R. J. Koch proved that if X is a
compact, continuously partially ordered space and if W is an open subset of X which
has no local minima, then each point of W is the supremum of an order arc which
meets X −W. More recently he extended this result to quasi ordered spaces in which
the sets E(x) = {y : x ≦ y ≦ x} are assumed to be totally disconnected and W is a
chain. He conjectured that the latter hypothesis is superfluous, and we show here
that Koch’s conjecture is correct.
As a corollary it follows that if X is a compact, continuously quasi ordered
space with zero (i.e., a unique minimal element), if each set E(x) is totally
disconnected, and if each set L(x) = {y : y ≦ x} is connected, then X is arcwise
connected.
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