Hannes Jakob

I am a postdoctoral researcher in set theory. This field is concerned with studying the properties of different infinities. At this moment, I am mostly interested in compactness principles, large cardinals and singular cardinal combinatorics. After receiving my PhD from the University of Freiburg under my advisor Heike Mildenberger, I am now a Visiting Assistant Professor at the University of North Texas, being mentored by John Krueger. For more information, you can look at my PhD Thesis or my CV (updated 30th of December 2025).

Papers and Preprints

• Disjoint Stationary Sequences on an Interval of Cardinals, Fundamenta Mathematicae, 269 (3): 261-283, 2025. [pdf/arxiv]

• Slender Trees and the Approximation Property, Archive for Mathematical Logic, accepted. [pdf/arxiv]

• (with Maxwell Levine) Distinguishing Internally Club and Approachable on an Infinite Interval, Bulletin of the London Mathematical Society, 57 (4): 1026-1039, 2024. [pdf/journal]

• Cascading Variants of Internal Approachability, submitted. [pdf/arxiv]

• On Friedman's Property, submitted. [pdf/arxiv]

• (with Maxwell Levine) Failure of Approachability at the Successor of the first Singular for any Cofinality, submitted (revised November 2025). [pdf/arxiv]

• Total Failure of Approachability at Successors of Singulars of Countable Cofinality, submitted (revised February 2026). [pdf/arxiv]

• (with Alejandro Poveda) On Shelah's Approachability Ideal, submitted. [pdf/arxiv]