Variation formulas for principal functions (II) Applications to variation for harmonic spans

S. Hamano, F. Maitani, H. Yamaguchi

For a domain $D$ in ${\mathbb{C}}_z$ with smooth boundary and for $a,b\in D,a\ne b$, we have the circular (radial) slit mapping $P(z)(Q(z))$ on $D$ such that $P(z)- \frac{1}{z-a}\ (…