60 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Lean4
		
	
	
	
	
	
			
		
		
	
	
			60 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			Lean4
		
	
	
	
	
	
| import Mathlib.Data.Fin.Tuple.Basic
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| import Mathlib.Analysis.Complex.Basic
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| import Mathlib.Analysis.Complex.TaylorSeries
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| import Mathlib.Analysis.Calculus.LineDeriv.Basic
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| import Mathlib.Analysis.Calculus.ContDiff.Defs
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| import Mathlib.Analysis.Calculus.FDeriv.Basic
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| import Mathlib.Analysis.Calculus.FDeriv.Symmetric
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| import Mathlib.Data.Complex.Module
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| import Mathlib.Data.Complex.Order
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| import Mathlib.Data.Complex.Exponential
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| import Mathlib.Analysis.RCLike.Basic
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| import Mathlib.Topology.Algebra.InfiniteSum.Module
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| import Mathlib.Topology.Instances.RealVectorSpace
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| import Nevanlinna.cauchyRiemann
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| import Nevanlinna.partialDeriv
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| 
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| variable {F : Type*} [NormedAddCommGroup F] [NormedSpace ℝ F]
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| 
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| 
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| noncomputable def Complex.laplace : (ℂ → F) → (ℂ → F) :=
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|   fun f ↦ partialDeriv ℝ 1 (partialDeriv ℝ 1 f) + partialDeriv ℝ Complex.I (partialDeriv ℝ Complex.I f)
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| 
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| 
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| theorem laplace_add {f₁ f₂ : ℂ → F} (h₁ : ContDiff ℝ 2 f₁)  (h₂ : ContDiff ℝ 2 f₂): Complex.laplace (f₁ + f₂) = (Complex.laplace f₁) + (Complex.laplace f₂) := by
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|   unfold Complex.laplace
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|   rw [partialDeriv_add₂]
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|   rw [partialDeriv_add₂]
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|   rw [partialDeriv_add₂]
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|   rw [partialDeriv_add₂]
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|   exact
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|     add_add_add_comm (partialDeriv ℝ 1 (partialDeriv ℝ 1 f₁))
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|       (partialDeriv ℝ 1 (partialDeriv ℝ 1 f₂))
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|       (partialDeriv ℝ Complex.I (partialDeriv ℝ Complex.I f₁))
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|       (partialDeriv ℝ Complex.I (partialDeriv ℝ Complex.I f₂))
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| 
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|   exact (partialDeriv_contDiff ℝ h₁ Complex.I).differentiable le_rfl
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|   exact (partialDeriv_contDiff ℝ h₂ Complex.I).differentiable le_rfl
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|   exact h₁.differentiable one_le_two
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|   exact h₂.differentiable one_le_two
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|   exact (partialDeriv_contDiff ℝ h₁ 1).differentiable le_rfl
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|   exact (partialDeriv_contDiff ℝ h₂ 1).differentiable le_rfl
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|   exact h₁.differentiable one_le_two
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|   exact h₂.differentiable one_le_two
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| 
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| 
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| 
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| theorem laplace_smul {f : ℂ → F} (h : ContDiff ℝ 2 f) : ∀ v : ℝ, Complex.laplace (v • f) = v • (Complex.laplace f) := by
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|   intro v
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|   unfold Complex.laplace
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|   rw [partialDeriv_smul₂]
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|   rw [partialDeriv_smul₂]
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|   rw [partialDeriv_smul₂]
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|   rw [partialDeriv_smul₂]
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|   simp
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| 
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|   exact (partialDeriv_contDiff ℝ h Complex.I).differentiable le_rfl
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|   exact h.differentiable one_le_two
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|   exact (partialDeriv_contDiff ℝ h 1).differentiable le_rfl
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|   exact h.differentiable one_le_two
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