Document Type

Article

Language

eng

Publication Date

1-1993

Publisher

American Mathematical Society

Source Publication

Transactions of the American Mathematical Society

Source ISSN

0002-9947

Original Item ID

DOI: 10.1090/S0002-9947-1993-1155348-3

Abstract

A subset P of an abstract algebra A is a pseudobasis if every function from P into A extends uniquely to an endomorphism on A. A is called K-free has a pseudobasis of cardinality K; A is minimally free if A has a pseudobasis. (The 0-free algebras are "rigid" in the strong sense; the 1-free groups are always abelian, and are precisely the additive groups of E-rings.) Our interest here is in the existence of pseudobases in direct powers AI of an algebra A. On the positive side, if A is a rigid division ring, K is a cardinal, and there is no measurable cardinal u with , then AI is K-free whenever . On the negative side, if A is a rigid division ring and there is a measurable cardinal u with ,then AI is not minimally free.

Comments

Published version. Transactions of the American Mathematical Society, Vol. 335, No. 1 (January 1993): 79-90. DOI. © 1993 The American Mathematical Society Used with permission.

Share

COinS