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Diff — Lie algebra

Revision #2289 → #2933 · back to history

modifiedCommutator Lie algebra from an associative algebra0460518f321a
FieldFrom #2289To #2933
noteAn associative algebra is given a Lie algebra instance via the ring commutator bracket.`LieAlgebra.ofAssociativeAlgebra` gives every associative algebra a Lie algebra instance via the ring commutator.
modifiedFundamental example: linear maps of a vector space7359f01f0832
FieldFrom #2289To #2933
note`Module.End R V` is a ring, hence a Lie algebra via the commutator instance.`Module.End R V` is a ring, hence a Lie algebra via the `LieRing.ofAssociativeRing`/`LieAlgebra.ofAssociativeAlgebra` commutator instance.
addedJacobi identityfcffee2661d8
modifiedCartan subalgebra7d9c2404c8f2
FieldFrom #2289To #2933
note`IsCartanSubalgebra` is a nilpotent, self-normalizing Lie subalgebra in Mathlib.`LieSubalgebra.IsCartanSubalgebra` is a nilpotent, self-normalizing Lie subalgebra in Mathlib.
addedsl₂ triple43221de85f80
modifiedCartan's criterion for solvabilityfa4c328d976a
FieldFrom #2289To #2933
mathlib.declLieAlgebra.isSolvable_of_killingForm_apply_lie_eq_zero
mathlib.match_kindspecial_case
mathlib.moduleMathlib.Algebra.Lie.CartanCriterion
noteThe solvability half of Cartan's criterion (Killing form vanishes on [L,L]) is not formalized.The `Killing form vanishes on [L,L] ⟹ L solvable` direction is formalized (in char 0); the converse is an explicit TODO in the file.
statusnot_formalizedpartial