Thursday, October 11, 2018
3:00 PM - 4:00 PM
Linde Hall 255
Series: Logic Seminar Series
Marked groups with isomorphic Cayley graphs but different Borel combinatorics
Felix Weilacher, Department of Mathematics, Caltech,
We construct pairs of marked groups with isomorphic Cayley graphs but different Borel chromatic numbers for the free parts of their shift graphs. This answers a question of Kechris and Marks. We also show that these graphs have different Baire measurable and measure chromatic numbers, answering analogous versions of the question.