Supporting results for pointwise provable equality.
Composition descends to the quotient by the generated congruence. The PA proofs of associativity and the identity laws make this quotient a monoid for every theory extending PA. A universal congruence gives a singleton quotient.
def
PointwiseComposition.FailureOfComposition.GeneratedCongruence.QuotientGraph
(T : FFL.FirstOrder.ArithmeticTheory)
:
PA-functional Sigma-one graphs modulo the generated composition congruence.
Equations
Instances For
def
PointwiseComposition.FailureOfComposition.GeneratedCongruence.quotientMk
(T : FFL.FirstOrder.ArithmeticTheory)
(F : ProofSearch.FunctionalGraph)
:
The class of a functional graph.
Instances For
@[instance_reducible]
instance
PointwiseComposition.FailureOfComposition.GeneratedCongruence.instMulQuotientGraph
(T : FFL.FirstOrder.ArithmeticTheory)
:
Mul (QuotientGraph T)
Equations
- One or more equations did not get rendered due to their size.
@[instance_reducible]
@[simp]
theorem
PointwiseComposition.FailureOfComposition.GeneratedCongruence.comp_associative_uniform
(F G H : ProofSearch.Graph)
:
ProofSearch.Uniform 𝐏𝐀 (ProofSearch.comp (ProofSearch.comp F G) H) (ProofSearch.comp F (ProofSearch.comp G H))
Composition of graph formulas is associative already in PA.
@[instance_reducible]
instance
PointwiseComposition.FailureOfComposition.GeneratedCongruence.quotientMonoid
(T : FFL.FirstOrder.ArithmeticTheory)
[𝐏𝐀 ≼ T]
:
Monoid (QuotientGraph T)
Equations
- One or more equations did not get rendered due to their size.
theorem
PointwiseComposition.FailureOfComposition.GeneratedCongruence.quotient_subsingleton_of_universal
(T : FFL.FirstOrder.ArithmeticTheory)
(h : ∀ (F G : ProofSearch.FunctionalGraph), Rel T F G)
:
If all functional graphs are related, every two quotient elements are equal. Together with the identity element, this makes the quotient a singleton.