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chore: generalise lemmas to ENorm spaces, part 1 (#21380)
Extracted from #21375: these lemmas only change the assumption on the co-domain, but not any hypothesis. This continues the work started in #20121, #20122 and #21306: those PRs generalised the definitions resp. made lemma statements use the enorm. This PR starts generalising the lemmas using those definitions. This work is part of (and a necessary pre-requisite for) the Carleson project.
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Mathlib/Analysis/NormedSpace/IndicatorFunction.lean

Lines changed: 14 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -7,9 +7,9 @@ import Mathlib.Algebra.Order.Group.Indicator
77
import Mathlib.Analysis.Normed.Group.Basic
88

99
/-!
10-
# Indicator function and norm
10+
# Indicator function and (e)norm
1111
12-
This file contains a few simple lemmas about `Set.indicator` and `norm`.
12+
This file contains a few simple lemmas about `Set.indicator`, `norm` and `enorm`.
1313
1414
## Tags
1515
indicator, norm
@@ -36,9 +36,21 @@ theorem norm_indicator_le_of_subset (h : s ⊆ t) (f : α → E) (a : α) :
3636
simp only [norm_indicator_eq_indicator_norm]
3737
exact indicator_le_indicator_of_subset ‹_› (fun _ => norm_nonneg _) _
3838

39+
theorem enorm_indicator_le_of_subset (h : s ⊆ t) (f : α → E) (a : α) :
40+
‖indicator s f a‖ₑ ≤ ‖indicator t f a‖ₑ := by
41+
simp only [enorm_indicator_eq_indicator_enorm]
42+
apply indicator_le_indicator_of_subset ‹_› (zero_le _)
43+
3944
theorem indicator_norm_le_norm_self : indicator s (fun a => ‖f a‖) a ≤ ‖f a‖ :=
4045
indicator_le_self' (fun _ _ => norm_nonneg _) a
4146

47+
theorem indicator_enorm_le_enorm_self : indicator s (fun a => ‖f a‖ₑ) a ≤ ‖f a‖ₑ :=
48+
indicator_le_self' (fun _ _ ↦ zero_le _) a
49+
4250
theorem norm_indicator_le_norm_self : ‖indicator s f a‖ ≤ ‖f a‖ := by
4351
rw [norm_indicator_eq_indicator_norm]
4452
apply indicator_norm_le_norm_self
53+
54+
theorem enorm_indicator_le_enorm_self : ‖indicator s f a‖ₑ ≤ ‖f a‖ₑ := by
55+
rw [enorm_indicator_eq_indicator_enorm]
56+
apply indicator_enorm_le_enorm_self

Mathlib/MeasureTheory/Function/L2Space.lean

Lines changed: 1 addition & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -20,10 +20,8 @@ is also an inner product space, with inner product defined as `inner f g = ∫ a
2020
* `integrable_inner` : for `f` and `g` in `Lp E 2 μ`, the pointwise inner product
2121
`fun x ↦ ⟪f x, g x⟫` is integrable.
2222
* `L2.innerProductSpace` : `Lp E 2 μ` is an inner product space.
23-
2423
-/
2524

26-
2725
noncomputable section
2826

2927
open TopologicalSpace MeasureTheory MeasureTheory.Lp Filter
@@ -160,7 +158,7 @@ private theorem norm_sq_eq_inner' (f : α →₂[μ] E) : ‖f‖ ^ 2 = RCLike.r
160158
· rw [← ENNReal.rpow_natCast, eLpNorm_eq_eLpNorm' two_ne_zero ENNReal.ofNat_ne_top, eLpNorm', ←
161159
ENNReal.rpow_mul, one_div, h_two]
162160
simp [enorm_eq_nnnorm]
163-
· refine (lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top zero_lt_two ?_).ne
161+
· refine (lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top zero_lt_two (ε := E) ?_).ne
164162
rw [← h_two, ← eLpNorm_eq_eLpNorm' two_ne_zero ENNReal.ofNat_ne_top]
165163
exact Lp.eLpNorm_lt_top f
166164

Mathlib/MeasureTheory/Function/LpSeminorm/Basic.lean

Lines changed: 51 additions & 44 deletions
Original file line numberDiff line numberDiff line change
@@ -70,7 +70,7 @@ this quantity is finite -/
7070
def eLpNorm' {_ : MeasurableSpace α} (f : α → ε) (q : ℝ) (μ : Measure α) : ℝ≥0∞ :=
7171
(∫⁻ a, ‖f a‖ₑ ^ q ∂μ) ^ (1 / q)
7272

73-
lemma eLpNorm'_eq_lintegral_enorm {_ : MeasurableSpace α} (f : α → F) (q : ℝ) (μ : Measure α) :
73+
lemma eLpNorm'_eq_lintegral_enorm {_ : MeasurableSpace α} (f : α → ε) (q : ℝ) (μ : Measure α) :
7474
eLpNorm' f q μ = (∫⁻ a, ‖f a‖ₑ ^ q ∂μ) ^ (1 / q) :=
7575
rfl
7676

@@ -81,7 +81,7 @@ alias eLpNorm'_eq_lintegral_nnnorm := eLpNorm'_eq_lintegral_enorm
8181
def eLpNormEssSup {_ : MeasurableSpace α} (f : α → ε) (μ : Measure α) :=
8282
essSup (fun x => ‖f x‖ₑ) μ
8383

84-
lemma eLpNormEssSup_eq_essSup_enorm {_ : MeasurableSpace α} (f : α → F) (μ : Measure α) :
84+
lemma eLpNormEssSup_eq_essSup_enorm {_ : MeasurableSpace α} (f : α → ε) (μ : Measure α) :
8585
eLpNormEssSup f μ = essSup (‖f ·‖ₑ) μ := rfl
8686

8787
@[deprecated (since := "2025-01-17")]
@@ -93,53 +93,53 @@ def eLpNorm {_ : MeasurableSpace α}
9393
(f : α → ε) (p : ℝ≥0∞) (μ : Measure α := by volume_tac) : ℝ≥0∞ :=
9494
if p = 0 then 0 else if p = ∞ then eLpNormEssSup f μ else eLpNorm' f (ENNReal.toReal p) μ
9595

96-
theorem eLpNorm_eq_eLpNorm' (hp_ne_zero : p ≠ 0) (hp_ne_top : p ≠ ∞) {f : α → F} :
96+
theorem eLpNorm_eq_eLpNorm' (hp_ne_zero : p ≠ 0) (hp_ne_top : p ≠ ∞) {f : α → ε} :
9797
eLpNorm f p μ = eLpNorm' f (ENNReal.toReal p) μ := by simp [eLpNorm, hp_ne_zero, hp_ne_top]
9898

99-
lemma eLpNorm_nnreal_eq_eLpNorm' {f : α → F} {p : ℝ≥0} (hp : p ≠ 0) :
99+
lemma eLpNorm_nnreal_eq_eLpNorm' {f : α → ε} {p : ℝ≥0} (hp : p ≠ 0) :
100100
eLpNorm f p μ = eLpNorm' f p μ :=
101101
eLpNorm_eq_eLpNorm' (by exact_mod_cast hp) ENNReal.coe_ne_top
102102

103-
theorem eLpNorm_eq_lintegral_rpow_enorm (hp_ne_zero : p ≠ 0) (hp_ne_top : p ≠ ∞) {f : α → F} :
103+
theorem eLpNorm_eq_lintegral_rpow_enorm (hp_ne_zero : p ≠ 0) (hp_ne_top : p ≠ ∞) {f : α → ε} :
104104
eLpNorm f p μ = (∫⁻ x, ‖f x‖ₑ ^ p.toReal ∂μ) ^ (1 / p.toReal) := by
105105
rw [eLpNorm_eq_eLpNorm' hp_ne_zero hp_ne_top, eLpNorm'_eq_lintegral_enorm]
106106

107107
@[deprecated (since := "2025-01-17")]
108108
alias eLpNorm_eq_lintegral_rpow_nnnorm := eLpNorm_eq_lintegral_rpow_enorm
109109

110-
lemma eLpNorm_nnreal_eq_lintegral {f : α → F} {p : ℝ≥0} (hp : p ≠ 0) :
110+
lemma eLpNorm_nnreal_eq_lintegral {f : α → ε} {p : ℝ≥0} (hp : p ≠ 0) :
111111
eLpNorm f p μ = (∫⁻ x, ‖f x‖ₑ ^ (p : ℝ) ∂μ) ^ (1 / (p : ℝ)) :=
112112
eLpNorm_nnreal_eq_eLpNorm' hp
113113

114-
theorem eLpNorm_one_eq_lintegral_enorm {f : α → F} : eLpNorm f 1 μ = ∫⁻ x, ‖f x‖ₑ ∂μ := by
114+
theorem eLpNorm_one_eq_lintegral_enorm {f : α → ε} : eLpNorm f 1 μ = ∫⁻ x, ‖f x‖ₑ ∂μ := by
115115
simp_rw [eLpNorm_eq_lintegral_rpow_enorm one_ne_zero ENNReal.coe_ne_top, ENNReal.one_toReal,
116116
one_div_one, ENNReal.rpow_one]
117117

118118
@[deprecated (since := "2025-01-17")]
119119
alias eLpNorm_one_eq_lintegral_nnnorm := eLpNorm_one_eq_lintegral_enorm
120120

121121
@[simp]
122-
theorem eLpNorm_exponent_top {f : α → F} : eLpNorm f ∞ μ = eLpNormEssSup f μ := by simp [eLpNorm]
122+
theorem eLpNorm_exponent_top {f : α → ε} : eLpNorm f ∞ μ = eLpNormEssSup f μ := by simp [eLpNorm]
123123

124124
/-- The property that `f:α→E` is ae strongly measurable and `(∫ ‖f a‖^p ∂μ)^(1/p)` is finite
125125
if `p < ∞`, or `essSup f < ∞` if `p = ∞`. -/
126126
def Memℒp {α} {_ : MeasurableSpace α} [TopologicalSpace ε] (f : α → ε) (p : ℝ≥0∞)
127127
(μ : Measure α := by volume_tac) : Prop :=
128128
AEStronglyMeasurable f μ ∧ eLpNorm f p μ < ∞
129129

130-
theorem Memℒp.aestronglyMeasurable {f : α → E} {p : ℝ≥0∞} (h : Memℒp f p μ) :
130+
theorem Memℒp.aestronglyMeasurable [TopologicalSpace ε] {f : α → ε} {p : ℝ≥0∞} (h : Memℒp f p μ) :
131131
AEStronglyMeasurable f μ :=
132132
h.1
133133

134-
theorem lintegral_rpow_enorm_eq_rpow_eLpNorm' {f : α → F} (hq0_lt : 0 < q) :
134+
theorem lintegral_rpow_enorm_eq_rpow_eLpNorm' {f : α → ε} (hq0_lt : 0 < q) :
135135
∫⁻ a, ‖f a‖ₑ ^ q ∂μ = eLpNorm' f q μ ^ q := by
136136
rw [eLpNorm'_eq_lintegral_enorm, ← ENNReal.rpow_mul, one_div, inv_mul_cancel₀, ENNReal.rpow_one]
137137
exact hq0_lt.ne'
138138

139139
@[deprecated (since := "2025-01-17")]
140140
alias lintegral_rpow_nnnorm_eq_rpow_eLpNorm' := lintegral_rpow_enorm_eq_rpow_eLpNorm'
141141

142-
lemma eLpNorm_nnreal_pow_eq_lintegral {f : α → F} {p : ℝ≥0} (hp : p ≠ 0) :
142+
lemma eLpNorm_nnreal_pow_eq_lintegral {f : α → ε} {p : ℝ≥0} (hp : p ≠ 0) :
143143
eLpNorm f p μ ^ (p : ℝ) = ∫⁻ x, ‖f x‖ₑ ^ (p : ℝ) ∂μ := by
144144
simp [eLpNorm_eq_eLpNorm' (by exact_mod_cast hp) ENNReal.coe_ne_top,
145145
lintegral_rpow_enorm_eq_rpow_eLpNorm' ((NNReal.coe_pos.trans pos_iff_ne_zero).mpr hp)]
@@ -148,13 +148,15 @@ end ℒpSpaceDefinition
148148

149149
section Top
150150

151-
theorem Memℒp.eLpNorm_lt_top {f : α → E} (hfp : Memℒp f p μ) : eLpNorm f p μ < ∞ :=
151+
theorem Memℒp.eLpNorm_lt_top [TopologicalSpace ε] {f : α → ε} (hfp : Memℒp f p μ) :
152+
eLpNorm f p μ < ∞ :=
152153
hfp.2
153154

154-
theorem Memℒp.eLpNorm_ne_top {f : α → E} (hfp : Memℒp f p μ) : eLpNorm f p μ ≠ ∞ :=
155+
theorem Memℒp.eLpNorm_ne_top [TopologicalSpace ε] {f : α → ε} (hfp : Memℒp f p μ) :
156+
eLpNorm f p μ ≠ ∞ :=
155157
ne_of_lt hfp.2
156158

157-
theorem lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top {f : α → F} (hq0_lt : 0 < q)
159+
theorem lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top {f : α → ε} (hq0_lt : 0 < q)
158160
(hfq : eLpNorm' f q μ < ∞) : ∫⁻ a, ‖f a‖ₑ ^ q ∂μ < ∞ := by
159161
rw [lintegral_rpow_enorm_eq_rpow_eLpNorm' hq0_lt]
160162
exact ENNReal.rpow_lt_top_of_nonneg (le_of_lt hq0_lt) (ne_of_lt hfq)
@@ -163,7 +165,7 @@ theorem lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top {f : α → F} (hq0_lt :
163165
alias lintegral_rpow_nnnorm_lt_top_of_eLpNorm'_lt_top' :=
164166
lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top
165167

166-
theorem lintegral_rpow_enorm_lt_top_of_eLpNorm_lt_top {f : α → F} (hp_ne_zero : p ≠ 0)
168+
theorem lintegral_rpow_enorm_lt_top_of_eLpNorm_lt_top {f : α → ε} (hp_ne_zero : p ≠ 0)
167169
(hp_ne_top : p ≠ ∞) (hfp : eLpNorm f p μ < ∞) : ∫⁻ a, ‖f a‖ₑ ^ p.toReal ∂μ < ∞ := by
168170
apply lintegral_rpow_enorm_lt_top_of_eLpNorm'_lt_top
169171
· exact ENNReal.toReal_pos hp_ne_zero hp_ne_top
@@ -173,7 +175,7 @@ theorem lintegral_rpow_enorm_lt_top_of_eLpNorm_lt_top {f : α → F} (hp_ne_zero
173175
alias lintegral_rpow_nnnorm_lt_top_of_eLpNorm_lt_top :=
174176
lintegral_rpow_enorm_lt_top_of_eLpNorm_lt_top
175177

176-
theorem eLpNorm_lt_top_iff_lintegral_rpow_nnnorm_lt_top {f : α → F} (hp_ne_zero : p ≠ 0)
178+
theorem eLpNorm_lt_top_iff_lintegral_rpow_nnnorm_lt_top {f : α → ε} (hp_ne_zero : p ≠ 0)
177179
(hp_ne_top : p ≠ ∞) : eLpNorm f p μ < ∞ ↔ ∫⁻ a, (‖f a‖ₑ) ^ p.toReal ∂μ < ∞ :=
178180
⟨lintegral_rpow_enorm_lt_top_of_eLpNorm_lt_top hp_ne_zero hp_ne_top, by
179181
intro h
@@ -187,14 +189,14 @@ end Top
187189
section Zero
188190

189191
@[simp]
190-
theorem eLpNorm'_exponent_zero {f : α → F} : eLpNorm' f 0 μ = 1 := by
192+
theorem eLpNorm'_exponent_zero {f : α → ε} : eLpNorm' f 0 μ = 1 := by
191193
rw [eLpNorm', div_zero, ENNReal.rpow_zero]
192194

193195
@[simp]
194-
theorem eLpNorm_exponent_zero {f : α → F} : eLpNorm f 0 μ = 0 := by simp [eLpNorm]
196+
theorem eLpNorm_exponent_zero {f : α → ε} : eLpNorm f 0 μ = 0 := by simp [eLpNorm]
195197

196198
@[simp]
197-
theorem memℒp_zero_iff_aestronglyMeasurable {f : α → E} :
199+
theorem memℒp_zero_iff_aestronglyMeasurable [TopologicalSpace ε] {f : α → ε} :
198200
Memℒp f 0 μ ↔ AEStronglyMeasurable f μ := by simp [Memℒp, eLpNorm_exponent_zero]
199201

200202
@[simp]
@@ -233,29 +235,30 @@ theorem eLpNorm_zero' : eLpNorm (fun _ : α => (0 : F)) p μ = 0 := by convert e
233235

234236
variable [MeasurableSpace α]
235237

236-
theorem eLpNorm'_measure_zero_of_pos {f : α → F} (hq_pos : 0 < q) :
238+
theorem eLpNorm'_measure_zero_of_pos {f : α → ε} (hq_pos : 0 < q) :
237239
eLpNorm' f q (0 : Measure α) = 0 := by simp [eLpNorm', hq_pos]
238240

239-
theorem eLpNorm'_measure_zero_of_exponent_zero {f : α → F} : eLpNorm' f 0 (0 : Measure α) = 1 := by
241+
theorem eLpNorm'_measure_zero_of_exponent_zero {f : α → ε} : eLpNorm' f 0 (0 : Measure α) = 1 := by
240242
simp [eLpNorm']
241243

242-
theorem eLpNorm'_measure_zero_of_neg {f : α → F} (hq_neg : q < 0) :
244+
theorem eLpNorm'_measure_zero_of_neg {f : α → ε} (hq_neg : q < 0) :
243245
eLpNorm' f q (0 : Measure α) = ∞ := by simp [eLpNorm', hq_neg]
244246

245247
@[simp]
246-
theorem eLpNormEssSup_measure_zero {f : α → F} : eLpNormEssSup f (0 : Measure α) = 0 := by
248+
theorem eLpNormEssSup_measure_zero {f : α → ε} : eLpNormEssSup f (0 : Measure α) = 0 := by
247249
simp [eLpNormEssSup]
248250

249251
@[simp]
250-
theorem eLpNorm_measure_zero {f : α → F} : eLpNorm f p (0 : Measure α) = 0 := by
252+
theorem eLpNorm_measure_zero {f : α → ε} : eLpNorm f p (0 : Measure α) = 0 := by
251253
by_cases h0 : p = 0
252254
· simp [h0]
253255
by_cases h_top : p = ∞
254256
· simp [h_top]
255257
rw [← Ne] at h0
256258
simp [eLpNorm_eq_eLpNorm' h0 h_top, eLpNorm', ENNReal.toReal_pos h0 h_top]
257259

258-
@[simp] lemma memℒp_measure_zero {f : α → F} : Memℒp f p (0 : Measure α) := by simp [Memℒp]
260+
@[simp] lemma memℒp_measure_zero [TopologicalSpace ε] {f : α → ε} : Memℒp f p (0 : Measure α) := by
261+
simp [Memℒp]
259262

260263
end Zero
261264

@@ -286,7 +289,7 @@ end Neg
286289

287290
section Const
288291

289-
theorem eLpNorm'_const (c : F) (hq_pos : 0 < q) :
292+
theorem eLpNorm'_const (c : ε) (hq_pos : 0 < q) :
290293
eLpNorm' (fun _ : α => c) q μ = ‖c‖ₑ * μ Set.univ ^ (1 / q) := by
291294
rw [eLpNorm'_eq_lintegral_enorm, lintegral_const,
292295
ENNReal.mul_rpow_of_nonneg _ _ (by simp [hq_pos.le] : 01 / q)]
@@ -306,19 +309,19 @@ theorem eLpNorm'_const' [IsFiniteMeasure μ] (c : F) (hc_ne_zero : c ≠ 0) (hq_
306309
· rw [Ne, ENNReal.rpow_eq_top_iff, not_or, not_and_or, not_and_or]
307310
simp [hc_ne_zero]
308311

309-
theorem eLpNormEssSup_const (c : F) (hμ : μ ≠ 0) : eLpNormEssSup (fun _ : α => c) μ = ‖c‖ₑ := by
312+
theorem eLpNormEssSup_const (c : ε) (hμ : μ ≠ 0) : eLpNormEssSup (fun _ : α => c) μ = ‖c‖ₑ := by
310313
rw [eLpNormEssSup_eq_essSup_enorm, essSup_const _ hμ]
311314

312-
theorem eLpNorm'_const_of_isProbabilityMeasure (c : F) (hq_pos : 0 < q) [IsProbabilityMeasure μ] :
315+
theorem eLpNorm'_const_of_isProbabilityMeasure (c : ε) (hq_pos : 0 < q) [IsProbabilityMeasure μ] :
313316
eLpNorm' (fun _ : α => c) q μ = ‖c‖ₑ := by simp [eLpNorm'_const c hq_pos, measure_univ]
314317

315-
theorem eLpNorm_const (c : F) (h0 : p ≠ 0) (hμ : μ ≠ 0) :
318+
theorem eLpNorm_const (c : ε) (h0 : p ≠ 0) (hμ : μ ≠ 0) :
316319
eLpNorm (fun _ : α => c) p μ = ‖c‖ₑ * μ Set.univ ^ (1 / ENNReal.toReal p) := by
317320
by_cases h_top : p = ∞
318321
· simp [h_top, eLpNormEssSup_const c hμ]
319322
simp [eLpNorm_eq_eLpNorm' h0 h_top, eLpNorm'_const, ENNReal.toReal_pos h0 h_top]
320323

321-
theorem eLpNorm_const' (c : F) (h0 : p ≠ 0) (h_top : p ≠ ∞) :
324+
theorem eLpNorm_const' (c : ε) (h0 : p ≠ 0) (h_top : p ≠ ∞) :
322325
eLpNorm (fun _ : α => c) p μ = ‖c‖ₑ * μ Set.univ ^ (1 / ENNReal.toReal p) := by
323326
simp [eLpNorm_eq_eLpNorm' h0 h_top, eLpNorm'_const, ENNReal.toReal_pos h0 h_top]
324327

@@ -552,32 +555,33 @@ theorem memℒp_of_bounded [IsFiniteMeasure μ]
552555
(memℒp_const (max |a| |b|)).mono' hX (by filter_upwards [ha, hb] with x using abs_le_max_abs_abs)
553556

554557
@[gcongr, mono]
555-
theorem eLpNorm'_mono_measure (f : α → F) (hμν : ν ≤ μ) (hq : 0 ≤ q) :
558+
theorem eLpNorm'_mono_measure (f : α → ε) (hμν : ν ≤ μ) (hq : 0 ≤ q) :
556559
eLpNorm' f q ν ≤ eLpNorm' f q μ := by
557560
simp_rw [eLpNorm']
558561
gcongr
559562
exact lintegral_mono' hμν le_rfl
560563

561564
@[gcongr, mono]
562-
theorem eLpNormEssSup_mono_measure (f : α → F) (hμν : ν ≪ μ) :
565+
theorem eLpNormEssSup_mono_measure (f : α → ε) (hμν : ν ≪ μ) :
563566
eLpNormEssSup f ν ≤ eLpNormEssSup f μ := by
564567
simp_rw [eLpNormEssSup]
565568
exact essSup_mono_measure hμν
566569

567570
@[gcongr, mono]
568-
theorem eLpNorm_mono_measure (f : α → F) (hμν : ν ≤ μ) : eLpNorm f p ν ≤ eLpNorm f p μ := by
571+
theorem eLpNorm_mono_measure (f : α → ε) (hμν : ν ≤ μ) : eLpNorm f p ν ≤ eLpNorm f p μ := by
569572
by_cases hp0 : p = 0
570573
· simp [hp0]
571574
by_cases hp_top : p = ∞
572575
· simp [hp_top, eLpNormEssSup_mono_measure f (Measure.absolutelyContinuous_of_le hμν)]
573576
simp_rw [eLpNorm_eq_eLpNorm' hp0 hp_top]
574577
exact eLpNorm'_mono_measure f hμν ENNReal.toReal_nonneg
575578

576-
theorem Memℒp.mono_measure {f : α → E} (hμν : ν ≤ μ) (hf : Memℒp f p μ) : Memℒp f p ν :=
579+
theorem Memℒp.mono_measure [TopologicalSpace ε] {f : α → ε} (hμν : ν ≤ μ) (hf : Memℒp f p μ) :
580+
Memℒp f p ν :=
577581
⟨hf.1.mono_measure hμν, (eLpNorm_mono_measure f hμν).trans_lt hf.2
578582

579583
section Indicator
580-
variable {c : F} {hf : AEStronglyMeasurable f μ} {s : Set α}
584+
variable {c : ε} {hf : AEStronglyMeasurable f μ} {s : Set α}
581585

582586
lemma eLpNorm_indicator_eq_eLpNorm_restrict (hs : MeasurableSet s) :
583587
eLpNorm (s.indicator f) p μ = eLpNorm f p (μ.restrict s) := by
@@ -635,6 +639,9 @@ lemma eLpNormEssSup_indicator_const_eq (s : Set α) (c : G) (hμs : μ s ≠ 0)
635639
refine hμs (measure_mono_null (fun x hx_mem => ?_) h')
636640
rw [Set.mem_setOf_eq, Set.indicator_of_mem hx_mem, enorm_eq_nnnorm]
637641

642+
-- The following lemmas require [Zero F].
643+
variable {c : F}
644+
638645
lemma eLpNorm_indicator_const₀ (hs : NullMeasurableSet s μ) (hp : p ≠ 0) (hp_top : p ≠ ∞) :
639646
eLpNorm (s.indicator fun _ => c) p μ = ‖c‖ₑ * μ s ^ (1 / p.toReal) :=
640647
have hp_pos : 0 < p.toReal := ENNReal.toReal_pos hp hp_top
@@ -692,14 +699,14 @@ lemma memℒp_indicator_const (p : ℝ≥0∞) (hs : MeasurableSet s) (c : E) (h
692699
· have := Fact.mk hμ.lt_top
693700
apply memℒp_const
694701

695-
lemma eLpNormEssSup_piecewise (f g : α → E) [DecidablePred (· ∈ s)] (hs : MeasurableSet s) :
702+
lemma eLpNormEssSup_piecewise (f g : α → ε) [DecidablePred (· ∈ s)] (hs : MeasurableSet s) :
696703
eLpNormEssSup (Set.piecewise s f g) μ
697704
= max (eLpNormEssSup f (μ.restrict s)) (eLpNormEssSup g (μ.restrict sᶜ)) := by
698705
simp only [eLpNormEssSup, ← ENNReal.essSup_piecewise hs]
699706
congr with x
700707
by_cases hx : x ∈ s <;> simp [hx]
701708

702-
lemma eLpNorm_top_piecewise (f g : α → E) [DecidablePred (· ∈ s)] (hs : MeasurableSet s) :
709+
lemma eLpNorm_top_piecewise (f g : α → ε) [DecidablePred (· ∈ s)] (hs : MeasurableSet s) :
703710
eLpNorm (Set.piecewise s f g) ∞ μ
704711
= max (eLpNorm f ∞ (μ.restrict s)) (eLpNorm g ∞ (μ.restrict sᶜ)) :=
705712
eLpNormEssSup_piecewise f g hs
@@ -745,10 +752,11 @@ theorem eLpNorm_restrict_eq_of_support_subset {s : Set α} {f : α → F} (hsf :
745752
have : ¬(p.toReal ≤ 0) := by simpa only [not_le] using ENNReal.toReal_pos hp0 hp_top
746753
simpa [this] using hsf
747754

748-
theorem Memℒp.restrict (s : Set α) {f : α → E} (hf : Memℒp f p μ) : Memℒp f p (μ.restrict s) :=
755+
theorem Memℒp.restrict [TopologicalSpace ε] (s : Set α) {f : α → ε} (hf : Memℒp f p μ) :
756+
Memℒp f p (μ.restrict s) :=
749757
hf.mono_measure Measure.restrict_le_self
750758

751-
theorem eLpNorm'_smul_measure {p : ℝ} (hp : 0 ≤ p) {f : α → F} (c : ℝ≥0∞) :
759+
theorem eLpNorm'_smul_measure {p : ℝ} (hp : 0 ≤ p) {f : α → ε} (c : ℝ≥0∞) :
752760
eLpNorm' f p (c • μ) = c ^ (1 / p) * eLpNorm' f p μ := by
753761
rw [eLpNorm', lintegral_smul_measure, ENNReal.mul_rpow_of_nonneg, eLpNorm']
754762
simp [hp]
@@ -766,7 +774,7 @@ end SMul
766774

767775
/-- Use `eLpNorm_smul_measure_of_ne_top` instead. -/
768776
private theorem eLpNorm_smul_measure_of_ne_zero_of_ne_top {p : ℝ≥0∞} (hp_ne_zero : p ≠ 0)
769-
(hp_ne_top : p ≠ ∞) {f : α → F} (c : ℝ≥0∞) :
777+
(hp_ne_top : p ≠ ∞) {f : α → ε} (c : ℝ≥0∞) :
770778
eLpNorm f p (c • μ) = c ^ (1 / p).toReal • eLpNorm f p μ := by
771779
simp_rw [eLpNorm_eq_eLpNorm' hp_ne_zero hp_ne_top]
772780
rw [eLpNorm'_smul_measure ENNReal.toReal_nonneg]
@@ -872,7 +880,7 @@ theorem eLpNorm'_eq_zero_iff (hq0_lt : 0 < q) {f : α → E} (hf : AEStronglyMea
872880
eLpNorm' f q μ = 0 ↔ f =ᵐ[μ] 0 :=
873881
⟨ae_eq_zero_of_eLpNorm'_eq_zero (le_of_lt hq0_lt) hf, eLpNorm'_eq_zero_of_ae_zero hq0_lt⟩
874882

875-
theorem coe_nnnorm_ae_le_eLpNormEssSup {_ : MeasurableSpace α} (f : α → F) (μ : Measure α) :
883+
theorem coe_nnnorm_ae_le_eLpNormEssSup {_ : MeasurableSpace α} (f : α → ε) (μ : Measure α) :
876884
∀ᵐ x ∂μ, ‖f x‖ₑ ≤ eLpNormEssSup f μ :=
877885
ENNReal.ae_le_essSup fun x => ‖f x‖ₑ
878886

@@ -891,7 +899,7 @@ theorem eLpNorm_eq_zero_of_ae_zero {f : α → E} (hf : f =ᵐ[μ] 0) : eLpNorm
891899
rw [← eLpNorm_zero (p := p) (μ := μ) (α := α) (F := E)]
892900
exact eLpNorm_congr_ae hf
893901

894-
theorem ae_le_eLpNormEssSup {f : α → F} : ∀ᵐ y ∂μ, ‖f y‖ₑ ≤ eLpNormEssSup f μ :=
902+
theorem ae_le_eLpNormEssSup {f : α → ε} : ∀ᵐ y ∂μ, ‖f y‖ₑ ≤ eLpNormEssSup f μ :=
895903
ae_le_essSup
896904

897905
lemma eLpNormEssSup_lt_top_iff_isBoundedUnder :
@@ -900,7 +908,7 @@ lemma eLpNormEssSup_lt_top_iff_isBoundedUnder :
900908
simp_rw [← ENNReal.coe_le_coe, ENNReal.coe_toNNReal h.ne]; exact ae_le_eLpNormEssSup⟩
901909
mpr := by rintro ⟨C, hC⟩; exact eLpNormEssSup_lt_top_of_ae_nnnorm_bound (C := C) hC
902910

903-
theorem meas_eLpNormEssSup_lt {f : α → F} : μ { y | eLpNormEssSup f μ < ‖f y‖ₑ } = 0 :=
911+
theorem meas_eLpNormEssSup_lt {f : α → ε} : μ { y | eLpNormEssSup f μ < ‖f y‖ₑ } = 0 :=
904912
meas_essSup_lt
905913

906914
lemma eLpNorm_lt_top_of_finite [Finite α] [IsFiniteMeasure μ] : eLpNorm f p μ < ∞ := by
@@ -1097,7 +1105,6 @@ end BoundedSMul
10971105
The inequalities in the previous section are now tight.
10981106
-/
10991107

1100-
11011108
section NormedSpace
11021109

11031110
variable {𝕜 : Type*} [NormedDivisionRing 𝕜] [MulActionWithZero 𝕜 E] [Module 𝕜 F]

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