3 papers
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…