Proof of `Rank of a tensor killed in two quotient spaces` (2nd statement)
groundedproofs/Lax342547Proofs/QuotientRank.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
Apply the linear-map bound to the matrix sandwich. Rank-nullity and invariance under transpose identify its right loss with the second kernel.