scholarly journals WOODIN FOR STRONG COMPACTNESS CARDINALS

2019 ◽  
Vol 84 (1) ◽  
pp. 301-319
Author(s):  
STAMATIS DIMOPOULOS

AbstractWoodin and Vopěnka cardinals are established notions in the large cardinal hierarchy and it is known that Vopěnka cardinals are the Woodin analogue for supercompactness. Here we give the definition of Woodin for strong compactness cardinals, the Woodinised version of strong compactness, and we prove an analogue of Magidor’s identity crisis theorem for the first strongly compact cardinal.

2014 ◽  
Vol 79 (4) ◽  
pp. 1092-1119 ◽  
Author(s):  
WILL BONEY

AbstractWe show that Shelah’s Eventual Categoricity Conjecture for successors follows from the existence of class many strongly compact cardinals. This is the first time the consistency of this conjecture has been proven. We do so by showing that every AEC withLS(K) below a strongly compact cardinalκis <κ-tame and applying the categoricity transfer of Grossberg and VanDieren [11]. These techniques also apply to measurable and weakly compact cardinals and we prove similar tameness results under those hypotheses. We isolate a dual property to tameness, calledtype shortness, and show that it follows similarly from large cardinals.


1979 ◽  
Vol 44 (4) ◽  
pp. 563-565
Author(s):  
Carl F. Morgenstern

It is well known that the first strongly inaccessible cardinal is strictly less than the first weakly compact cardinal which in turn is strictly less than the first Ramsey cardinal, etc. However, once one passes the first measurable cardinal the inequalities are no longer strict. Magidor [3] has shown that the first strongly compact cardinal may be equal to the first measurable cardinal or equal to the first super-compact cardinal (the first supercompact cardinal is strictly larger than the first measurable cardinal). In this note we will indicate how Magidor's methods can be used to show that it is undecidable whether one cardinal (the first strongly compact) is greater than or less than another large cardinal (the first huge cardinal). We assume that the reader is familiar with the ultrapower construction of Scott, as presented in Drake [1] or Kanamori, Reinhardt and Solovay [2].Definition. A cardinal κ is huge (or 1-huge) if there is an elementary embedding j of the universe V into a transitive class M such that M contains the ordinals, is closed under j(κ) sequences, j(κ) > κ and j ↾ Rκ = id. Let κ denote the first huge cardinal, and let λ = j(κ).One can see from easy reflection arguments that κ and λ are inaccessible in V and, in fact, that κ is measurable in V.


1998 ◽  
Vol 63 (4) ◽  
pp. 1404-1412 ◽  
Author(s):  
Arthur W. Apter ◽  
Moti Gitik

AbstractWe show the consistency, relative to a supercompact cardinal, of the least measurable cardinal being both strongly compact and fully Laver indestructible. We also show the consistency, relative to a supercompact cardinal, of the least strongly compact cardinal being somewhat supercompact yet not completely supercompact and having both its strong compactness and degree of supercompactness fully Laver indestructible.


2000 ◽  
Vol 6 (1) ◽  
pp. 86-89
Author(s):  
James W. Cummings

1992 ◽  
Vol 57 (3) ◽  
pp. 970-974 ◽  
Author(s):  
Yo Matsubara

The large cardinal-like properties of saturated ideals have been investigated by various authors, including Foreman [F], and Jech and Prikry [JP], among others. One of the most interesting consequences of a strongly compact cardinal is the following theorem of Solovay [So2]: if a strongly compact cardinal exists then the singular cardinal hypothesis holds above it. In this paper we discuss the question of relating the existence of saturated ideals and the singular cardinal hypothesis. We will show that the existence of “strongly” saturated ideals implies the singular cardinal hypothesis. As a biproduct we will present a proof of the above mentioned theorem of Solovay using generic ultrapowers. See Jech and Prikry [JP] for a nice exposition of generic ultrapowers. We owe a lot to the work of Foreman [F]. We would like to express our gratitude to Noa Goldring for many helpful comments and discussions.Throughout this paper we assume that κ is a strongly inaccessible cardinal and λ is a cardinal >κ. By an ideal on κλ we mean a κ-complete fine ideal on Pκλ. For I an ideal on κλ let PI denote the poset of I-positive subsets of κλ.Definition. Let I be an ideal on κλ. We say that I is a bounding ideal if 1 ⊩-PI “δ(δ is regular cardinal ”.We can show that if a normal ideal is “strongly” saturated then it is bounding.Theorem 1. If 1 is an η-saturated normal ideal onκλ, where η is a cardinal <λsuch that there are fewer thanκmany cardinals betweenκand η (i.e. η < κ+κ), then I is bounding.Proof. Let I be such an ideal on κλ. By the work of Foreman [F] and others, we know that every λ+-saturated normal ideal is precipitous. Suppose G is a generic filter for our PI. Let j: V → M be the corresponding generic elementary embedding. By a theorem of Foreman [F, Lemma 10], we know that Mλ ⊂ M in V[G]. By η-saturation, cofinalities ≥η are preserved; that is, if cfvα ≥ η, then cfvα = cfv[G]α. From j ↾ Vκ being the identity on Vκ and M being λ-closed in V[G], we conclude that cofinalities <κ are preserved. Therefore if cfvα ≠ cfv[G]α then κ ≤ cfvα < η.


2011 ◽  
Vol 76 (4) ◽  
pp. 1441-1452 ◽  
Author(s):  
Remi Strullu

AbstractWe show that MRP + MA implies that ITP(λ,ω2) holds for all cardinal λ ≥ ω2. This generalizes a result by Weiβ who showed that PFA implies that ITP(λ, ω2) holds for all cardinal λ ≥ ω2. Consequently any of the known methods to prove MRP + MA consistent relative to some large cardinal hypothesis requires the existence of a strongly compact cardinal. Moreover if one wants to force MRP + MA with a proper forcing, it requires at least a supercompact cardinal. We also study the relationship between MRP and some weak versions of square. We show that MRP implies the failure of □(λ, ω) for all λ ≥ ω2 and we give a direct proof that MRP + MA implies the failure of □(λ, ω1) for all λ ≥ ω2.


2005 ◽  
Vol 70 (3) ◽  
pp. 767-777 ◽  
Author(s):  
John Krueger

AbstractWe construct a model in which there is a strongly compact cardinal κ such thai the set S(κ, κ+) ={ a Є Pκκ+: o.t.(a) = (a⋂ κ)+}is non-stationary.


Thomas Szasz ◽  
2019 ◽  
pp. 256-271
Author(s):  
Thomas Schramme

Szasz’s legacy involves two issues in current psychiatry: First, he criticized the concept of mental illness. The DSM-5 debate shows that psychiatry still suffers from unresolved conceptual problems. The definition of the general concept of mental disorder remains unclear. Specific classificatory entities (e.g., autism spectrum disorder) are notoriously contested. Second, he criticized coercive psychiatric practice. Recent developments suggest an ongoing identity crisis of psychiatry as a medical institution. Psychiatry’s tasks are partly related to societal interests (e.g., dealing with dangerous persons). Two psychiatric forms of intervention are therapeutic coercion and compulsion to prevent harm to others. Whether the latter can be squared with therapeutic purposes is unclear. To justify paternalistic interventions such as therapeutic coercion is difficult. Hence, there is enormous pressure on psychiatry’s medical identity. Szasz asked the right questions, not necessarily providing the most convincing answers. Psychiatry would benefit from a thorough, less prejudiced assessment of his publications.


Sign in / Sign up

Export Citation Format

Share Document