@@ -26,7 +26,7 @@ In this file, we prove **Krull's principal ideal theorem** (also known as
2626 that: In a commutative Noetherian ring `R`, any prime ideal that is minimal over a principal ideal
2727 has height at most 1.
2828
29- * `Ideal.height_le_spanRank_toENat_of_mem_minimal_primes ` : This theorem is the
29+ * `Ideal.height_le_spanRank_toENat_of_mem_minimalPrimes ` : This theorem is the
3030 **Krull's height theorem** (also known as **Krullscher Höhensatz** ), which states that:
3131 In a commutative Noetherian ring `R`, any prime ideal that is minimal over an ideal generated by
3232 `n` elements has height at most `n`.
@@ -36,7 +36,7 @@ In this file, we prove **Krull's principal ideal theorem** (also known as
3636 a (finitely-generated) ideal is smaller than or equal to the minimum number of generators for
3737 this ideal.
3838
39- * `Ideal.height_le_iff_exists_minimal_primes ` : In a commutative Noetherian ring `R`, a prime ideal
39+ * `Ideal.height_le_iff_exists_minimalPrimes ` : In a commutative Noetherian ring `R`, a prime ideal
4040 `p` has height no greater than `n` if and only if it is a minimal ideal over some ideal generated
4141 by no more than `n` elements.
4242 -/
@@ -148,7 +148,7 @@ theorem Ideal.mem_minimalPrimes_span_of_mem_minimalPrimes_span_insert {q p : Ide
148148 rw [height_eq_primeHeight] at h
149149 have := (primeHeight_strict_mono h_lt).trans_le h
150150 rw [ENat.lt_one_iff_eq_zero, primeHeight_eq_zero_iff] at this
151- have := minimal_primes_comap_of_surjective hf this
151+ have := minimalPrimes_comap_of_surjective hf this
152152 rwa [comap_map_of_surjective f hf, ← RingHom.ker_eq_comap_bot,
153153 mk_ker, sup_eq_left.mpr hI'q] at this
154154 refine height_le_one_of_isPrincipal_of_mem_minimalPrimes ((span {x}).map f) (p.map f) ⟨⟨this,
@@ -167,7 +167,7 @@ open IsLocalRing in
167167/-- **Krull's height theorem** (also known as **Krullscher Höhensatz** ) :
168168 In a commutative Noetherian ring `R`, any prime ideal that is minimal over an ideal generated
169169 by `n` elements has height at most `n`. -/
170- nonrec lemma Ideal.height_le_spanRank_toENat_of_mem_minimal_primes
170+ nonrec lemma Ideal.height_le_spanRank_toENat_of_mem_minimalPrimes
171171 (I : Ideal R) (p : Ideal R) (hp : p ∈ I.minimalPrimes) :
172172 p.height ≤ I.spanRank.toENat := by
173173 classical
@@ -219,11 +219,14 @@ nonrec lemma Ideal.height_le_spanRank_toENat_of_mem_minimal_primes
219219 refine hspan.trans <| radical_mono ?_
220220 rw [← Set.union_singleton, span_union]
221221
222+ @ [deprecated (since := "2026-04-01" )] alias Ideal.height_le_spanRank_toENat_of_mem_minimal_primes :=
223+ Ideal.height_le_spanRank_toENat_of_mem_minimalPrimes
224+
222225lemma Ideal.height_le_card_of_mem_minimalPrimes_span_finset {p : Ideal R} {s : Finset R}
223226 (hI : p ∈ (Ideal.span s).minimalPrimes) :
224227 p.height ≤ s.card := by
225228 trans (Cardinal.toENat (Submodule.spanRank (Ideal.span (s : Set R))))
226- · exact Ideal.height_le_spanRank_toENat_of_mem_minimal_primes _ _ hI
229+ · exact Ideal.height_le_spanRank_toENat_of_mem_minimalPrimes _ _ hI
227230 · simpa using Submodule.spanRank_span_le_card (s : Set R)
228231
229232lemma Ideal.height_le_card_of_mem_minimalPrimes_span {p : Ideal R} {s : Set R}
@@ -238,7 +241,7 @@ lemma Ideal.height_le_spanRank_toENat (I : Ideal R) (hI : I ≠ ⊤) :
238241 I.height ≤ I.spanRank.toENat := by
239242 obtain ⟨J, hJ⟩ := nonempty_minimalPrimes hI
240243 refine (iInf₂_le J hJ).trans ?_
241- convert (I.height_le_spanRank_toENat_of_mem_minimal_primes J hJ)
244+ convert (I.height_le_spanRank_toENat_of_mem_minimalPrimes J hJ)
242245 exact Eq.symm (@height_eq_primeHeight _ _ J hJ.1 .1 )
243246
244247lemma Ideal.height_le_spanFinrank (I : Ideal R) (hI : I ≠ ⊤) :
@@ -291,7 +294,7 @@ lemma Ideal.height_le_iff_exists_minimalPrimes (p : Ideal R) [p.IsPrime]
291294 norm_cast
292295 · rintro ⟨I, hp, hI⟩
293296 exact le_trans
294- (Ideal.height_le_spanRank_toENat_of_mem_minimal_primes I p hp)
297+ (Ideal.height_le_spanRank_toENat_of_mem_minimalPrimes I p hp)
295298 (by simpa using (Cardinal.toENat.monotone' hI))
296299
297300/-- If `p` is a prime in a Noetherian ring `R`, there exists a `p`-primary ideal `I`
@@ -308,7 +311,7 @@ lemma Ideal.exists_finset_card_eq_height_of_isNoetherianRing (p : Ideal R) [p.Is
308311 · convert_to p.height ≤ I.spanRank.toENat
309312 · symm
310313 simpa [Submodule.fg_iff_spanRank_eq_spanFinrank] using (IsNoetherian.noetherian I)
311- · exact I.height_le_spanRank_toENat_of_mem_minimal_primes _ hI
314+ · exact I.height_le_spanRank_toENat_of_mem_minimalPrimes _ hI
312315
313316/-- If `I ≤ p` and `p` is prime, the height of `p` is bounded by the height of `p ⧸ I R` plus
314317the span rank of `I`. -/
0 commit comments