Workshop on Computability Theory and Foundations of Mathematics, Singapore

Workshop on Computability Theory and Foundations of Mathematics
(National University of Singapore, 8 – 12 September 2017)
Abstracts of talks should be submitted via email to
with subject line: CTFM2017 submission.
The length of abstract is limited to 2 pages including references.
The authors are recommended to prepare their abstracts in the
following IMS format:
IMPORTANT DATE. Submission deadline: September 1, 2017.
This workshop is the seventh in the Computability Theory and
Foundations of Mathematics (CTFM) series. CTFM aims to provide a forum
for computability theory and logical foundations of mathematics. The
topics include, but are not limited to, Computability / Recursion
Theory, Reverse Mathematics, Nonstandard Analysis, Proof Theory, Set
Theory, Philosophy of Mathematics, Constructive Mathematics,
Algorithmic Randomness and Computational Complexity.
CTFM began as a “Workshop on Proof Theory and Computability Theory”
and held its first meeting in Japan. Previous venues were Matsushima
(2008, 2009), Inawashiro (2010), Sendai (2011), Tokyo (2012). The
series assumed the name “Computability and Foundations of Mathematics”
at the 2013 meeting which was hosted in Tokyo. CTFM 2017 will be the
first time a meeting in the series is held outside Japan.
The previous meetings attracted not only researchers in Japan but also
many from around the world. In particular, since 2013, logicians from
Singapore have had frequent scientific exchanges with their Japanese
counterpart through the platform of the CTFM meetings.
The first day and the last day of the 2017 workshop will focus on
classical recursion theory, and computable structures as well as
reverse mathematics. The activities are held jointly with the program
Aspect of Computation. The other two days will focus on topics in set
theory and the foundations of mathematics.
Invited Speakers
Joerg Brendle (Kobe University, Japan)
Satoru Kuroda (Gunma Prefectural Women”s University, Japan)
Ludovic Patey (The University of California, Berkeley, USA)
Toshimichi Usuba (Waseda University, Japan)
Thomas Zeugmann (Hokkaido University, Japan)
Hao Zhaokuan (Fudan University, China)
Program Committee:
Dilip Raghavan (National University of Singapore)
Stephen Simpson (Pennsylvania State University)
Frank Stephan (National University of Singapore)
Kazuyuki Tanaka (Tohoku University) (Chair)
Yue Yang (National University of Singapore)
Keita Yokoyama (Japan Advanced Institute of Science and Technology)
Organizing Committee:
Chi Tat Chong (National University of Singapore)
Kazuyuki Tanaka (Tohoku University)
Guohua Wu (Nanyang Technological University)
Yue Yang (National University of Singapore)
Keita Yokoyama (Japan Advanced Institute of Science and Technology)

Third Hausdorff Medal 2017

Ladies and gentlemen, dear friends and colleagues!

It is my honor and pleasure to announce the winner of the third Hausdorff medal of the European Set Theory Society. The Hausdorff medal is awarded biennially (i.e. once every second year) for the most influential work in set theory published in the five years preceding the awarding of the medal. The prize committee, that consists of the members of the Board of Trustees of the Society, decided that the third Hausdorff medal is awarded to Maryanthe Malliaris and Saharon Shelah for their work outlined in the paper:

General topology meets model theory, on p and t. Proc. Natl. Acad. Sci. USA 110 (2013), no. 33, 13300-13305,

and then expounded in the detailed, 60 page long version:

Cofinality spectrum theorems in model theory, set theory, and general topology. J. Amer. Math. Soc. 29 (2016), no. 1, 237-297.


Malliaris and Shelah solved two long-standing and fundamental problems:

First, they solved a more than 50 year old set theoretic problem, going back to Rothberger, by showing that the well-known and important cardinal characteristics p and t of the continuum are actually equal.

Secondly, they solved a 40 year old problem in model theory by showing that the maximality in Keislers order is not characterized by the strict order property, but that a weak order property called SOP2 suffices.

Both results follow from a brilliant analysis of definability in ultraproducts of finite linear orders. This analysis is also unique in proving that there are theories more complex than the stable, i.e. minimal theories but less complex than the maximal class in Keisler’s order.

To conclude, this important work of Malliaris and Shelah opens the door for significant and fruitful new interactions between set theory and model theory.


Saharon Shelah, Maryanthe Malliaris, István Juhász, Jouko Väänänen – photo by Joan Bagaria


István Juhász, Saharon Shelah, Maryanthe Malliaris, Jouko Väänänen – photo by Joan Bagaria

Upcoming set theory meetings

May 29: Borel Reducibility of Equivalence Relations, Lausanne
June 20-25: Set Theoretic Pluralism – Symposium 2
June 26-30: Seventeenth Latin American Symposium on Mathematical Logic, Puebla, Mexico
June 27-30: 32nd Summer Conference on Topology and its Applications, Dayton, US
July 3-7: 6th European Set Theory Conference, Budapest
July 10-14: 10th Young Set Theory Workshop, Edinburgh
July 10-14: The 15th Asian Logic Conference, Korea
July 14-25: Graduate summer school: Classification problems in ergodic theory, Irvine
July 31-August 4: Applications of model theory to operator algebras, Houston
August 2-4: A conference on the occasion of Jensen’s 80th birthday, Münster
August 7-11: Nordic Logic Summer School 2017, Stockholm
August 14-18: Boolean Algebras, Lattices, Universal Algebra, Set Theory, Topology (BLAST), Nashville
August 14-20: Logic Colloquium 2017, Stockholm
August 20-September 1: Frontiers of Selection Principles, Warsaw
September 3-9: Set Theoretic Methods in Topology and Analysis, Bedlewo, Poland
September 6-8: Descriptive set theory in Torino
September 7-12: Set theoretic & Topological methods in Model Theory, Tezpur, India
September 10-12: Homogeneous structures, permutation groups, and connections to set theory, in honour of the 70th birthday of John Truss, Leeds
September 15-17: Simon Thomas: the first 60 years, Rutgers
October 9-13: The 14th international Luminy workshop on set theory, CIRM, Marseille
November 6-9: RIMS set theory meeting, Kyoto
November 13-17: Second Pan Pacific International Conference on Topology and its Applications, Busan, South Korea

Münster Set Theory Conference

A conference on the occasion of Ronald B. Jensen’s 80th birthday will take place from Aug 02–Aug 04, 2017 at the Institut für Mathematische Logik und Grundlagenforschung, WWU Münster.

List of speakers:
Gunter Fuchs (CUNY)
Moti Gitik (Tel Aviv University)
Menachem Magidor (Jerusalem)
Adrian Mathias (Reunion)
Bill Mitchell (U. Florida)
Itay Neeman (UCLA)
Grigor Sargsyan (Rutgers)
John Steel (Berkeley)
W. Hugh Woodin (Harvard)
Martin Zeman (UC Irvine)

Organizers: Menachem Magidor (Jerusalem), Ralf Schindler (Münster), John Steel (Berkeley), W. Hugh Woodin (Harvard)

In order to register for this conference, please send an email to Ralf Schindler at There is no registration fee, but we will ask participants for a small donation in order to cover expenses for coffee and cookies.

We can offer a few grants to doctoral students or post-doctoral researchers who are interested in attending this meeting and who do not have access to funding from a third source. If this applies to you, then please contact Ralf Schindler at

Extended deadline for the Young Set Theory Workshop 2017

Due to the availability of further places, the deadline for registering to the “New Directions in the higher infinite” (Young Set Theory) workshop has been extended to the 28th of April 2017. You can find the registration link at the following website:

which also contains information about the workshop, such as titles and abstracts for the invited talks. For any question, you may contact

With best regards,
The organisers

Bohuslav Balcar (1943-2017)

With deep sorrow we inform that Dr. Bohuslav Balcar passed away on Friday, February 17th, 2017.

Bohuslav Balcar was born in 1943. In 1965 he finished his studies at the Charles University in Prague under the supervision of P. Vopěnka. Although he obtained a degree in numerical mathematics, his main interests were mathematical logic, automata theory, and set theory. He was one of the original members of the Prague set theory seminar founded by P. Vopěnka in 1962. Between 1965 and 1975 he was a member of several departments at the Faculty of Mathematics and Physics of the Charles University, and in 1975 he started working at ČKD Semiconductors. While employed at the `factory’ as he liked to call the company, he was awarded the Candidate of Sciences (PhD) degree for his work on the theory of semisets, participated in a section of the `national fundamental research plan’ directed by Z. Frolík, and published his most important results. Together with P. Simon he lead the Seminar on Reckoning at Charles University, participated and later organized the Winter Schools in Abstract Analysis and Prague Topological Symposia. In 1989 he was awarded the Doctor of Science degree and started working in the Institute of Mathematics of the Czech Academy of Sciences. Since 1992 he was a member of the the Institute for Advanced Studies, joint research institute of the Charles University and the Czech Academy of Sciences.

Bohuslav Balcar’s mathematical interests included set theory, Boolean algebras, topological dynamics, and logic foundations. He officially supervised five graduate students, and many more had earned their degree under or benefited from his unofficial supervision. His influence shaped several generations of Czech set theoreticians.

Bohuslav Balcar was a kind, inspirational, and unresentful man. He will be greatly missed.