Homomorphism polynomials span matrix-symmetric polynomials
Lax461425.HomomorphismSpanning · concepts/Lax461425/HomomorphismSpanning.lean · lax-461425
No public endorsements yet.
Loading review…
Sign in with ORCIDNatural Language Statement
Theorem
Over a field of characteristic zero, every matrix-symmetric polynomial in an matrix, for , is a finite linear combination of homomorphism polynomials of bipartite multigraph patterns having at most vertices on each side.
Concept map
Evidence
Each proof establishes this claim relative to its assumptions.
Lean source view on GitHub
| 1 | import Lax461425.SymmetricFamilies |
| 2 | import Lax461425.HomomorphismPolynomials |
| 3 | import Mathlib.LinearAlgebra.Span.Defs |
| 4 | |
| 5 | /-! |
| 6 | --- |
| 7 | title: Homomorphism polynomials span matrix-symmetric polynomials |
| 8 | type: theorem |
| 9 | --- |
| 10 | Over a field of characteristic zero, every matrix-symmetric polynomial in an `n × n` |
| 11 | matrix, for `n ≥ 1`, is a finite linear combination of homomorphism polynomials of |
| 12 | bipartite multigraph patterns having at most `n` vertices on each side. |
| 13 | -/ |
| 14 | |
| 15 | namespace Lax461425.HomomorphismSpanning |
| 16 | |
| 17 | open SymmetricFamilies HomomorphismPolynomials |
| 18 | |
| 19 | /-- Matrix-invariant polynomials are linear combinations of homomorphism polynomials of |
| 20 | patterns with at most `n` vertices on each side. -/ |
| 21 | axiom invariant_mem_span_hom {K : Type*} [Field K] [CharZero K] {n : ℕ} |
| 22 | (hn : 1 ≤ n) (p : MatrixPolynomial n K) (hp : MatrixInvariant p) : |
| 23 | p ∈ Submodule.span K {q | ∃ F : Pattern, |
| 24 | Fintype.card F.A ≤ n ∧ Fintype.card F.B ≤ n ∧ hom K F n = q} |
| 25 | |
| 26 | end Lax461425.HomomorphismSpanning |
| 27 |
Discussion
Ask a question or add context. Endorsements and structured flags are kept in the review panel above.
0 comments