10-Year Study Reveals Electron Shape

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."

Under what conditions?

[blair1q]

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?

Curious question

[gcnaddict]

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.

all that wave particle jazz

[Sebastopol]

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:Curious question

[blair1q]

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:all that wave particle jazz

[NoSig]

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.

Re:Shape?

[doublebackslash]

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!