UNIVERSAL MAPPING PROPERTIES OF SOME PSEUDOVALUATION DOMAINS AND RELATED QUASILOCAL DOMAINS

If (R,M) and (S,N) are quasilocal (commutative integral) domains and f: R → S is a (unital) ring homomorphism, then f is said to be a strong local homomorphism (resp., radical local homomorphism) if f (M) = N (resp., f (M) ⊆ N and for each x ∈ N, there exists a positive integer t such that xt ∈ f (M)). It is known that if f: R → S is a strong local homomorphism where R is a pseudovaluation domain that is not a field and S is a valuation domain that is not a field, then f factors via a unique strong local homo-morphism through the inclusion map iR from R to its canonically associated valuation overring (M:M). Analogues of this result are obtained which delete the conditions that R and S are not fields, thus obtaining new characterizations of when iR is integral or radi-cial. Further analogues are obtained in which the “pseudovaluation domain that is not a field ” condition is replaced by the APVDs of Badawi-Houston and the “strong local homomorphism ” conditions are replaced by “radical local homomorphism.” Copyright © 2006 Hindawi Publishing Corporation. All rights reserved. 1