one!

Re:Amazing! (1)

blair1q (305137) | more than 3 years ago | (#36245844)

They didn't measure the particle, they measured the forces between particles.

Intelligent Design with Balls! (1)

mevets (322601) | more than 3 years ago | (#36246136)

The deeper meaning is that the FSMs meaty balls must also be as round and consistent as these electrons. It is a fulfillment of the recipe.

Re:Intelligent Design with Balls! (0)

Anonymous Coward | more than 3 years ago | (#36246180)

It also means his balls aren't hairy, unless they're significantly larger than our solar system.

flaw? (0)

vonkohorn (688787) | more than 3 years ago | (#36245634)

The shape of an electron is a sphere over 10 years? That's like saying the shape of the ocean is smooth as glass averaged over 10 years. Sure it's true, but it's misleading.

Re:flaw? (0)

Anonymous Coward | more than 3 years ago | (#36245672)

Using a very precise laser, they made careful measurements of the motion of these electrons. If the electrons were not perfectly round then, like an unbalanced spinning-top, their motion would exhibit a distinctive wobble, distorting the overall shape of the molecule. The researchers saw no sign of such a wobble.

If people have a question, why don't they check if the article has it first before asking?

I feel irritated when someone is sitting at a computer and asks me questions about simple things. HEY. YOU'RE AT A COMPUTER. GOOGLE IT.

Re:flaw? (1)

Anonymous Coward | more than 3 years ago | (#36245870)

why? what did google say?

Re:flaw? (1)

kvvbassboy (2010962) | more than 3 years ago | (#36245696)

I didn't read the TFA, but that clears my confusion. I thought that they discovered that electrons were "deterministically" spherical.

Re:flaw? (1)

kvvbassboy (2010962) | more than 3 years ago | (#36245766)

Also:

That's like saying the shape of the ocean is smooth as glass averaged over 10 years. Sure it's true

Citations needed.

Think about it. Taking a huge number of readings over 10 years and averaging them, could give any irregular polyhedron, but it turns out to be an elegant shape.

Re:flaw? (2)

JonyEpsilon (662675) | more than 3 years ago | (#36246188)

It took us ten years to build the experiment. We didn't average for ten years!

I called it! (0)

Anonymous Coward | more than 3 years ago | (#36245636)

I called it!

Shape? (1)

Anonymous Coward | more than 3 years ago | (#36245640)

Uh, call me naive but I thought that electrons were point-particles and had no shape (being single-dimensional).

--AC

Re:Shape? (5, Funny)

Warlord88 (1065794) | more than 3 years ago | (#36245726)

First I studied they were particles, then I studied they are actually mixture of waves and particles. Then I studied you cannot actually pinpoint it at all, and all you can know is probability density of its existence in space. Now, I read that they are extremely round.
My mind is full of fuck.

Re:Shape? (5, Interesting)

doublebackslash (702979) | more than 3 years ago | (#36246170)

This is simplified, don't take this completely literally, but get this first. I'll use a car analogy.

You and several other clowns are in a clown and some of them are juggling. You are driving so you can't look at them. You can't look because you are doing a precision maneuver with several other clown cars. As part of the act they are also exchanging juggling objects with other cars. Even though you can't look at the jugglers you can sense what they are doing due to the fact that their motions and transfer of momentum are throwing you off course. It is important that you stay on course to make the jump. God help you if you hit the ramp like like the last guy did, but the kids like to see this act up close.

If the jugglers are throwing around tennis balls your course will be effected differently than if they were throwing juggling pins.

Now, back in the world of the article you've got the same thing. Atoms with electrons flying around and shared by chemical bonds. The shape of the electrons effects the shape of the molecule. More specifically the shape of the charge around the electron effects the shape.

Don't try to watch the objects being juggled, watch the clown cars try to stay in formation on their way to the jump over lion pen.

It took a long time because the measurements are so delicately precise and spurious data had to be discounted and filtered from the signal. The measurements weren't averaged but they were mercilessly filtered and subjected to analysis to take the "noise floor" down this low.

I am not a physicist. Someone correct me or clarify if I was dead wrong. Thanks!

Re:Shape? (0)

lyml (1200795) | more than 3 years ago | (#36245742)

You're not naive, you're wrong.

Re:Shape? (1)

ChrisMP1 (1130781) | more than 3 years ago | (#36246026)

Sir, I know you're trying to be polite, but you shouldn't hold back so. It is imperative that we right the incorrect whenever we see them on the Internet, or else the Internet might be (gasp!) wrong! Ugh... the very thought makes me shudder.

Re:Shape? (2)

bigsexyjoe (581721) | more than 3 years ago | (#36246160)

This experiment shows they have no wobble. I think that's pretty consistent with them being point particles, don't you?

Round?! (-1)

Anonymous Coward | more than 3 years ago | (#36245644)

Is it round, or spherical?

all that wave particle jazz (3, Interesting)

Sebastopol (189276) | more than 3 years ago | (#36245680)

So.... it's a sphere when it is a particle?

For years, I've been trying to un-brainwash myself out of the early models of the electron as a little ball whirring around a nucleus, and convert to the probabilistic electron cloud model, as well as the wave/particle hybrid nature.

My head is about to explode. Can someone who is a physicist please chime in?

Re:all that wave particle jazz (5, Insightful)

Daniel_Staal (609844) | more than 3 years ago | (#36245716)

Your head exploding is a perfectly normal reaction to trying to comprehend modern physics. Carry on.

Re:all that wave particle jazz (0)

Anonymous Coward | more than 3 years ago | (#36246124)

Must make for some interesting freshman lectures.

The cloud model is inaccurate (0)

Anonymous Coward | more than 3 years ago | (#36245904)

Our instrumentation at those levels is too "slow" and imprecise to "see" things clearly. Don't get too wrapped up in probability shields and the electron cloud model. It's going to be disproven and this will lead up to it, mark my words/call it a "prophecy" of sorts. It's said God's universe is without end, and Einstein said it was all relativistic. Our solar system's just an atom, and constellations are molecular constructs to a larger perspective and the reverse holds true infinitum on levels relativisitically lower than ours, and higher/larger than ours as well.

Re:all that wave particle jazz (1)

CrimsonS (1108367) | more than 3 years ago | (#36246006)

I'm no physicist but isn't the probabilistic model related to the position of electrons around the nucleus of an atom. It has nothing to do with the form of an electron.

Re:all that wave particle jazz (4, Interesting)

NoSig (1919688) | more than 3 years ago | (#36246088)

It is neither a particle nor a wave, so there is no "when it is a particle/when it is a wave". Instead, it is something whose behavior is like that of a particle in some ways and like that of a wave in other ways, but it is never actually a wave or a particle. It is its own thing - the analogies to waves and particles are just there to aid understanding, they are not accurate descriptions. I imagine that what is meant is that the density of the probability field (or whatever the correct term is) decreases uniformly in all directions with distance - no direction is favored over another.

puuurfect (5, Insightful)

fragfoo (2018548) | more than 3 years ago | (#36245708)

Maybe its shape is indeed a perfect sphere and the "width of a human hair" is just a measurement error. How more precise they want to get, until its shape diverges a human hair from a perfect sphere when enlarged to the size of the galaxy? Is there an end to measurement errors? Am i making any sense? I think not, its late at night :x

Re:puuurfect (2)

blair1q (305137) | more than 3 years ago | (#36245874)

It will no longer be possible to measure the error, when you are bald.

Point particles (1)

barlevg (2111272) | more than 3 years ago | (#36245712)

Aren't electrons point particles? How can something be spherical if it has no radius?

Re:Point particles (1)

mfnickster (182520) | more than 3 years ago | (#36245852)

"It's like Sputnik - spherical, but quite pointy in parts."

Re:Point particles (0)

Anonymous Coward | more than 3 years ago | (#36245860)

Heisenberg's uncertainty principle [wikipedia.org] will give any point-like particle a natural size based on its mass (and momentum).

Re:Point particles (1)

Smigh (1634175) | more than 3 years ago | (#36245890)

Exactly my thought when reading the headline. What sense does it make to talk about the shape of a point?

Re:Point particles (0)

Anonymous Coward | more than 3 years ago | (#36246126)

Maybe they mean the classical equivalent radius, which is something like 1e-15m ... That would give an error of 1 part in 1e14. I think that's about the number of hairs in the solar system...

Size of the solar system? (2)

Zandamesh (1689334) | more than 3 years ago | (#36245736)

What is the radius of the solar system anyway? Furthest planet (40 AU)? Furthest comet orbit (50000 AU)?

But more importantly, how much digits of pi would you need to describe this sphere accurately?

Re:Size of the solar system? (1)

wrathpwn (1995376) | more than 3 years ago | (#36246078)

Just off the top of my head, I'd say 32 digits of pi, but I'm probably wrong.

Re:Size of the solar system? (0)

Anonymous Coward | more than 3 years ago | (#36246302)

What's up with you and your measure unit's? Why measuring in Australia's when we can use Russia's?

Human hair? (1)

hkz (1266066) | more than 3 years ago | (#36245764)

10^-27cm (the spherical error in the article) is 10^-29m. The upper bound on the electron's radius is 10^-22m (Wikipedia). The solar system is roughly 1.5*10^13m in radius (Wolfram Alpha), so 3*10^13m in diameter. If you'd inflate the electron to the size of the solar system, scaling by 3*10^35, the spherical error would be 3*10^6m, which is more than twice the diameter of Earth, according to my calculations.

Re:Human hair? (0)

Anonymous Coward | more than 3 years ago | (#36245838)

That must mean electrons make a pretty awful hack when gouging up hairballs!

Re:Human hair? (1)

blair1q (305137) | more than 3 years ago | (#36245886)

Inhuman handwaving.

Universal Unit Of Measure? (0)

Anonymous Coward | more than 3 years ago | (#36245808)

Could these finding be used as a Universal standard for measure? who the heck cares about what an A.U. is if you live outside the solar system?

What about texture? (3, Funny)

i ate my neighbour (1756816) | more than 3 years ago | (#36245814)

Is there a tiny ( - )sign on its surface?

Re:What about texture? (0)

Anonymous Coward | more than 3 years ago | (#36245994)

I guess in the middle of everyone trying to be insightful about this article, they've missed the awesome joke you just made :P

Relative comparison *wildly* off AFAICT (1)

Omega Hacker (6676) | more than 3 years ago | (#36245832)

The numbers in the article don't work for me.....

Electron radius (wikipedia): 10^-22 meters
Article's claim of error-from-round: 10^-29 meters
Relative error: 10^7, or 0.1 parts per million

"Radius of solar system" randomly chosen as Eris's avg orbit fo 68AU (wikipedia): 1.017 * 10^13 meters
Relative error scaled to size of solar system: ~1.017 * 10^6 meters, or ~1017km

Now I don't know about you, but my hair isn't exactly 1000km thick, eh?

Avg thickness of human hair (answers.com): 0.1mm, or 10^-4 meters
Ratio by which Science Daily apparently cannot count: 10^10

Re:Relative comparison *wildly* off AFAICT (1)

JonyEpsilon (662675) | more than 3 years ago | (#36246292)

We used the compton wavelength of the electron as the size scale for this analogy. You could argue that the 1/e radius of the electron/positron virtual particle cloud would be a better measure, and this is closer to the classical radius (off the top of my head, it's late here), which would give an accuracy measured in mm rather than microns. The 10^-22 number comes from interpreting ion trap measurements of the electron's g-factor, comparing them to QED theory. To some extent, the question of the electron's size depends on what you mean by size and how you might choose to measure it. Jony

Well, it must follow then.. (1)

multipartmixed (163409) | more than 3 years ago | (#36245836)

..that sub-electronic particles either do no exist, or they have no* mass. Otherwise the electronic equator would be at least a teensy* bit fatter, due to its spin.

*no and teensy are both about one over infinity. Plus or minus a tad.

Re:Well, it must follow then.. (1)

shutdown -p now (807394) | more than 3 years ago | (#36245908)

In the current model, electron has no deeper structure - it's truly fundamental, alongside photon, quarks etc.

George Michael (0)

Anonymous Coward | more than 3 years ago | (#36245876)

Is it as round as George Michael's butt?

At last! (1)

roesti (531884) | more than 3 years ago | (#36245882)

At last, the flat-electron rabble can finally give it a rest.

If an electron were enlarged that much... (0)

Anonymous Coward | more than 3 years ago | (#36245910)

It would /be/ the size of the solar system!

What the hell use? (0)

Anonymous Coward | more than 3 years ago | (#36245914)

What the hell use is an analogy that uses the size of the solar system? No reasonable person can visualize that any more than they can visualize the size of an electron.

An analogy has to be human scale.

Whoop (0)

Anonymous Coward | more than 3 years ago | (#36245916)

Don't hate modern theories or science. Hate popular press coverage of it. I know I do.

Obligatory (1)

creat3d (1489345) | more than 3 years ago | (#36245948)

Scaled to the size of the Library of Congress, its shape would diverge from that of a perfect sphere by less than 0.00049 dead interns in the closet. Or 0.0033 homosexual affairs with assistants, for the Republicans...

What they really measured (0)

Anonymous Coward | more than 3 years ago | (#36245950)

The experiment really measured the electric dipole moment, which was found to be order of magnitude 10^-28 De, with an error bar of the same size, meaning that its equal to zero within experimental error.

The electric dipole moment gives the one-dimensional deviation of the electric field of the electron from radial symmetry; if its not zero, the electric field of the particle would be egg-shaped. So, the measurement isn't really of the shape of the particle itself, but of its interaction with other charged particles.

Define "shape" (1)

shutdown -p now (807394) | more than 3 years ago | (#36245954)

How, exactly, do you define the concept of "shape" for something like an electron?

I mean, for a macroscopic object, our "common sense" definition of shape is the boundary at which an outside interaction would feel resistance - if you poke it, that's where you feel the counterforce (weak as it may be). This is actually caused by molecules interacting between each other, but at that point already the concept of "poking" something is kinda hazy, since you already get all that quantum mumbo jumbo strong enough to be prominent. By the time you go down to electron, the common sense approach would break apart entirely; so what is the definition, then?

Re:Define "shape" (1)

creat3d (1489345) | more than 3 years ago | (#36245980)

Scale down your imaginary poking finger and the notion of shape will remain the same. Worked for me!

quadropole moment (0)

Anonymous Coward | more than 3 years ago | (#36246036)

I was a particle physicist in a previous life. I think, put simply, what is being referred to is attempting to measure higher moments of the electric field of the electron, ie dipole, quadropole, and higher moments. Basically what they are saying is that they measured the higher moments to be zero with a much smaller error bar than previously measured.

What's even crazier (4, Funny)

straponego (521991) | more than 3 years ago | (#36246156)

...is that God did that freehand.

All the anti-matter is... (2)

RL78 (1968236) | more than 3 years ago | (#36246158)

"Imperial's Centre for Cold Matter aims to explain this lack of antimatter by searching for tiny differences between the behaviour of matter and antimatter that no-one has yet observed. Had the researchers found that electrons are not round it would have provided proof that the behaviour of antimatter and matter differ more than physicists previously thought. This, they say, could explain how all the antimatter disappeared from the universe, leaving only ordinary matter. Professor Edward Hinds, research co-author and head of the Centre for Cold Matter at Imperial College London, said: "The whole world is made almost entirely of normal matter, with only tiny traces of antimatter. Astronomers have looked right to the edge of the visible universe and even then they see just matter, no great stashes of antimatter. Physicists just do not know what happened to all the antimatter, but this research can help us to confirm or rule out some of the possible explanations."


Is it possible that we can't find anti-matter because it's all in one place?

So an electron is not a sphere! (1)

bigsexyjoe (581721) | more than 3 years ago | (#36246202)

This is incredible! Sure they might be almost spherical, but the shape is slightly off! This small difference could have profound theoretical implications. First it means that an electron has volume, second it means they might have an inner structure to create that shape. Very interesting indeed. Might lead to new physics.

Re:So an electron is not a sphere! (0)

Anonymous Coward | more than 3 years ago | (#36246296)

I think you may be misinterpreting the summary. The precision of their measurements put an upper bound on deviations from perfectly sphericity. The electron can be no more than "the width of a human hair in the solar system" off from being a perfect sphere, or they would have measured it.

What about the p, d and f orbitals? (0)

Anonymous Coward | more than 3 years ago | (#36246204)

They must not be talking about the p, d and f orbitals:

http://4.bp.blogspot.com/-fjQAZidF9Kc/Tb9KIl_jaOI/AAAAAAAAADs/-jdC7QhF7QM/s1600/ch9orbitals1.jpg

Round. (1)

Roachie (2180772) | more than 3 years ago | (#36246234)

Yea... its round. Thanks for the grant.
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