#A.19:5.2.1.3 Product – Combination CS₁ ⊗ CS₂ = CS⊗.

Preface node heading:a-19-5-2-1-3-product-combination-cs-cs-cs:29970

#What this page is

This is generated FPF reference text from the specification preface or supporting sections. It helps interpret FPF; it is not FPF Reference product documentation.

#Methodology

Use it to understand how the specification wants to be read, then return to a route, pattern, or work packet for active work. Cite generated IDs only when the wording changes the task decision.

#Content

The product of two spaces CS₁ and CS₂ is a new space CS⊗ whose basis is the disjoint union of both bases, so even same-named slots retain their source identity. Its state is a pair (x₁, x₂). For example, a product can combine internal capability Coordinates with external-condition Coordinates for a readiness use. The product does not aggregate them: any cross-slot aggregation uses a declared B.1 Gamma fold and any needed A.19.UNM normalization.

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Last Updated: 2026-09-03 — upstream FPF commit b999972c (github.com/ailev/FPF)