Joel David Hamkins conducts research in mathematical logic, particularly set theory, with a focus on the mathematics and philosophy of the infinite.
He has explored the interaction of forcing and large cardinals and recently initiated the research topics known as set-theoretic geology, which studies how the set-theoretic universe relates to all its various ground models, and the modal logic of forcing, which explores how it relates to all its various forcing extensions.
His philosophical work on the multiverse perspective participates in the emerging debate on pluralism in the philosophy of set theory.
In addition, Hamkins has undertaken work in infinitary computability, in group theory and on the hierarchy of equivalence relations on the natural numbers under computable reducibility.

His most recent theorem is that every countable model of set theory is isomorphic to a submodel of its own constructible universe.

Professor Hamkins earned his Ph.D at the University of California at Berkeley in 1994, and holds a permanent position as Professor at The City University of New York, at the Graduate Center of CUNY and at the College of Staten Island of CUNY.

Personal website


Recent and upcoming talks by Joel David Hamkins

Recent Developments in Axiomatic Set Theory, September 16-18, 2015

RIMS Set Theory Workshop 2015 Recent Developments in Axiomatic Set Theory   September 16 (Wed.) 14:20-14:50 Masaru Kada and Takuto Kato: Variants of AC under ZF minus union 15:10-15:40 Masaru Kada and Souji Shizuma: Some remarks on in nite hat guessing games 16:00-16:50 Makoto Takahashi: On non -shortness of Axiom A posets with frame systems September 17  (Thu.) 10:00-10:50 Teruyuki Yorioka: Some consistency results with the existence of a non special Aronszajn tree 11:10-12:00 David Chodounsky: F-Mathias reals and generic filters 14:00-14:50 Joel David Hamkins: Upward closure in the generic multiverse of a countable model of set theory 15:10-16:00 Toshimichi Usuba: Set-theoretic geology and large large cardinals 16:20-17:00 Tadatoshi Miyamoto: Side condition methods and morasses September 18 (Fri.) 9:00-9:50 Sakae Fuchino: On the superuniverse of the set theoretic multiverses 10:10-11:00 Hiroshi Sakai: Covering and approximation properties of ultrapower Venue Room 420, RIMS Kyoto Organizer Masahiro Shioya (University of Tsukuba), E-mail: shioya _at_ math.tsukuba.ac.jp continue reading…

Arthur Apter & Moti Gitik’s 60th birthday meeting, CMU, May 30-31 2015

There will be a meeting at CMU May 30-31 2015 in honour of Arthur Apter and Moti  Gitik. Speakers: Omer Ben-Neria Joel Hamkins Peter Koepke Menachem Magidor (canceled) Bill Mitchell Assaf Rinot Ralf-Dieter Schindler Dima Sinapova Hugh Woodin Timetable Saturday 30 May 8:45-9:30: Refreshments (Wean Hall 6220) 9:30-10:15: Assaf Rinot, “Putting a diamond inside the square”. continue reading…

BLAST 2015, 5-9 January 2015

BLAST is a conference focusing on Boolean Algebras Lattices, Algebraic and Quantum logic Universal Algebra Set Theory Set-theoretic and Point-free Topology BLAST circulates between different universities. Earlier BLAST meetings were held at the University of Denver (2008), New Mexico State University (2009), the University of Colorado at Boulder (2010), the University of Kansas (2011), and Chapman University (2013). continue reading…

Joel David Hamkins: Transfinite game values in infinite chess and other infinite games

Friday, May 23, 2014, 17.00 Lipschitzsaal, Mathematical Institute, University of Bonn Speaker: Joel David Hamkins (CUNY) Title: Transfinite game values in infinite chess and other infinite games continue reading…

21/Apr/2014: Grigor Sargsyan and Joel Hamkins

All talks are in Hill DST Seminar at 3:20 Room 525 Monday 04/21 — Grigor Sargsyan (Rutgers) Title: Stability and Morley rank IX Logic Seminar at 5:00 Room 705 Monday 04/21 — Joel Hamkins (College of Staten Island) Title: Large cardinals need not be large in HOD Abstract: I will show that large cardinals, such as measurable, strong and supercompact cardinals, need not exhibit their large cardinal nature in HOD. continue reading…

21st Boise Extravaganza in Set Theory, June 18-20, 2014

BOISE EXTRAVAGANZA IN SET THEORY (BEST) June 18 – 20, 2014 University of California, Riverside The 21-st meeting of BEST will be hosted at University of California, Riverside, as a symposium of the 95th annual meeting of the American Association for the Advancement of Science – Pacific Division (AAAS-PD). continue reading…

Infinity, computability, and metamathematics, May 23 -25, 2014

“Infinity, computability, and metamathematics: Celebrating the 60th birthdays of Peter Koepke and Philip Welch” In the year 2014, Peter Koepke and Philip Welch are celebrating their 60th birthdays, and we wish to celebrate this festive occasion with a scientific workshop in their honor. continue reading…

2014 North American Annual ASL Meeting, May 19 – 22, 2014

2014 ASL North American Annual Meeting. May 19–22, 2014, Boulder, Colorado. The invited speakers are: L. Barto, B. Csima, V. de Paiva, J. Hirst, M. Hrusak, A. Kolesnikov, A. Marks, M.C. continue reading…

This Week in Logic at CUNY

Set theory seminar Friday, September 27, 2013 10:00 am 6417 Speaker: Gunter Fuchs The City University of New York Title: A self-specializing Souslin tree Link: http://nylogic.org/talks/a-self-specializing-souslin-tree  I will present a construction, assuming Jensen’s combinatorial principle diamond, of a Souslin tree T which, after forcing with T, will be Ahronszajn off the generic branch. continue reading…

This Week in Logic at CUNY

This Week In Logic at CUNY Computer Science Colloquium and Computational Logic Seminar Thursday September 19, at 4:15, Room 3209 (NOTE: there will be no Seminar Meeting on Tuesday September 17) Speaker: Rohit Parikh, Brooklyn College and the Graduate Center. continue reading…