Crosscut
= Crosscut
A crosscut of a planar domain is a simple open arc inside the domain whose two endpoints are distinct boundary points, interpreted as <prime ends> when necessary. In a <simply connected domain> it divides the domain into two components. In the half-plane, a bounded crosscut joining two real points separates the intervening real interval from infinity; a <Loewner chain> completing that crosscut swallows this interval.