Abstract
A result of Zelevinsky states that an orbit closure in the space of representations of the equioriented quiver of type
A
h
is in bijection with the opposite cell in a Schubert variety of a partial flag variety
SL(n)/Q
. We prove that Zelevinsky's bijection is a scheme-theoretic isomorphism, which shows that the universal degeneracy schemes of Fulton are reduced and Cohen-Macaulay in arbitrary characteristic.