Proof of `Polar rank of the formal mixer quadratic` (3rd statement)
groundedproofs/Lax342547Proofs/FormalQuadratic.lean · lax-342547
What this proof establishes
no assumptions
Assuming the claims on the left, the claim on the right holds — checked by the archive's pipeline. Proof code is not displayed here.
Description
Test one half of one formal block at a time. Nonsingularity of the middle form forces both coordinates of every radical vector to vanish. Thus the polar map is injective and its rank is the full row dimension.