Joan Bagaria

Universitat de Barcelona

Experimental Sciences & Mathematics

Born on 17 August 1958 in Manlleu (Catalonia). Fulbright Fellow at Univ. of California, Berkeley, 1985-87. PhD in Logic and the Methodology of Science, UC Berkeley, 1991. Postdoctoral researcher, UC Berkeley, 1991-92. Associate Professor at several Catalonian universities, 1992-2001. ICREA Research Professor at Univ. of Barcelona, since 2001. Invited researcher at UC Berkeley, Kobe Univ., National Univ. of Singapore, Kurt Gödel Research Center (Vienna), Univ. Paris VII, CalTech, Mittag-Leffler Institut, Hebrew Univ., Harvard Univ., etc. First President of the European Set Theory Society, 2007-11; ICREA Director's Scientific Advisor, since 2005; Chairman of the INFTY ESF-Research Networking Programme, 2009-14; Simons Foundation Fellow at Isaac Newton Institute, Cambridge, UK, Aug. to Dec. 2015. Director of the Barcelona research group on set theory (BCNSETS) and PI of the UB-based Group in Logic.


Research interests

I am a mathematical logician working mainly in set theory, an extremely general mathematical theory whose objects of study are the abstract infinite sets. Set theory is the strongest and most encompassing theory ever developed. It is both the mathematical theory of infinity and the standard foundation for mathematics, in the sense that virtually all of mathematics can be formally reduced to it. I help to develop and apply sophisticated theories and techniques, such as forcing and large cardinals, towards the solution of hard problems in set theory itself and in other areas of logic and mathematics. More interestingly, it is sometimes possible to prove that a given problem cannot be solved using standard mathematical tools, which are embodied in the standard ZFC axioms of set theory, and therefore new axioms are needed for its solution. Finding and classifying new axioms, thereby expanding the frontiers of mathematical reasoning, is also an essential part of set theory, and of my work.


Selected research activities

Invited talks

  • The role of Large Cardinals in the semantics of Generalized Provability Logics. The First Mexico/USA Logic Fest, ITAM, Ciudad de México. 9 Jan, 2018
  • La Hipótesis del Continuo, 140 años después. Jornada principal del año Cantor. Instituto de Matemáticas de la Universidad de Sevilla (IMUS), 14 Feb. 2018
  • Some considerations around the Weak Vopěnka Principle. Accessible categories and their connections. School of Mathematics, University of Leeds (UK). 17-20 July 2018
  • Preserving the reflection properties of the set-theoretic universe under forcing. Cantor meets Robinson – Set Theory, Model Theory, and their Philosophy. University of Campinas (Brazil). 12-15 December 2018.

Advanced mini-course

  • Strong axioms of infinity as reflection principles. Mini-course consisting of 3 sessions of 90 minutes each. Cantor meets Robinson – Set Theory, Model Theory, and Their Philosophy. Instituto de Matemática e Estatística, Universidade de São Paulo (Brazil). 3-7 December 2018.

Invited participant

  • 1st Girona conference on inner model theory. Universitat de Girona (Catalonia). July 16-27, 2018.
  • Reflections on Set-Theoretic Reflection. Set Theory Conference, organised in partnership with the Clay Mathematics Institute, in celebration of Joan Bagaria’s 60th Birthday. Sant Bernat, Montseny (Catalonia). 16-19 November 2018.

Managerial activities

  • Member of the Program Committee. “Novi Sad Conference in Set theory and General Topology” (SETTOP 2018). July 2-5, 2018, Novi-Sad (Serbia).