NAMBA FORCING, WEAK APPROXIMATION, AND GUESSING
نویسندگان
چکیده
منابع مشابه
Kurepa trees and Namba forcing
We show that compact cardinals and MM are sensitive to λ-closed forcings for arbitrarily large λ. This is done by adding ‘regressive’ λ-Kurepa-trees in either case. We argue that the destruction of regressive Kurepa-trees with MM requires the use of Namba forcing.
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Forcing is a technique that was discovered by Cohen in the mid 20th century, and it is particularly useful in proving independence results. The process involves adding new, generic elements to your universe and using them to prove a result. In many applications this is encapsulated by the addition of suitable axioms, often these are Forcing Axioms. One of the first such principles is known as M...
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ژورنال
عنوان ژورنال: The Journal of Symbolic Logic
سال: 2018
ISSN: 0022-4812,1943-5886
DOI: 10.1017/jsl.2018.30