Principles Fixing the Standard Model’s Particle Content and Gauge Groups

Determine the fundamental principle(s) or mechanism(s) that establish the selection of the Standard Model’s particle content (quarks and leptons across three families, possibly including right‑handed neutrinos) and its gauge group SU(3)c × SU(2)L × U(1)Y, or ascertain that no unique selection principle exists.

Background

After outlining guiding principles and working hypotheses for particle physics, the paper emphasizes that, despite the empirical success of the Standard Model, there is no established rationale for why Nature chose its specific set of fields and gauge symmetries. This gap persists even as effective field theories and unification ideas provide partial structure.

Resolving this would illuminate whether deeper symmetries, anomaly constraints, unification, or other mechanisms dictate the observed matter content and gauge structure, or whether environmental/anthropic selection in a broader landscape is at play.