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IndisputableMonolith.Action.Noether

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This module defines the J-action functional on real-valued trajectories together with its time and space translation invariances. Researchers deriving conservation laws from Recognition Science cost functionals would cite it to connect the action principle to Noether's theorem. The module imports the Hamiltonian formulation from the J-action and the general Noether result from cost stationarity, supplying the concrete action-level objects used downstream.

claimLet $S_J[ q ] = 0$ denote the J-action on trajectories $q: I → ℝ$. Time-translation invariance of $S_J$ implies conservation of the conjugate energy $E = p^2/(2m) + V(q)$, while space-translation invariance implies conservation of momentum $p = m q̇$.

background

The module sits inside the Action domain and imports the Hamiltonian formulation obtained from the J-action via Legendre transform of the small-strain Lagrangian $L(q, q̇) = ½ m q̇² - V(q)$. It also imports the QFT Noether theorem that extracts conserved quantities directly from cost-stationarity of the underlying functional. The central object is the real-valued J-action whose translation symmetries are expressed through the sibling declarations RealAction, timeShift, isTimeTranslationInvariant, spaceShift and their associated flow maps.

proof idea

This is a definition module, no proofs. It declares the action functional, the shift operators, the invariance predicates, and the two conservation statements energy_conservation_of_J_action and space_translation_invariance_implies_momentum_conservation as direct applications of the imported Noether theorem.

why it matters in Recognition Science

The module supplies the action-level foundation required by EnergyConservationDomainCert, which certifies energy conservation along Newtonian trajectories. It completes the concrete step from the general cost-stationarity Noether theorem (QFT-006) to the specific conservation laws of the J-action, closing the link between the Hamiltonian derivation and domain-certified conservation statements.

scope and limits

used by (1)

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depends on (2)

Lean names referenced from this declaration's body.

declarations in this module (11)