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Theorems · Theorem · ring theory

exists_isIdempotentElem_mul_eq_zero_of_ker_isNilpotent

∀ {R : Type u_1} {S : Type u_2} [inst : Ring R] [inst_1 : Ring S] (f : R →+* S),
  (∀ x ∈ RingHom.ker f, IsNilpotent x) →
    ∀ e₁ ∈ f.range,
      IsIdempotentElem e₁ →
        ∀ (e₂ : R),
          IsIdempotentElem e₂ →
            e₁ * f e₂ = 0 → f e₂ * e₁ = 0 → ∃ e', IsIdempotentElem e' ∧ f e' = e₁ ∧ e' * e₂ = 0 ∧ e₂ * e' = 0

Orthogonal idempotents lift along nil ideals.

Defined in
Mathlib.RingTheory.Idempotents
Cited by
2 results in Mathlib
Foundations
Depth 85 from the axioms · uses propext, Classical.choice, Quot.sound
Assumes
RingRing

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