Cofinalities of Borel ideals

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985840%3A_____%2F14%3A00430394" target="_blank" >RIV/67985840:_____/14:00430394 - isvavai.cz</a>

Result on the web

<a href="http://dx.doi.org/10.1002/malq.201200079" target="_blank" >http://dx.doi.org/10.1002/malq.201200079</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1002/malq.201200079" target="_blank" >10.1002/malq.201200079</a>

Result language

angličtina

Original language name

Cofinalities of Borel ideals

Original language description

We study the possible values of the cofinality invariant for various Borel ideals on the natural numbers. We introduce the notions of a fragmented and gradually fragmented F sigma ideal and prove a dichotomy for fragmented ideals. We show that every gradually fragmented ideal has cofinality consistently strictly smaller than the cardinal invariant b and produce a model where there are uncountably many pairwise distinct cofinalities of gradually fragmented ideals.

Czech name

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Czech description

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Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

BA - General mathematics

OECD FORD branch

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Project

<a href="/en/project/IAA100190902" target="_blank" >IAA100190902: Mathematical logic, complexity, and algorithms</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)<br>I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2014

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Mathematical Logic Quarterly

ISSN

0942-5616

e-ISSN

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Volume of the periodical

60

Issue of the periodical within the volume

1-2

Country of publishing house

DE - GERMANY

Number of pages

9

Pages from-to

31-39

UT code for WoS article

000331901500005

EID of the result in the Scopus database

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