English
The span of nonzero weights images equals the top submodule in the dual.
Русский
Образ ненулевых весов образует единичное подполье двойственного пространства.
LaTeX
$$$ span K (\\{ α \\mid α.IsNonZero \\}.image (Weight.toLinear K H L)) = \\top $$$
Lean4
/-- Given a splitting Cartan subalgebra `H` of a finite-dimensional Lie algebra with non-singular
Killing form, the corresponding roots span the dual space of `H`. -/
@[simp]
theorem span_weight_eq_top : span K (range (Weight.toLinear K H L)) = ⊤ :=
by
refine eq_top_iff.mpr (le_trans ?_ (LieModule.range_traceForm_le_span_weight K H L))
rw [← traceForm_flip K H L, ← LinearMap.dualAnnihilator_ker_eq_range_flip, ker_traceForm_eq_bot_of_isCartanSubalgebra,
Submodule.dualAnnihilator_bot]