Weakly Ramsey 𝑃 points

Rosen, Ned I.

doi:10.1090/S0002-9947-1982-0637699-4

Weakly Ramsey $P$ points
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Trans. Amer. Math. Soc. 269 (1982), 415-427 Request permission

Abstract:

If the continuum hypothesis (CH) holds, then for any $n$ Ramsey $P$ point $D$ and any $k \geqslant 1$ there exist many $n + k$ Ramsey $P$ points which are immediate Rudin-Keisler successors of $D$. There exist (CH) many 5 Ramsey $P$ points whose constellations are not linearly ordered.

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