Past exam of the mathematics course of the University of Cambridge 2024 iii Paper 203 1 a Solution Created 2026-09-24 Updated 2026-09-25
A compact H-hull is a bounded relatively closed set for which is a simply connected domain. The Riemann mapping theorem and hydrodynamic normalization at infinity give a unique mapping-out function of a compact H-hull withThe coefficient is the half-plane capacity .
For and , uniqueness of the normalized map givesSubstituting the expansion of yieldsTherefore the scaling and translation of half-plane capacity is
Past exam of the mathematics course of the University of Cambridge 2024 iii Paper 203 1 b ii Solution Created 2026-09-24 Updated 2026-09-25
For , let . The Brownian representation of half-plane capacity givesOn hitting the imaginary part is at most one, while the harmonic measure estimate supplied in the question shows that the probability of reaching a disc of radius containing is . Hence , the half-plane capacity of a low rectangle bound.
SetThe scaling and translation of half-plane capacity giveswhereas . This supplies the required sequence.
Past exam of the mathematics course of the University of Cambridge 2024 iii Paper 203 1 c Solution Created 2026-09-24 Updated 2026-09-25
Let . Since , the scaling and translation of half-plane capacity givesThe half-plane-capacity parameterization requires , so