Collapsing algebra
In mathematics, a collapsing algebra is a type of Boolean algebra sometimes used in forcing to reduce ("collapse") the size of cardinals. The posets used to generate collapsing algebras, were introduced by Azriel Lévy (1963).
Definition
If κ and λ are cardinals, then the Boolean algebra of regular open sets of the product space κλ is called a collapsing algebra.
References
- Bell, J. L. (1985) Boolean-Valued Models and Independence Proofs in Set Theory, Oxford. ISBN 0-19-853241-5
- Jech, Thomas (2002). Set theory, third millennium edition (revised and expanded). Springer. ISBN 3-540-44085-2. OCLC 174929965.
- Lévy (1963), "Independence results in set theory by Cohen's method. IV", Notices Amer. Math. Soc., 10: 593
{{citation}}: line feed character in|journal=at position 15 (help)