My name is Florian Sprung. Some people call me Ian Sprung. My work is in arithmetic geometry and number theory and currently supported by NSF grant 2001280. My Erdős number is three.

You can reach me here.

Here is my teaching page.


  • Chromatic Selmer groups for imaginary quadratic fields

to appear in J.T. Nombres de Bordeaux

with Cédric Dion, published in Abhandlungen aus dem mathematischen Seminar Hamburg

with Antonio Lei, published in Israel Journal of Mathematics

(Video available here.)

with F. Castella, M. Ciperiani, and C. Skinner


published in RIMS Bessatsu

with Ken Ono and Larry Rolen, published in Advances in Mathematics

published in Research in Number Theory

published in Algebra and Number Theory

published in Journal für die reine und angewandte Mathematik (Crelles Journal)

published in RIMS Bessatsu

published in the Journal of Number Theory

(The video features Shinichi Kobayashi and Robert Pollack)

published in the Proceedings of the 6th Kinosaki Shinjin Seminar

Before getting into academia, I worked at the Kirakuen retirement home.

Here is an essay by Kodaira on how to read.