Explanation of Jlog_zero in IndisputableMonolith.Cost.Jlog
(1) Plain English
The declaration Jlog_zero states that the function Jlog evaluates to exactly zero when its input is zero.
(2) Why It Matters in Recognition Science
Jlog encodes the recognition cost in additive log coordinates (equivalent to cosh t - 1). The zero value at the origin establishes the minimum cost point, supporting the non-negative cost structure used in RS cost uniqueness and ledger accounting.
(3) How to Read the Formal Statement
The Lean statement is:
@[simp] lemma Jlog_zero : Jlog 0 = 0 := by
simp [Jlog]
@[simp] marks it for automatic simplification. The proof unfolds the definition of Jlog and reduces the expression (exp 0 + exp 0)/2 - 1 to 0.
(4) Visible Dependencies or Certificates
The lemma lives in module IndisputableMonolith.Cost.Jlog and depends only on the local definition of Jlog plus Mathlib real-number tactics. It is immediately adjacent to Jlog_as_exp, Jlog_eq_cosh_sub_one, Jlog_nonneg, Jlog_pos_iff, Jlog_eq_zero_iff, and Jlog_strictMonoOn_Ici0 in the same file. No external axioms or certificates appear in the source for this declaration.
(5) What This Declaration Does Not Prove
It proves only the specific evaluation at zero. It does not establish the biconditional Jlog t = 0 ↔ t = 0, non-negativity for all inputs, strict monotonicity on the positive reals, or any link to physical constants, forcing chains, or empirical predictions.