English
Under Module.Finite, IsFinitelySemisimple is equivalent to IsSemisimple (variant variant).
Русский
При Module.Finite IsFinitelySemisimple эквивалентно IsSemisimple.
LaTeX
$$$ [Module.Finite R M] \Rightarrow (IsFinitelySemisimple(f) \iff IsSemisimple(f))$$$
Lean4
@[simp]
theorem isFinitelySemisimple_iff_isSemisimple [Module.Finite R M] : f.IsFinitelySemisimple ↔ f.IsSemisimple :=
by
refine ⟨fun hf ↦ isSemisimple_iff.mpr fun p hp ↦ ?_, IsSemisimple.isFinitelySemisimple⟩
obtain ⟨q, -, hq₁, hq₂, hq₃⟩ := isFinitelySemisimple_iff.mp hf ⊤ (invtSubmodule.top_mem f) inferInstance p hp le_top
exact ⟨q, hq₁, hq₂, codisjoint_iff.mpr hq₃⟩