No events are planned

Krajíček Jan

Prof., RNDr., DrSc.
Born June 18, 1960 in Prague

  • Member of Learned Society since 2004

Educational and professional preparation

  • 1985, RNDr., Charles University;
  • 1990, CSc., Czechoslovak Academy of Sciences;
  • 1993, DrSc., AS CR;
  • 2002, Associate Professor, CU;
  • 2004, Professor of Mathematical Logic, CU;

Employment and academic positions

  • 1985-present, Academy of Sciences;
  • 2000-present, Charles University;
  • 1988-89, 1990-91, visiting professor, University of Illinois (Urbana-Champaign);
  • 1993, visiting professor (six months), University of Toronto;
  • 1997-99, visiting scholar, Oxford University;
  • 2004 (Spring term), member, Institute for Advanced Study, Princeton.
  • 2006 and 2012 (Spring terms), senior visiting fellow, Isaac Newton Institute, Cambridge.

Membership and positions in international organizations and societies

  • Association for Symbolic Logic Concilium (1999-2001 Council, 2002-2005 Committee on Logic in Europe, 2006-present Committe on Prizes and Awards)
  • Member, American Mathematical Society
  • 2009-present, Panel Member for the ERC Advanced Grant evaluation
  • Member, editorial boards, Annals of Pure and Applied Logic, Notre Dame Journal of Formal Logic, Archive for Mathematical Logic, and Mathematical Methods in Computer Science
  • over the years, member of program/organization committees of over 30 international conferences

Notable awards

  • 1994, Award, young scientific workers, AS CR
  • 1998, Award, Minister of Education, Youth and Sports (for Science)
  • 2010, Award of the Academy of Sciences of the Czech Republic

Selected publications

  • J. Krajíček: On the Number of Steps in Proofs. Annals of Pure and Applied Logic 41(2), 153-178, (1989)
  • J. Krajíček, P. Pudlák and G. Takeuti: Bounded Arithmetic and the Polyno-mial Hierarchy, Annals of Pure and Applied Logic 52, 143-153, (1991).
  • J. Krajíček: Fragments of Bounded Arithmetic and Bounded Query Classes, Transactions of the AMS 338(2), 587-598, (1993).
  • J. Krajíček: Lower Bounds to the Size of Constant-Depth Propositional Proofs. J. of Symbolic Logic 59(1), 73-86, (1994).
  • J. Krajíček, P. Pudlák and A. Woods: An Exponential Lower Bound to the Size of Bounded Depth Frege Proofs of the Pigeonhole principle. Random Structures and Algorithms 7(1), 15-39,(1995).
  • P. Beame, R. Impagliazzo, J. Krajíček, T. Pitassi and P. Pudlák: Lower bounds on Hilbert.s Nullstellensatz and propositional proofs. Proceedings of the London Mathematical Society 73(3), 1-26, (1996).
  • J. Krajíček: Interpolation theorems, lower bounds for proof systems, and independence results for bounded arithmetic. J. of Symbolic Logic, 62(2), 457-486, (1997).
  • J. Krajíček a P. Pudlák: Some consequences of cryptographical conjectures for S12 and EF. Information and Computation 140 (1), 82-94, (1998).
  • J. Krajíček: Dual weak pigeonhole principle, pseudo-surjective functions, and provability of circuit lower bounds, J. of Symbolic Logic, 69(1), 265-286, (2004).
  • J. Krajíček: An exponential lower bound for a constraint propagation proof system based on ordered binary decision diagrams, J. of Symbolic Logic, 73(1), 227-237, (2008).
  • J. Krajíček: Bounded arithmetic, propositional logic, and complexity theory, Cambridge University Press, 1995.
  • J. Krajíček: Forcing with random variables and proof complexity, Cambridge University Press, 2011.

reference to the website »

Back to the list of articles



Luboš Perek is celebrating his 100th year

Founding fellow of the Learned Society and its doyen, astronomer doc. RNDr. Luboš Perek, DrSc, is celebrating his 100th birthday on 26 July 2019. He is an indelible part of history as the person who helped define cosmic space, he was the first to point out the issue of cosmic waste and was also a teacher to the most important Czechoslovak astronomers. Let us express our respect and admiration of the extraordinary scientific career of a person who worked tirelessly and continues to work. The Learned Society wishes Mr Perek health, optimism and joy in the oncoming years.


The Academy of Sciences of the Czech Republic has appealed to the Hungarian President to support academic freedom

On Friday 19 July the Academy of Sciences of the Czech Republic and the Learned Society of the Czech Republic sent a letter to Hungarian President János Ánder, in which they state their concerns regarding the situation in respect to management and funding of scientific activities in Hungary. An act, according to which not the Academy of Sciences, but a thirteen-member political committee, will decide on research, funding of scientific activities and establishment or closure of scientific workplaces, will come into force on 1 September.


The loss of Learned Society Fellow prof. Josef Koutecký

We regret to inform that prof. Josef Koutecký, a fellow of the Learned Society, a renowned physician and the founder of paediatric oncology in this country, passed away on 5 July 2019 at the age of 88. He founded paediatric oncology here in 1964 and a separate paediatric oncology department was then established at the Faculty Hospital in Motol, Prague in 1978.