Sean Cox, Ph.D.

Associate Professor

Associate Chair / Director of Undergraduate Studies

Grace E. Harris Hall, 1015 Floyd Ave., room 4167


  • PhD in Mathematics, University of California Irvine, 2009 [Dissertation: “Covering theorems for the core model, with applications”; Adviser: Martin Zeman (Received the Mathematics Department’s Kovalevsky Outstanding PhD Thesis Award for 2008-09)]
  • BA in Economics, North Carolina State University, 1999

Research Interests

Cox's research area is Mathematical Logic and Set Theory, where he often try to determine whether certain mathematical problems can be solved within standard axiomatic systems. Gödel’s Incompleteness Theorems and subsequent research, including some of his own, have revealed many interesting problems for which there is no such solution.

Select Publications

  • Salce's problem on cotorsion pairs is undecidable. Bull. London Math. Soc..
  • Maximum Deconstructibility in module categories.  Journal of Pure and Applied Algebra 226 (2022), no. 5.
  • Forcing axioms, approachability, and stationary set reflection, J. Symbolic Logic 86 (2021), no. 2, 499–530.
  • (with Monroe Eskew) Strongly proper forcing and some problems of Foreman, Transactions of the American Mathematical Society 371 (2019), no. 7, 5039–5068.
  • Chang’s Conjecture and semiproperness of nonreasonable posets, Monatshefte für Mathematik 187 (2018), no. 4, 617-633.
  • (with John Krueger) Quotients of strongly proper forcings and guessing models, J. Symb. Log. 81 (2016), no. 1, 264-283.
  • Covering Theorems for the core model, with an application to stationary set reflection, Annals of Pure and Applied Logic 161 (2009), pp. 66-93.

Professional Appointments

  • Associate Professor,  Virginia Commonwealth University, Department of Mathematics and Applied Mathematics (July 2018 to present)   
  • Assistant Professor, Virginia Commonwealth University, Department of Mathematics and Applied Mathematics (Fall 2012 to June 2018; on leave during Fall 2012)
  • Fields Postdoctoral Fellow at the Thematic Program on Forcing and its Applications (Fields Institute, July-December 2012)
  • Akademischer Rat auf Zeit (postdoctoral position), Institute for Mathematical Logic and Basic Research, University of Münster, Germany (November 2009 to May 2012)


  • NSF grant DMS-2154141 (PI), 9/1/2022 - 8/31/2025 (estimated), $180,000. Project title: Approximation theory and elementary submodels.
  • VCU Seed Award (PI), 7/1/2021 - 5/31/2023 (est.), $5,000. Project title: How Robustly Can You Predict the Future?
  • VCU Presidential Research Quest Fund (PI), 7/1/16-12/31/17, $40,000. Project title: Open problems in the foundations of mathematics. Co-PIs: Brent Cody and Monroe Eskew.
  • Simons Foundation Collaboration Grant for Mathematicians (PI), 2014–2019, $35,000. Project title:  Forcing and the nonstationary ideal.