From hubertmingchen at gmail.com Mon Jun 9 11:53:37 2025 From: hubertmingchen at gmail.com (Hubie Chen) Date: Mon, 9 Jun 2025 10:53:37 +0100 Subject: [Proof Complexity] Call for submissions: QBF '25 Message-ID: ==================== International Workshop on Quantified Boolean Formulas and Beyond https://qbf.pages.sai.jku.at/qbf25/ In conjunction with SAT 2025 ==================== =========== Overview =========== Quantified Boolean formulas (QBF) are an extension of propositional logic which allows for explicit quantification over propositional variables. The decision problem of QBF is PSPACE-complete, compared to the NP-completeness of the decision problem of propositional logic (SAT). Many problems from application domains such as model checking, formal verification or synthesis are PSPACE-complete, and hence could be encoded in QBF in a natural way. Considerable progress has been made in QBF solving throughout the past years. However, in contrast to SAT, QBF is not yet widely applied to practical problems in academic or industrial settings. For example, the extraction and validation of models of (un)satisfiability of QBFs has turned out to be challenging, given that state-of-the-art solvers implement different solving paradigms. The goal of the International Workshop on Quantified Boolean Formulas (QBF Workshop) is to bring together researchers working on theoretical and practical aspects of QBF solving and extensions like DQBF. In addition to that, it addresses (potential) users of QBF in order to reflect on the state-of-the-art and to consolidate on immediate and long-term research challenges. The workshop also welcomes work on reasoning with quantifiers in related problems, such as dependency QBF (DQBF), quantified constraint satisfaction problems (QCSP), and satisfiability modulo theories (SMT) with quantifiers. =========== About QBF =========== Continued improvements in the performance of propositional satisfiability (SAT) solvers are enabling a growing number of applications in the area of electronic design automation, such as model checking, synthesis, and symbolic execution. SAT solvers are also a driving force behind recent progress in constrained sampling and counting, and competitive planning tools. In most of these cases, SAT solvers deal with problems from complexity classes beyond NP and propositional encodings that grow super-polynomially in the size of the original instances. Clever techniques such as incremental solving can partly alleviate this issue, but ultimately the underlying asymptotics lead to formulas that are too large to be solved by even the most efficient SAT solvers. This has prompted the development of decision procedures for more succinct generalizations of propositional logic such as Quantified Boolean Formulas (QBFs), which allow for explicit quantification over truth values. The decision problem of QBF is PSPACE-complete, and thus many problems from application domains such as model checking, formal verification or synthesis-which happen to be PSPACE-complete-could be succinctly encoded in QBF. Considerable progress has been made in QBF solving throughout the past years. However, in contrast to SAT, QBF solvers generally do not scale well enough on practically relevant problems arising in an industrial setting. * The main aim of the workshop is to bring together researchers working on QBF theory and solver developers so as to further our theoretical understanding of this hardness and find ways of overcoming it in practice. It provides a forum in which the community can identify immediate and long-term research challenges. That includes (potential) users, which are invited to reflect on the current state-of-the-art and identify obstacles to the adoption of QBF solvers as well as specific problems (instances) for developers to target. * Researchers in other areas of automated reasoning face similar problems in lifting techniques and algorithms for quantifier-free formulas to a quantified version. For instance, this is the case in Quantified Constrained Satisfaction Problems (QCSP), or Sat Modulo Theory (SMT) with quantifiers. This workshop also seeks to promote an exchange of ideas and collaboration between researchers working on QBF and those in other subfields of automated reasoning that deal with quantification. * Recent years have seen research on Dependency QBF (DQBF), which further generalize QBFs by allowing non-linear quantifier prefixes. Given that DQBF evaluation is NEXP-complete, and in view of the difficulties presented by QBF solving, the development of DQBF solvers may seem futile. However, the trade-off between succinctness and complexity offered by DQBF may be favorable in practice. The workshop also aims to be a platform for research on formalisms that go beyond QBF in this way. =========== Submission =========== Submissions of extended abstracts are invited and will be managed via Easychair https://easychair.org/conferences/?conf=qbf25 In particular, we invite the submission of extended abstracts on work that has been published already, novel unpublished work, or work in progress. The following forms of submissions are solicited: * Proposals for short tutorial presentations * Talk abstracts reporting on already published work * Talk proposals presenting work that is unpublished or in progress. Submissions which describe novel applications of QBF or related formalisms in various domains are particularly welcome. Additionally, this call comprises known applications which have been shown to be hard for QBF solvers in the past as well as new applications for which present QBF solvers might lack certain features still to be identified. Each submission should have an overall length of 1-4 pages in LNCS format. Authors may decide to include an appendix with additional material. Appendices will be considered at the reviewers? discretion. The accepted extended abstracts will be published on the workshop webpage. The workshop does not have formal proceedings. Authors of accepted contributions are expected to give a talk at the workshop. There are two submission deadlines. If submitted before the first deadline has passed, the notification will be before the early registration deadline of SAT. =========== Program Committee =========== * Hubie Chen, King's College London * Leroy Chew, TU Wien * Martina Seidl, JKU Linz * Friedrich Slivovsky, Univ. Liverpool =========== Important Dates =========== * June 10: 1st submission deadline (round 1 deadline) * June 22: notification of round 1 * July 10: 2nd submission round (round 2 deadline) * July 22: notification of round 2 * August 11: workshop == Contact qbf25 at easychair.org From jn at di.ku.dk Wed Jun 11 21:01:35 2025 From: jn at di.ku.dk (=?UTF-8?Q?Jakob_Nordstr=C3=B6m?=) Date: Wed, 11 Jun 2025 21:01:35 +0200 Subject: [Proof Complexity] Call for Participation CP/SAT/SoCS 2025 (early-bird rate until 30th June) Message-ID: <1c898e92-7e68-431d-8db8-69666ea10b8b@di.ku.dk> Dear colleagues, For those of us interested in the connection between proof complexity and combinatorial algorithms, there is a pretty unique opportunity to hear more about applied and theoretical research at the 31st International Conference on Principles and Practice of Constraint Programming (CP 2025), the 28th International Conference on Theory and Applications of Satisfiability Testing (SAT 2025), and the 18th International Symposium on Combinatorial Search (SoCS 2025), which will be held together at the University of Glasgow, Scotland, from 12th to 15th August 2025. Alongside the three conferences, we also have a joint CP/SAT doctoral program, as well as a two-day workshop programme on the 10th and 11th August featuring: - the 23rd International Workshop on Satisfiability Modulo Theories (SMT) - the 1st Workshop on Explanations with Constraints and Satisfiability (ExCoS) - Machine Learning for Solvers and Provers (ML4SP) - the 2nd International Workshop on Discrete Optimization with Soft Constraints - LLMs meet Constraint Solving - the 24th workshop on Constraint Modelling and Reformulation (ModRef) - the 16th Pragmatics of SAT international workshop - the Workshop on Counting, Sampling, and Synthesis - the International Workshop on Quantified Boolean Formulas and Beyond - the Eighth Workshop on Progress Towards the Holy Grail (PTHG-25). There is a single, shared registration fee that will give you access to all three conferences and all of the workshops. For details, please see: https://satisfiability.org/SAT25/local/ Early registration rates end on the 30th June. We also recommend booking accommodation well in advance, since the World Pipe Band Championships and the Edinburgh Festival are running at the same time as the conference. Finally, we would like to draw your attention to a related event, the SAT/SMT/AR Summer School, which will also be taking in place in Scotland the week before our conferences: https://sat-smt-ar-school.gitlab.io/www/2025/ Looking forward to seeing you to Glasgow, Jeremias Berg and Jakob Nordstr?m SAT 2025 program committee chairs From jn at di.ku.dk Thu Jun 19 16:48:26 2025 From: jn at di.ku.dk (=?iso-8859-1?Q?Jakob_Nordstr=F6m?=) Date: Thu, 19 Jun 2025 14:48:26 +0000 Subject: [Proof Complexity] Student travel support for CP and SAT 2025 Message-ID: <4a19dedf-9e24-4ef6-9bd9-3476bc6b6762@di.ku.dk> Dear students, You can now apply for financial support for participating in the CP and SAT conferences by going to https://satcpdp25.github.io/ and following the information there. The deadline is 25th June. Note that the application is open also for students not enrolled in the SAT/CP doctoral program. The early-bird rate for registration is available until 30th June, and covers the 31st International Conference on Principles and Practice of Constraint Programming (CP 2025), the 28th International Conference on Theory and Applications of Satisfiability Testing (SAT 2025), and the 18th International Symposium on Combinatorial Search (SoCS 2025). The three conferences will be held together at the University of Glasgow, Scotland, from 12th to 15th August 2025. Alongside the three conferences, we also have a joint CP/SAT doctoral program, as well as a two-day workshop programme on the 10th and 11th August featuring: - the 23rd International Workshop on Satisfiability Modulo Theories (SMT) - the 1st Workshop on Explanations with Constraints and Satisfiability (ExCoS) - Machine Learning for Solvers and Provers (ML4SP) - the 2nd International Workshop on Discrete Optimization with Soft Constraints - LLMs meet Constraint Solving - the 24th workshop on Constraint Modelling and Reformulation (ModRef) - the 16th Pragmatics of SAT international workshop - the Workshop on Counting, Sampling, and Synthesis - the International Workshop on Quantified Boolean Formulas and Beyond - the Eighth Workshop on Progress Towards the Holy Grail (PTHG-25). The single, shared registration fee will give you access to all three conferences and all of the workshops --- see https://satisfiability.org/SAT25/local/ for more details. Looking forward to seeing you in Glasgow, Jeremias Berg and Jakob Nordstr?m SAT 2025 program committee chairs From jn at di.ku.dk Sat Jun 21 10:50:42 2025 From: jn at di.ku.dk (=?UTF-8?Q?Jakob_Nordstr=C3=B6m?=) Date: Sat, 21 Jun 2025 10:50:42 +0200 Subject: [Proof Complexity] Call for contributions: 2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS '25) Message-ID: <9bca816a-66df-4dbd-8e1b-4f7842e0ded8@di.ku.dk> Dear colleagues, This message is a call for contributions to the */2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25)/* on *September 13-14, 2025,* in *Paris. * Please send a message to Jakob Nordstr?m at jn at di.ku.dk if you wish to contribute a presentation on proof logging, certifying algorithms, or verifiably correct results in general for algorithms or problems in combinatorial solving or automated reasoning broadly construed. Presentation slots will be 30 minutes, including time for questions, discussions, and switching speakers. The intention is that contributed talks will be scheduled on Sunday September 14, with Saturday September 13 reserved for longer tutorial-style talks. For more information about the workshop, please see the text below or visit the webpage https://jakobnordstrom.se/WHOOPS25/. We would be most grateful for your assistance in sharing this information with any colleagues for whom this might be of interest. Best regards, Jakob Nordstr?m 2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25) The */2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25)/* will be held on *September 13-14, 2025,* at *Institut Pascal in Orsay* on the outskirts of Paris in coordination with the /EuroProofNet Workshop on Automated Reasoning and Proof Logging /, which is in turn part of the /Final EuroProofNet Symposium /. More information about the workshop can be found at https://jakobnordstrom.se/WHOOPS25/. Please contact Jakob Nordstr?m if you wish to contribute a presentation. Background and Purpose Since the turn of the millennium there have been dramatic improvements in algorithms for combinatorial solving and optimization. The flipside of this is that as the methods get increasingly sophisticated, it becomes increasingly harder to avoid bugs sneaking in during algorithm design and implementation, and even the most mature tools currently available struggle with incorrect results. Software testing, while important, has not been sufficient to resolve this problem, and formal verification methods are far from being able to scale to the level of complexity in modern combinatorial solvers. During the last twenty years the Boolean satisfiability (SAT) solving community has instead spearheaded the use of /proof logging/, meaning that the SAT solvers have to output, along the answer to a problem, a machine-verifiable proof that this answer is correct. Such solvers are also referred to as /certifying algorithms/. For a long time, attempts to extend proof logging to stronger paradigms in combinatorial solving and optimization have met with limited success, but this has changed in the last few years with the introduction of /pseudo-Boolean (PB) proof logging/. Pseudo-Boolean proofs operate with 0-1 integer linear inequalities using a version of the cutting planes proof system, but have turned out to be a very convenient format also for algorithms that reason in terms of very different concepts. The /VeriPB / tool developed by the /Mathematical Insights into Algorithms for Optimization (MIAO) / research group in Copenhagen/Lund and its collaborators has so far been shown to support efficient proof logging for paradigms such as SAT-based optimization (MaxSAT), pseudo-Boolean optimization, subgraph solving, constraint programming, automated planning, and presolving in 0-1 integer linear programming, as well as for techniques such as symmetry breaking and dynamic programming. These developments have been so fast that in 2024 the fairly spontaneous idea arose to gather researchers working on pseudo-Boolean proof logging to an informal gathering, which?reflecting the rather improvised nature of the event?was named the /1st Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'24)/ . This year, the second edition of the workshop will be held on September 13-14 in Orsay outside Paris under the auspices of EuroProofNet . While we still expect a healthy dose of pseudo-Boolean proof logging, we are very much hoping to also discuss certifying algorithms for automated reasoning more broadly, including satisfiability modulo theories (SMT) solving and first- and higher-order theorem proving. Registration Registration is free but mandatory, and is done by filling in the registration form . Workshop Program More information about the program will be available closer to the workshop at https://jakobnordstrom.se/WHOOPS25/. The tentative plans are that: * Saturday will consist of slightly longer, tutorial-style, talks, explaining how pseudo-Boolean proof logging can support efficient certified solving for paradigms such as SAT-based optimization (MaxSAT), pseudo-Boolean optimization, subgraph solving, constraint programming, automated planning, as well as for techniques such as symmetry breaking and dynamic programming. * On Sunday we will have contributed talks, where we might still have some presentations of the very latest news in pseudo-Boolean proof logging, but where we are very much hoping to also discuss certifying algorithms for automated reasoning more broadly, including satisfiability modulo theories (SMT) solving and first- and higher-order theorem proving. /Please contact Jakob Nordstr?m if you would be interested in giving a presentation at the WHOOPS?'25 workshop. / Jakob Nordstr?m, Professor University of Copenhagen and Lund University Phone: +45 28 78 38 11 / +46 70 742 21 98 https://jakobnordstrom.se/ / From jn at di.ku.dk Sat Jun 21 10:53:10 2025 From: jn at di.ku.dk (=?UTF-8?Q?Jakob_Nordstr=C3=B6m?=) Date: Sat, 21 Jun 2025 10:53:10 +0200 Subject: [Proof Complexity] Call for contributions: 2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS '25) Message-ID: Dear colleagues, This message is a call for contributions to the */2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25)/* on *September 13-14, 2025,* in *Paris. * Please send a message to Jakob Nordstr?m at jn at di.ku.dk if you wish to contribute a presentation on proof logging, certifying algorithms, or verifiably correct results in general for algorithms or problems in combinatorial solving or automated reasoning broadly construed. Presentation slots will be 30 minutes, including time for questions, discussions, and switching speakers. The intention is that contributed talks will be scheduled on Sunday September 14, with Saturday September 13 reserved for longer tutorial-style talks. For more information about the workshop, please see the text below or visit the webpage https://jakobnordstrom.se/WHOOPS25/. We would be most grateful for your assistance in sharing this information with any colleagues for whom this might be of interest. Best regards, Jakob Nordstr?m 2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25) The */2nd International Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'25)/* will be held on *September 13-14, 2025,* at *Institut Pascal in Orsay* on the outskirts of Paris in coordination with the /EuroProofNet Workshop on Automated Reasoning and Proof Logging /, which is in turn part of the /Final EuroProofNet Symposium /. More information about the workshop can be found at https://jakobnordstrom.se/WHOOPS25/. Please contact Jakob Nordstr?m if you wish to contribute a presentation. Background and Purpose Since the turn of the millennium there have been dramatic improvements in algorithms for combinatorial solving and optimization. The flipside of this is that as the methods get increasingly sophisticated, it becomes increasingly harder to avoid bugs sneaking in during algorithm design and implementation, and even the most mature tools currently available struggle with incorrect results. Software testing, while important, has not been sufficient to resolve this problem, and formal verification methods are far from being able to scale to the level of complexity in modern combinatorial solvers. During the last twenty years the Boolean satisfiability (SAT) solving community has instead spearheaded the use of /proof logging/, meaning that the SAT solvers have to output, along the answer to a problem, a machine-verifiable proof that this answer is correct. Such solvers are also referred to as /certifying algorithms/. For a long time, attempts to extend proof logging to stronger paradigms in combinatorial solving and optimization have met with limited success, but this has changed in the last few years with the introduction of /pseudo-Boolean (PB) proof logging/. Pseudo-Boolean proofs operate with 0-1 integer linear inequalities using a version of the cutting planes proof system, but have turned out to be a very convenient format also for algorithms that reason in terms of very different concepts. The /VeriPB / tool developed by the /Mathematical Insights into Algorithms for Optimization (MIAO) / research group in Copenhagen/Lund and its collaborators has so far been shown to support efficient proof logging for paradigms such as SAT-based optimization (MaxSAT), pseudo-Boolean optimization, subgraph solving, constraint programming, automated planning, and presolving in 0-1 integer linear programming, as well as for techniques such as symmetry breaking and dynamic programming. These developments have been so fast that in 2024 the fairly spontaneous idea arose to gather researchers working on pseudo-Boolean proof logging to an informal gathering, which?reflecting the rather improvised nature of the event?was named the /1st Workshop on Highlights in Organizing and Optimizing Proof-logging Systems (WHOOPS?'24)/ . This year, the second edition of the workshop will be held on September 13-14 in Orsay outside Paris under the auspices of EuroProofNet . While we still expect a healthy dose of pseudo-Boolean proof logging, we are very much hoping to also discuss certifying algorithms for automated reasoning more broadly, including satisfiability modulo theories (SMT) solving and first- and higher-order theorem proving. Registration Registration is free but mandatory, and is done by filling in the registration form . Workshop Program More information about the program will be available closer to the workshop at https://jakobnordstrom.se/WHOOPS25/. The tentative plans are that: * Saturday will consist of slightly longer, tutorial-style, talks, explaining how pseudo-Boolean proof logging can support efficient certified solving for paradigms such as SAT-based optimization (MaxSAT), pseudo-Boolean optimization, subgraph solving, constraint programming, automated planning, as well as for techniques such as symmetry breaking and dynamic programming. * On Sunday we will have contributed talks, where we might still have some presentations of the very latest news in pseudo-Boolean proof logging, but where we are very much hoping to also discuss certifying algorithms for automated reasoning more broadly, including satisfiability modulo theories (SMT) solving and first- and higher-order theorem proving. /Please contact Jakob Nordstr?m if you would be interested in giving a presentation at the WHOOPS?'25 workshop. / Jakob Nordstr?m, Professor University of Copenhagen and Lund University Phone: +45 28 78 38 11 / +46 70 742 21 98 https://jakobnordstrom.se/ / From amir.akbar at gmail.com Thu Jun 26 16:03:44 2025 From: amir.akbar at gmail.com (Amir Tabatabai) Date: Thu, 26 Jun 2025 16:03:44 +0200 Subject: [Proof Complexity] A Survey on Proof Complexity Message-ID: Dear all, I have recently written a chapter on proof complexity and its connection to interpolation, available here: https://arxiv.org/abs/2505.03002 This chapter will appear in the forthcoming book "Theory and Applications of Craig Interpolation", edited by Balder ten Cate, Jean Christoph Jung, Patrick Koopmann, Christoph Wernhard, and Frank Wolter. The chapter serves as a survey of the basics of propositional proof complexity, both classical and non-classical, with a particular emphasis on the use of feasible interpolation to establish hardness results. It is intended to be accessible to a broader audience familiar with proof theory, though not necessarily with proof complexity. I assume only a basic familiarity with propositional, modal, and first-order logic, as well as foundational concepts from computational complexity, such as the complexity classes NP and PSPACE. Any additional notions are introduced and explained as needed. I would greatly appreciate any comments, suggestions, corrections, or general feedback you may have. Best wishes, Amir. From Giovanni.Solda at UGent.be Mon Jun 30 20:28:49 2025 From: Giovanni.Solda at UGent.be (Giovanni Solda) Date: Mon, 30 Jun 2025 18:28:49 +0000 Subject: [Proof Complexity] CfR: Proof Society Summer School and Workshop, Ghent (Belgium), 1-5 September 2025 Message-ID: The 7th International School and Workshop on Proof Theory will be organized by Ghent University under the auspices of The Proof Society. This annual event continues its tradition of uniting students, researchers, and practitioners to explore both the applied and foundational aspects of proof theory. Following the format of previous editions, the event begins with a three-day Summer School (September 1?3) offering five tutorials on a variety of topics related to proof theory. This will be followed by a two-day Workshop (September 4?5) featuring invited lectures and contributed talks. Guided by The Proof Manifesto, this event embraces the notion of proofs in its broadest sense, welcoming participation and contributions from logic, computer science, mathematics, and beyond. More information can be found on the website: https://proof2025.ugent.be/ IMPORTANT DATES * Notification of acceptance for submitted abstracts: 14th of July * Registration deadline: 31st of July * Summer School: 1st to 3rd of September * Workshop: 4th and 5th of September REGISTRATION Registration is now open. The fees are: * Summer School (regular): 150 euros * Summer School (students): 100 euros * Workshop (regular): 150 euros * Workshop (students): 100 euros * Social dinner: 40 euros * Excursion: 20 euros Further information (and discounts for Flemish students) can be found on the conference website. BEST STUDENT PRESENTATION AWARD As is traditional for the proof Society Workshop, there will be an award for the best student presentation. TUTORIAL SPEAKERS FOR THE SUMMER SCHOOL * Mohammad Ardeshir * Ali Enayat * Raheleh Jalali * Henry Towsner * Albert Visser INVITED SPEAKERS FOR THE WORKSHOP * Juan Pablo Aguilera * Toshiyasu Arai * Iris van der Giessen * Anton Setzer * Arnold Beckmann, who will give a talk in memoriam of Wolfram Pohlers PROGRAM COMMITTEE * Fedor Pakhomov * Bahereh Afshari * Lev Beklemishev * Benno van den Berg * Lorenzo Carlucci * David Fern?ndez-Duque * Balthasar Grabmayr * Stefan Hetzl * Jan Heylen * Rosalie Iemhoff * Mateusz ?e?yk * Maria Emilia Maietti * Nicholas Pischke * Takako Nemoto * Monika Seisenberger * Johannes Stern ORGANIZING COMMITTEE * Andreas Weiermann * Fedor Pakhomov * Giovanni Sold? * Mojtaba Mojtahedi * Brett McLean * Alakh Dhruv Chopra * Philipp Provenzano * Lukas Matthias Zenger * Vlad Lazar * Jan Heylen * Daisie Job Rock * Jozefien D?haeseleer * Morgan Callewaert * Joke Meheus