Four-orbit product decomposition of the exact CW profile
Provedmme_CW_2376_profile_product_splitcommutative-monoidcoppersmith-winogradexact-profilefinite-product
Let be elements of any commutative monoid, indexed by the possible five-grade triples. Weight each element by the exact CW profile multiplicity. Then the full product splits into the four supported cyclic-orbit groups:
Unsupported types have multiplicity zero and disappear. This algebraic identity is independent of tensor semantics and can be reused to reduce the 125-type product to the fifteen supported constituents.
Preamble
import Definitions.Def_mme_CW_2376_address_block open MME BigOperators
Formal statement
theorem mme_CW_2376_profile_product_split
{M : Type} [CommMonoid M]
(Q : (Fin 3 → Fin 5) → M) (m : ℕ) :
(∏ σ, Q σ ^ cw2376ProfileMultiplicity m σ) =
(∏ σ ∈ cw2376ScalarTypes, Q σ) ^ (699 * m) *
(∏ σ ∈ cw2376RectTypes, Q σ) ^ (37518 * m) *
(∏ σ ∈ cw2376CentralTypes, Q σ) ^ (307638 * m) *
(∏ σ ∈ cw2376CoupledTypes, Q σ) ^ (616627 * m) := by
sorrySource
D. Coppersmith and S. Winograd, Matrix Multiplication via Arithmetic Progressions, Journal of Symbolic Computation 9 (1990), the four orbit classes and exact multiplicities in equation (13), journal pp. 265--269; https://www.sciencedirect.com/science/article/pii/S0747717108800132