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Measurement Shows the Electron's Stubborn Roundness (scientificamerican.com)
OneHundredAndTen writes: A new article in Nature reports of a new, extremely precise measurement of the electric dipole moment of the electron. The conclusion is that, within the margin of error of the measurement, the electron remains a perfect sphere. This implies that supersymmetric theories keep running out of corners to hide, that another nail is driven into their coffin, and that string theory looks less and less compelling. By lighting up the molecules with lasers, "the scientists were able to interpret how other subatomic particles alter the distribution of an electron's charge," reports Scientific American. "The symmetrical roundness of the electrons suggested that unseen particles aren't big enough to skew electrons into squashed oblong shapes, or ovals. These findings once again confirm a long-standing physics theory, known as the Standard Model, which describes how particles and forces in the universe behave."
I do not think they are claiming anything of the sort. They are saying that, as alternative theories become less likely, there is more reason to believe the Standard Model could be correct.
Yes.
Bingo. You answered the apparent contradiction yourself.
Electrons are point-like particles -- meaning they're so small as to not have a well defined size if any. You describe the electron density for the orbitals of electrons -- which can be many shapes. That's more about the probability of where to find an electron in relation to the type of atom or the molecular bond between atoms.
This article is about the magnetic moment of the electron. So, if an electron were in a known position, this experiment shows that it doesn't matter from what direction in 3-D space another particle approaches this hypothetical electron, it will still get the exact same response. So, the field force-lines around the electron are perfectly spherical in strength.
This was important because electrons have a magnetic moment (like a bar magnet) that we call spin -- either spin up or spin down... which you're likely familiar with in chemistry as the rule that 2 electrons can share the same orbital as long as they are opposite spins. Some alternate theories propose that this means some parts of the electron are more charged than others or that the shape was more like a spinning charged ring instead of a sphere.
We've long known that nothing is actually spinning to create "spin." It's just a label for a quantum property that was somewhat useful as an analogy long ago. Yet, there remains this strange source of angular momentum. This experiment just confirmed that even though there is a magnetic dipole moment, that property doesn't mean the particle itself is distorted in order to express the property.
What's even weirder is that "spin" being a quantum property, is in a strange superposition state until measured and the spin axis can change depending upon the experiment.... with no intermediary direction for the spin. It's a binary choice -- spin up or spin down for any axis tested.... and seemingly random.
TL,DR -- this test just showed that the particle we call an electron is the same when approached from all angles - same charge, same interaction. So, it's "spherical" even though it's point-like. The probability distribution of an electron's location in atomic orbitals or molecular bonds is a different subject.
It does mention the word "sphere" 13 times though. The words "Cube" or "Pyramid" are not present either.
Now if only the Standard Model were an actual theory, instead of a list of empirical observations.
In many scenarios electrons are not well-described by point particles. Their de Broglie wavelength is in the order of one Angstrom, depending on how fast they move. That means you have to take their wave nature into account and the only reasonable description is via the Schroedinger equation (for non-relativistic velocities), or the Dirac equation (for relativistic velocities).
Every end has half a stick.
Everyone always wants to talk about the little tennis balls, but no one ever talks about the tiny little golden retrievers chasing them around.
Now if only the Standard Model were an actual theory, instead of a list of empirical observations.
It is a theory that made testable predictions (like the Higgs boson) that were later proven to be correct via experiment. If that's not a theory then nothing is.