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.
Finite Gibbs response of an observable is times its covariance with the field-coupled observable
Statement
Let be a finite nonempty set, let , fix , and for define , , and . For functions , define . Then is differentiable on and
Statement references
Facts & Assumptions
Given: A finite nonempty set , real-valued functions , and .
For every finite nonempty state set and finite real energy, the Gibbs partition sum is finite and strictly positive, and its normalized weights form a probability vector (Finite Gibbs relative entropy and free-energy minimum).
The real exponential is differentiable with derivative (The exponential function is smooth and ).
Finite sums, products, and quotients with nonzero denominator obey the ordinary derivative rules (Sums, scalar multiples, products and quotients: , , , and when ).
A differentiable real function composed with a differentiable real function obeys the chain rule (The chain rule, in one line from Carathéodory: if is differentiable at and is differentiable at , then is differentiable at with ).
Proof
For every , each is positive and finite, and is finite nonempty, so by [F1]. Thus is a probability vector, and both and are finite sums with nonzero denominator .
Since , [F2] and [F4] give . Differentiating the finite sums term by term with [F3] therefore gives and .
The denominator is nonzero by step 1.1. The quotient rule [F3] applied to yields after dividing numerator and denominator by ; by the definition of covariance in the Statement this is .