High-energy theory
Most of these problems take Fermi's theory of beta decay apart. It stops working at an energy you can calculate, and that is how the W boson was anticipated decades before anyone saw one. The rest ask what a theory is allowed to contain.
The same formula, applied to a heavier leptonYour amplitude grows and it should notCounting everything that runsWhat the spectrum has to containTurning off a graviton massHow much symmetry a theory is allowed to haveHow many orders are worth computingChecking a collaborator's seriesWhere an approximation starts being goodSetting the small mass to zeroWhere a coupling stops being smallWhere a circle stops getting smaller
solve firstidea builds on ideaproblem is aboutmentioned in passingrelated, neither firstAn arrow points from the thing you need to the thing that needs it.
Not connected to anything yet (12) — these need a prerequisites or related line, a concepts line, or a [[glossary-link]] in their prose.