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20092021
most citedMaximal almost disjoint families, determinacy, and forcing

6 citations · 6 across the 5 of their papers we have counts for

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math.LO2021

Set theory and a model of the mind in psychology

Asger Törnquist, Jens Mammen

We investigate the mathematics of a model of the human mind which has been proposed by the psychologist Jens Mammen. Mathematical realizations of this model consist of so-called \e…

math.LO2019

The Ramsey property implies no mad families

David Schrittesser, Asger Törnquist

We show that if all collections of infinite subsets of have the Ramsey property, then there are no infinite maximal almost disjoint (mad) families. This solves a long-standing…

math.LO2018★ 6 cited

Maximal almost disjoint families, determinacy, and forcing

Karen Bakke Haga, David Schrittesser, Asger Törnquist

We study the notion of -MAD families where is a Borel ideal on . We show that if is an arbitrary ideal, or is any finite or countably…

math.LO2011

Projective maximal families of orthogonal measures with large continuum

Vera Fischer, Sy-David Friedman, Asger Tornquist

We study maximal orthogonal families of Borel probability measures on (abbreviated m.o. families) and show that there are generic extensions of the constructible universe …

math.LO2009

A co-analytic maximal set of orthogonal measures

Vera Fischer, Asger Tornquist

We prove that if then there is a maximal orthogonal (i.e. mutually singular) set of measures on Cantor space. This provides a natural counterpoint to the well-known T…

math.LO2009

The Effective Theory of Borel Equivalence Relations

Ekaterina B. Fokina, Sy-David Friedman, Asger Tornquist

The study of Borel equivalence relations under Borel reducibility has developed into an important area of descriptive set theory. The dichotomies of Silver and Harrington-Kechris-L…