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Photo of Jonas Reitz with multiple reflections

My name is Jonas Reitz, and I am a Professor in the Mathematics Department at City Tech. My research interests are in mathematical logic, especially set theory. I enjoy pondering questions like “do sets really exist?” and “what does it mean to be a real number?” and “if sets do exist, is there a universe of sets?” I have an unhealthy fascination with the method...

My Mathematical Geneology

Tree growing out of ruins. Photo from:

Courtesy of the most excellent Mathematics Geneology Project. Me: Jonas Reitz My mathematical parent (graduate advisor): Joel David Hamkins My mathematical grandparent: William Woodin My mathematical great-grandparent: Robert Solovay My mathematical great-great-grandparent: Saunders Mac Lane My mathematical great-great-great-grandparent: Hermann Weyl My mathematical great-great-great-great...

Inner-Model Reflection Principles

A lit up object sitting on top of a table

This paper has its origins in a question by Neil Barton on Math.SE, “What is the consistency strength of width-reflection?” Start with one of the foundational relationships of set theory, that of height-reflection — any property true in the universe $V$ is true in some initial segment $V_\kappa$. Then “rotate your head ninety degrees” and consider the corresponding...

Metro NExt 9/19: Subversive Compromise

subversive monkeys

Subversive Compromise:Working in and around the system to write a grant, get funded, and make stuff happen. Metro NExT (New Experiences in Teaching) Workshop 2019September 13, 2019 – Courant/NYU (251 Mercer St.), Room 109 ABSTRACT:In this interactive workshop, participants will explore challenges, opportunities and lessons learned in conceiving, planning, designing, and writing a successful...

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