Leptons and interactions | Webel IT Australia

The 1st snippet does not tell use anything new, however a stereotype keyword «electric» has been introduced and applied to the ValueType Charge and the value property charge:Charge for clarification. (We could have also renamed Charge to be ElectricCharge, but applying «electric» makes this a bit clearer for now, even if one would have to re-apply it whenever the property is redefined.)

If you have been following the trail from the very beginning you might recall that the abstract block Interaction was marked as «pa:implied»; this can now be removed as the 2nd snippet confirms the concept.

The concepts 'subject to' and 'not subject to' have been represented using the existing keywords «undergoes» and «not undergoes». And sufficient to record the information (but not yet the maths) a stereotype keyword «proportional to» is introduced for Electromagnetism.

The full text from which these smaller snippets were extracted is a little clumsy:

Wikipedia: 'electromagnetism ... is proportional to charge, and is thus zero for the electrically neutral neutrinos.'

Does it make sense to say that Lepton «undergoes» Electromagnetism (a literal interpretation of the 1st snippet) when clearly NeutralLepton (a.k.a. neutrino) does not really? Note also this clarifying snippet from a separate Wikipedia page:

Wikipedia: 'A neutrino (denoted by the Greek letter ν) is a fermion (an elementary particle with spin of 1/2) that interacts only via the weak subatomic force and gravity.'

The corresponding stereotyped «undergoes» Dependency should perhaps be bumped down to ChargedLepton, with a separate «not undergoes» Dependency from NeutralLepton (and this is in fact done much later in the tutorial trail).

Don't worry too much if you hit inconsistencies like this. If you work through high quality domain source documents things typically eventually get cleaned up as a natural part of the snippet-driven Parsing Analysis process. You can use editorial devices like applying a custom «?» keyword as shown to mark such concerns until they are resolved.

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Modelling antiparticles, antileptons, and antimatter

Notes

[POLICY, STYLE]{STRICT} Webel Parsing Analysis «pa» diagrams are NOT intended as final presentation diagrams! They serve merely to traceably elicit model elements, which may then be shown in other (typically much tidier) presentation diagrams elsewhere.

[DISPLAY, STYLE, TIP]{SUGGESTED} Webel Parsing Analysis: If the dashed-line "anchors" from your «snippet» ElementGroup symbols to elicited elements make a «pa» Parsing Analysis Diagram (PAD) too hard to read, try making them light grey using symbol properties.

Snippets (quotes/extracts)

Leptons have various intrinsic properties, including electric charge, spin, and mass.

Unlike quarks, however, leptons are not subject to the strong interaction, but they are subject to the other three fundamental interactions: gravitation, the weak interaction, and to electromagnetism ...

electromagnetism ... is proportional to charge, and is thus zero for the electrically neutral neutrinos.

A neutrino (denoted by the Greek letter ν) is a fermion (an elementary particle with spin of 1/2) that interacts only via the weak subatomic force and gravity.