Topic
Morass
About: Morass is a research topic. Over the lifetime, 35 publications have been published within this topic receiving 160 citations.
Papers
TL;DR: A new partial order for directly forcing morasses to exist that enjoys a significant homogeneity property is presented, and universal morasses are consistent with n-superstrong, hyperstrong, and 1-extendible cardinals.
18 citations
TL;DR: The converse of Jensen's result is proved, i.e., that if there is a ( k , 2)-simplified morass then there isA ( k, 2)-morass.
Abstract: This paper concerns the theory of morasses. In the early 1970s Jensen defined (k, α)-morasses for uncountable regular cardinals k and ordinals α k . In the early 1980s Velleman defined ( k , 1)-simplified morasses for all regular cardinals k . He showed that there is a ( k , 1)-simplified morass if and only if there is ( k , 1)-morass. More recently he defined ( k , 2)-simplified morasses and Jensen was able to show that if there is a ( k , 2)-morass then there is a ( k , 2)-simplified morass. In this paper we prove the converse of Jensen's result, i.e., that if there is a ( k , 2)-simplified morass then there is a ( k , 2)-morass.
14 citations
TL;DR: Using “generic modification”, it is shown that over the ground model L, models witnessing Easton’s theorem can be obtained as inner models of L, for Easton functions which are L-definable with parameters at most ω1L[0#].
8 citations
TL;DR: In this article, the existence of a gap 2 Morass and the principle Diamond (♢) imply 1) ω α+2 ≠ [ω α+1 + ωα ⤳ α + 1, 2] a combinatorial principle which extends a principle of Prikry, 3) a result concerning free sets of ordinals related to problems posed by Hajnal and Mate.
7 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2020 | 1 |
| 2015 | 1 |
| 2014 | 2 |
| 2012 | 1 |
| 2011 | 4 |
| 2010 | 3 |