Hilbert Space

★★★★☆Undergraduate

📖Definition

Complete space with inner product. Infinite-dimensional generalization of Euclidean space

📐Formulas

⟨x, y⟩ = ⟨y, x⟩̄ (conjugate symmetry)
⟨x, x⟩ ≥ 0
||x|| = √⟨x, x⟩
Orthonormal basis: ⟨eᵢ, eⱼ⟩ = δᵢⱼ

✏️Examples

예제 1

L²(ℝ)

예제 2

ℓ²

예제 3

Quantum state space

Applications

Quantum mechanics

Fourier analysis

Signal processing

#힐베르트#Hilbert#내적#inner-product