CencovPetz.CencovFinite #
The finite/discrete Čencov (Chentsov) uniqueness theorem under continuity hypotheses.
In the purely algebraic part of the argument, one proves the scalar-multiple identity on:
- the uniform point;
- all common-denominator (“rational”) points via splitting.
This file provides the final topological step: since rational points are dense and Fisher is continuous, any continuous monotone metric family coincides everywhere with a fixed scalar multiple of Fisher.
Main result #
theorem
LeanPool.CencovPetz.MonotoneMetricFamily.eq_smul_fisher_of_continuous
(G : MonotoneMetricFamily)
{α : Type}
[Fintype α]
[Nonempty α]
{a0 a1 : α}
(ha01 : a0 ≠ a1)
(hG : ∀ (u v : ↥(tangentSpace α)), Continuous fun (p : Simplex α) => ((G.g p) u) v)
(p : Simplex α)
(u v : ↥(tangentSpace α))
: