Two ways to approximate a proximity relation R (i.e. a reflexive and symmetric fuzzy relation) by a T-transitive one where T is a continuous archimedean t-norm are given. The fi...
A subset U of a set S with a binary operation is called avoidable if S can be partitioned into two subsets A and B such that no element of U can be written as a product of two dis...
We prove that every homogeneously Souslin set is coanalytic provided that either (a) 0long does not exist, or else (b) V = K, where K is the core model below a