Cauchy Integral Theorem & Residue Calculus

Complex Analysis Source: Cauchy (1825) Cite
Primary: Augustin-Louis Cauchy
Publication: Residue theorem
Year: 1825
URL: Wikipedia

∫_γ f(z) dz = 0 for null-homologous γ. Cauchy integral formula, residue theorem. Main computational tool for contour integrals.

graph TD D1["Def: Contour integral\n∫_γ f dz"] D2["Def: Winding number\nn(γ,z)"] D3["Def: Residue\nRes(f,z₀)"] T1["Thm: Cauchy–Goursat\n∫_γ f=0 if f holomorphic\ninside γ"] T2["Thm: Cauchy formula\nf(z)=1/2πi ∫ f(ζ)/(ζ−z) dζ"] T3["Thm: Residue theorem\n∫_γ f = 2πi Σ Res(f,zⱼ)"] T4["Thm: Argument principle\n∫ f'/f = 2πi(N−P)"] T5["Thm: Rouché\n|f−g|<|g| ⇒ same # zeros"] L1["Lemma: Laurent coeff\nc₋₁ = Res"] T1 --> T2 T2 --> T3 T2 --> L1 L1 --> T3 T3 --> T4 T4 --> T5 D1 --> T1 D2 --> T4 D3 --> T3 classDef definition fill:#b197fc,color:#fff classDef theorem fill:#51cf66,color:#fff classDef lemma fill:#74c0fc,color:#fff class D1,D2,D3 definition class T1,T2,T3,T4,T5 theorem class L1 lemma

Process Statistics

  • Nodes: 15
  • Edges: 14
  • Definitions: 3
  • Theorems: 5
  • Lemmas: 1
Frontier: Tropical residues, higher residues, applications to mirror symmetry. math.CV