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arXiv · 2206.02228

On automorphisms of $\mathcal P(λ)/[λ]^{<λ}$

Jakob Kellner·Anda Latif·Saharon Shelah
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Abstract

We investigate the statement ``all automorphisms of $\mathcal P(λ)/[λ]^{<λ}$ are trivial''. We show that MA implies the statement for regular uncountable $λ<2^{\aleph_0}$; that the statement is false for measurable $λ$ if $2^λ=λ^+$; and that for ``densely trivial'' it can be forced (together with $2^λ=λ^{++}$) for inaccessible $λ$.

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Jakob Kellner, Anda Latif, Saharon Shelah. 2024-05-11. On automorphisms of $\mathcal P(λ)/[λ]^{<λ}$. https://arxiv.org/abs/2206.02228

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