How statement and proof provenance work
The first chip identifies the source of the statement or construction; the second identifies the source of its local proof or verification.
- Literature-sourced: the exact statement appears in a cited source; only wording and notation differ.
- AI-adapted: a semantically identical restatement of literature-sourced material, modulo indexing, notation, and boundary cases adopted by the library.
- AI-generated: a genuinely novel statement formulated by AI, with no source for the claim itself.
These labels describe origin, not correctness: citations and verification chips remain separate evidence.
Hamiltonian recurrence under the exact finite-measure hypothesis
Statement
Let be a Hamiltonian phase datum, let be a complete invariant Borel domain, and fix . Put . Let be any finite Borel measure on invariant under . Then for every Borel , -almost every satisfies for infinitely many integers . The result is almost-everywhere recurrence for this fixed sampled map; it is not a pointwise statement about every initial state. The hypothesis also allows finite invariant measures singular with respect to ambient Liouville volume.
Facts & Assumptions
Given: A complete invariant Borel domain , a time step , and a finite Borel measure on invariant under .
Hamiltonian phase, complete-domain flow and reference measure: is the actual local Hamiltonian flow, and completeness and invariance on mean it is defined there for all real and maps onto itself.
Measure-preserving transformations and systems: invariance is for every Borel .
Poincare recurrence for finite measure-preserving systems: for a measure-preserving self-map of a finite measure space, almost every point of each measurable set returns to it infinitely many positive iterates.
Proof
Given: The phase datum, , , and [F1]–[F3].
By [F1], the flow is defined on every point of at time and maps onto itself, so is a measurable self-map. By [F2] and the hypothesis, preserves the finite measure .
Apply [F3] to and the arbitrary Borel set . Its conclusion is exactly that -almost every point of returns to infinitely many positive integer iterates.
Remarks
The theorem does not assume or prove finite total Liouville volume for . An infinite-volume phase space can still have a finite invariant probability or a finite invariant restriction, but that is a separate hypothesis.