Joseph Albert Helfer

I am an assistant professor in mathematics at the University of Southern California. I study symplectic and algebraic geometry, and categorical logic.
I completed my PhD at Stanford University under the supervision of Yasha Eliashberg in Symplectic Geometry
Before that, I completed my Master's degree at McGill University under the supervision of Dani Wise in Geometric Group Theory


Fall 2022, Math 440 (Topology)

In previous semesters, I've taught Math 540 (Algebraic Topology) and Math 471 (Linear Algebra).

Things I've written


Homotopies in Grothendieck fibrations. 2019. (Preprint)

Counting cycles in labeled graphs: The nonpositive immersion property for one-relator groups (with Dani Wise). 2015. (Preprint)

A Note on Maxima in Random Walks (with Dani Wise). 2016.


Exotic tight contact structures on R4m+1 (with Fran├žois-Simon Fauteux-Chapleau). 2021.

First-order homotopical logic. 2019.


The ugly truth about simplicial sets.

The first talk of the Fall 2017 HTTCLHIE seminar.


My CEGEP independent study project. It describes the implementation of a Unix shell.

My Bachelor's thesis, about computing the space of Delaunay triangulations of a punctured Riemann surface. Here is the accompanying code.

My Master's thesis, which is an expanded version of the paper with Dani Wise (above) about counting cycles in labeled graphs.

My PhD thesis on contact homology for open manifolds.


After all, what's the point if you don't have a little fun?
To me, fun primarily means generating various lists.
Also this.

Contacting me

See here.