Under CH, $\cal P(\omega)/fin$ is atomless Boolean Algebra saturated and has cardinality $\aleph_1$. Why?
It has $2^{2^{\aleph_0}}$ automorphisms. Why exactly?
2026-03-29 03:36:01.1774755361
$\cal P(\omega)/fin$, automorphism, number of, $\aleph_1$,CH
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