Talk:Free neutron decay

Neutron lifetimes vary by 8-9 seconds depending on what method you use to measure them.

https://d2r55xnwy6nx47.cloudfront.net/uploads/2018/02/Neutron_Lifetime_560.jpg

Afaik, the difference remains unexplained. Keith David Smeltz (talk) 14:09, 6 June 2018 (UTC)

I learned about this problem after recently reading [1] This appears to be something that should get added to List_of_unsolved_problems_in_physics#Nuclear_physics I've found some good refs: 2009 [2], 2014 [3], 2016 [4], 2018 [5] [6] -- Limulus (talk) 05:01, 30 July 2018 (UTC)

I agree this should be on the unsolved problems in physics list. Are there any other decay modes for free neutron decay? The Quanta article discusses the weakness of the test if there is a decay mode that does not produce a proton.J Mark Morris (talk) 07:21, 18 February 2019 (UTC)

Transitions

"The beta decay of the neutron described in this article can be notated at four slightly different levels of detail, as shown in four layers of Feynman diagrams in a section below.

A schematic of the nucleus of an atom indicating  β−  radiation, the emission of a fast electron from the nucleus (the accompanying antineutrino is omitted). In the Rutherford model for the nucleus, red spheres were protons with positive charge and blue spheres were protons tightly bound to an electron with no net charge. : The inset shows beta decay of a free neutron as it is understood today; an electron and antineutrino are created in this process.

n0  →  p+  +  e−  +  ν e

The hard-to-observe  W−  quickly decays into an electron and its matching antineutrino."

This article begins by showing one decay diagram but then immediately switches to talking about a decay path that actually occurs but which isn't shown in that decay diagram. Diagrams are supposed to illustrate something that is being taught to the reader. They lose their value when they are used to illustrate something that the reader is apparently supposed to forget because you change the subject as soon as the reader looks at the diagram. Please consider the complexity of the pattern of transitions that is used in the article. Promiscuously jumping around from one subject to another is not helpful.

When you encounter these promiscuous transitions the probability is high that there is a better way. For example, you could say something like "When the first tests/experiments were being conducted in/around <date>, what was measured/discovered was the decay pattern shown in the following diagram

<diagram>

The decay pattern shown, in which a neutron decays into a proton, an electron and an electron antineutrino, is still a useful approximation today. (But there are more precise ways of looking at it and blah, blah, blah) <diagram(s)> (yada yada yada)..."

Just moving from <diagram with no W-> to (actually there's a W- particle in there) will lead to readers rightly questioning why you presented the diagram in the first place. Please read the important article "The Magical Number 7 Plus or minus 2". You give a diagram with 4 elements. Then you introduce a fifth element which may or may not negate the need to remember the diagram with 4 elements. You're already confusing the crap out of the reader because the reader doesn't know what they need to remember or what they need to forget. Your reader is not necessarily a nuclear physicist. You can't just correct the problem later in the article because you've already confused the reader and the reader was quite likely only looking for that first diagram but you've given the reader a cue that that first diagram might not be important because it has no W- particles. Remember, YOUR READER IS NOT NECESSARILY A NUCLEAR PHYSICIST. Your reader wants an article that conforms to the limitations in normal human brains which tend not to have perfect memories and which always work within the constraints of "7 Plus or Minus Two", if you keep telling your reader "Ok, here's this <load 5>, but no actually toss that 5, we're doing this now, go ahead and <load 9> and yada yada yada", your reader is going to get very confused, very quickly. Please master those transition patterns and keep things as simple and possible. Please read "The Magical Number 7 Plus or Minus 2" just for a start and try to develop some intuitions about pedagogy. Pedagogy is a very difficult subject but unfortunately creating useful encyclopedias requires some understanding of it. So please read "The Magical Number 7 Plus or Minus Two" just for a start. Comiscuous (talk) 06:49, 10 October 2021 (UTC)