English
If M is reflexive, then a linear equivalence e: N ≃ Dual M yields a perfect pairing between N and M.
Русский
Если M рефлексивен, то линейное эквивалентное отображение e: N ≃ Dual M задаёт идеальную пару между N и M.
LaTeX
$$$\text{ToPerfectPairing}(e): \text{PerfectPairing } R\,N\,M$.$$
Lean4
/-- A reflexive module has a perfect pairing with its dual. -/
@[deprecated LinearMap.IsPerfPair.id (since := "2025-05-27")]
def toPerfectPairingDual : PerfectPairing R (Dual R M) M
where
toLinearMap := .id
bijective_left := bijective_id
bijective_right := bijective_dual_eval R M