Questions like these are always tough. QCD is notoriously hard to calculate, so maybe the effect is just some quirk in the approximations we use. So maybe it doesn't tell us "new" physics, but refines what we have. OTOH, it could be something more fundamental about the standard model, some kind of coupling or broken symmetry, and that could tell us where the standard model needs to go next.

It would be interesting if it has something to do with the fact that a muon is very nearly the mass of a pion, and maybe there's some kind of enhancement process there (though by no means am I saying this is the case, or even if it is plausible, it just strikes me as an interesting coincidence).

The 1st sentence of the 2nd paragraph states that "Scientists have been able to calculate the radius of a proton ... for some time using the charge of the proton that orbits around it...." It should be corrected to read "the charge of the electron that orbits around it"

daqman: the problem is that you can't use "the simple model" where an electron orbits classically. It's all quantum mechanics at that level. In a way, where you expect it to be most often is 'inside' the nucleus itself; though the nucleus is just such a very very small volume that such a comparison only makes sense when you compare it to all the other similarly small volumes within an atom.

But following from your idea, the muon would be even *more* likely to reside within the proton's volume because of its increased mass.

That being said, I'm sure the theorists have already accounted for that changed charge distribution when they speak of what they expect the proton's size to be. What this 'problem' is is that the proton's volume still doesn't match that expectation. (Also the EM force is way way weaker than the strong force, and so maybe it doesn't really affect the size at all)

Anyone with access to the original paper? I'm just curious to know if they tried the same measurements with an extra muon.

This comment has been removed by a moderator.

The head for the old and new experiment suspects the measurement of the Rydberg constant, thought to be one of the most precise ones, are off. [ https://www.quant...-puzzle/ ] Another suspect could be the Lamb shift calculation.

@daqman: The electron cloud orbitals (or "orbits" in your non-QM model) are decided by EM forces of the particle fields, the masses are negligible and even more mass differences.

There are other sorts of atom radius by the way, but this is the EM one.

@shavera: To nitpick, it is only the low energy S orbital where the electron (or muon) visit the nucleus much. The other orbitals are outside, not that it hinders the electron/muon field ripples (particles) being found inside at very low probability.

@TKIA: http://science.sc...6300/669 (from the Quanta article),

Over the past six years various researchers have offered theories to solve the puzzle, most of which have involved ways to preserve the Standard Model, but to date, the puzzle still remains.

Is the Standard Model worth preserving? There are increasing reasons why it needs a complete rethink.

This comment has been removed by a moderator.

There are increasing reasons why it needs a complete rethink

Standard Model is modern version of epicycles - its fitted to data with many arbitrary constants, so it's not so easily to disprove it.

No, it is very obviously not epicycles. It is self contained, houses the 5 fundamental forces (with the new Higgs boson = interaction), and has 3 generations in both charged and neutral (neutrino) leptons - the same number of neutrino generations predicted by Standard Cosmology. [Planck legacy archive.]

The Standard Model of particles has a lot of non-arbitrary constants that are fitted, and it is unknown why so far.

By the way, the old claim of "epicycles" is philosophical, and rejected by nature: nature insists in being simple. (Say, having just 18 particle fields in Core Theory. [ Low energy quantum physics version of semi-classical physics = Standard Model + graviton; http://www.prepos...-shirts/ ]

Sorry, I meant 18 quantum fields obviously, not the confusing "particle fields".

No, it is very obviously not epicycles

@torbjorn_b_g_larsson
just in case you didn't know: you're talking to zephir's latest incarnation/sock
reason, logic and evidence will not be heard, read or considered because it directly contradicts her religious belief in aether/DA etc ... she's only here to proselytize and seek converts

just sayin'

.

.

Is the Standard Model worth preserving? There are increasing reasons why it needs a complete rethink

@regMORON
1- the standard model is based upon empirical evidence and validated physics

2- your own model is based on your personal delusional belief and no evidence (you can't even post valid references or evidence to support your claims)

3- the SM may need adjustment, but all Theories in science likely will need this because we don't have all the info

if anything requires a complete rethink it is your book and pseudoscience beliefs which are proven chronic lies

This comment has been removed by a moderator.

This comment has been removed by a moderator.

Let me take a leap off the deep end and see where it winds up. One way magnetic monopoles could be hidden is if trying to isolate a monopole required more energy than creating a new monopole pair. Hmmm. The color force has three flavors, but that is just a mapping problem. Say red is North and anti-red is South, yellow, blue and their antiparticles become mixes of North and South. Think if the cube root of minus one as the mixing angle.

What do we gain from mapping quarks to magnetic monopoles? It should explain this effect. (Which becomes a test for the theory.) The quantum of magnetic charge will be large compared to the quantum of electric charge, but we already knew that the color force is stronger than the electric part of the electromagnetic force. The fine structure constant then implies a quark has a magnetic charge about 137 times the charge of an electron.

Don't quarks mass much more than this model requires? Not really. Gluons get involved.

This comment has been removed by a moderator.

Given that a proton and an electron may converge and within the nucleus charge will always comply to charge, i.e. the opposite charges will be closer than the repulsive charges; one does not need the standard model or strong and weak forces, since these will be supplied by charge. Geometry, then will define how an atom is confined. Therefore, it is rejectable that the standard model defines anything, as it is unnecessary. It may also be shown, however unnecessary, that the standard model is even sufficient. To continue as a theory is actually the mystery.

Given only two diametrical spherical fields can be shown as necessary and sufficient to define atoms and space. One should not overestimate to zero the effects of all charge within every space.

Magnetic mono-poles does not define magnetism as defined by a current loop or the time variation of the E field in 3 dimensions. Hence, a magnetic mono pole is an impossibility. This is known and empirical physics. A study of EM theory versus particle physics is the correct physics, not this.

Given that a proton and an electron may converge and within the nucleus charge will always comply to charge, i.e. the opposite charges will be closer than the repulsive charges; one does not need the standard model or strong and weak forces, since these will be supplied by charge. Geometry, then will define how an atom is confined. Therefore, it is rejectable that the standard model defines anything, as it is unnecessary. It may also be shown, however unnecessary, that the standard model is even sufficient. To continue as a theory is actually the mystery.

Given only two diametrical spherical fields can be shown as necessary and sufficient to define atoms and space. One should not overestimate to zero the effects of all charge within every space.

I meant the SM is unnecessary and not sufficient.

This comment has been removed by a moderator.

@Hyperfuzzy

A bunch of unmitigated rubbish! Scientifically inspired word salad. No basis in any form of reality.

There! I got that off my chest.