OAI/Algebra/Finitistic/Encoding/QuadraticCoefficients.lean
8 declarations, 0 contain sorry, 0 declared as axioms
- abbrev
OAI.LittleFinitistic.QuadraticPresentation.Termline 10 - def
OAI.LittleFinitistic.QuadraticPresentation.termline 12 - theorem
OAI.LittleFinitistic.QuadraticPresentation.degreeLE_two_eq_spanline 19Source documentation
The degree bound is exactly the span of constants, generators, and ordered products of two generators. The two factors are never commuted.
theorem degreeLE_two_eq_span : degreeLE R α 2 = Submodule.span R (Set.range (term R α)) := by …Mentions: OAI.LittleFinitistic.QuadraticPresentation.degreeLE, OAI.LittleFinitistic.QuadraticPresentation.term
- def
OAI.LittleFinitistic.QuadraticPresentation.coefficientPolynomialline 42Source documentation
Finite coefficient form, suitable for the source's homogenization rule.
def coefficientPolynomial [Fintype α] (c : R) (l : α → R) (q : α → α → R) : FreeAlgebra R α := … - theorem
OAI.LittleFinitistic.QuadraticPresentation.exists_coefficientsline 48 - theorem
OAI.LittleFinitistic.QuadraticPresentation.coefficientPolynomial_degreeline 58 - theorem
OAI.LittleFinitistic.QuadraticPresentation.degreeLE_two_iff_coefficientsline 71Source documentation
An exact characterization; the degree predicate hides no higher terms.
theorem degreeLE_two_iff_coefficients [Fintype α] (p : FreeAlgebra R α) : p ∈ degreeLE R α 2 ↔ ∃ (c : R) (l : α → R) (q : α → α → R), coefficientPolynomial R α c l q = p := by …Mentions: OAI.LittleFinitistic.QuadraticPresentation.degreeLE, OAI.LittleFinitistic.QuadraticPresentation.coefficientPolynomial
- theorem
OAI.LittleFinitistic.QuadraticPresentation.relation_coefficientsline 80Source documentation
Every new quadratic relation has explicit constant, linear, and ordered quadratic coefficients, with a simultaneous choice for the whole finite family.
theorem relation_coefficients [Finite α] {κ : Type*} (p : κ → FreeAlgebra R α) (N : ℕ) : letI := Fintype.ofFinite (Letter α N) …