Proof of `Exact-image bounds for independent affine columns` (2nd statement)
groundedproofs/Lax342547Proofs/AffineImages.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
A left inverse of the nominal coefficient matrix lifts any T-tuple of common-subspace vectors to the allowed column spaces. Thus the image contains an injective copy of the full T-fold common subspace.