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P-ideal dichotomy and weak squares

Published online by Cambridge University Press:  12 March 2014

Dilip Raghavan
Dilip Raghavan*
Affiliation:
Department of Mathematics, University of Toronto, Toronto, ON M5S 2E4, Canada, E-mail: raghavan@math.toronto.edu, URL: http://www.math.toronto.edu/raghavan
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Abstract

We answer a question of Cummings and Magidor by proving that the P-ideal dichotomy of Todorčević refutes □κ,ω for any uncountable κ. We also show that the P-ideal dichotomy implies the failure of □κ,<b provided that cf(κ) > ω1.

Keywords

P-ideal dichotomyweak square principleAronszajn tree

Information

Type
Research Article
Information
The Journal of Symbolic Logic , Volume 78 , Issue 1 , March 2013 , pp. 157 - 167
Copyright
Copyright © Association for Symbolic Logic 2013

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References

REFERENCES

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