Examples:
\alpha ⟷ α
\mathcal{H} ⟷ ℋ
\beta ⟷ β
\gamma ⟷ γ
\sum ⟷ ∑
\int ⟷ ∫
Convert between LaTeX commands and Unicode characters
\alpha ⟷ α
\mathcal{H} ⟷ ℋ
\beta ⟷ β
\gamma ⟷ γ
\sum ⟷ ∑
\int ⟷ ∫