BEGIN:VCALENDAR
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PRODID:researchseminars.org
CALSCALE:GREGORIAN
X-WR-CALNAME:researchseminars.org
BEGIN:VEVENT
SUMMARY:Joost-Pieter Katoen (RWTH Aachen University)
DTSTART:20200415T130000Z
DTEND:20200415T140000Z
DTSTAMP:20260404T110823Z
UID:OWLS/1
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 1/">Termination of probabilistic programs</a>\nby Joost-Pieter Katoen (RWT
 H Aachen University) as part of Online Worldwide Seminar on Logic and Sema
 ntics (OWLS)\n\n\nAbstract\nProgram termination is a key question in progr
 am verification. This talk considers the termination of probabilistic prog
 rams\, programs that can describe randomised algorithms and more recently 
 received attention in machine learning. Probabilistic termination has seve
 ral nuances and has some unexpected effects. Programs may diverge with zer
 o probability\; they almost-surely terminate (AST). Two AST-programs run i
 n sequence may have an infinite expected run-time\, though each of its con
 stituents has a finite expected run-time.\n\nThis talk will demystify the 
 notions of probabilistic termination\, its surprising effects\, and its ha
 rdness ("degree of undecidability"). We will show a simple proof rule for 
 deciding AST.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/1/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Daniela Petrisan (University of Paris)
DTSTART:20200429T130000Z
DTEND:20200429T140000Z
DTSTAMP:20260404T110823Z
UID:OWLS/2
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 2/">Combining probabilistic and non-deterministic choice via weak distribu
 tive laws</a>\nby Daniela Petrisan (University of Paris) as part of Online
  Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/2/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Bartek Klin (University of Warsaw)
DTSTART:20200513T130000Z
DTEND:20200513T140000Z
DTSTAMP:20260404T110823Z
UID:OWLS/3
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 3/">Monadic monadic second order logic</a>\nby Bartek Klin (University of 
 Warsaw) as part of Online Worldwide Seminar on Logic and Semantics (OWLS)\
 n\n\nAbstract\nMonadic second order logic (MSO) is usually studied over sp
 ecific kinds of structures\, be it finite words\, infinite words\, finite 
 or infinite trees\, total orders of various shapes\, etc. A monad is a not
 ion of "a kind of structures" that covers these and many other examples. O
 ne can formulate an abstract definition of MSO for a generic monad. I will
  explain how this is done\, and I will describe some conditions that a mon
 ad should satisfy to ensure a basic "sanity check": that every definable l
 anguage is recognized by a finite algebra.\n\n(joint work with Mikołaj Bo
 jańczyk and Julian Salamanca)\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/3/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dexter Kozen (Cornell University)
DTSTART:20200527T130000Z
DTEND:20200527T140000Z
DTSTAMP:20260404T110823Z
UID:OWLS/4
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 4/">Brzozowski derivatives as distributive laws</a>\nby Dexter Kozen (Corn
 ell University) as part of Online Worldwide Seminar on Logic and Semantics
  (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/4/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Valeria Vignudelli (ENS Lyon)
DTSTART:20200610T130000Z
DTEND:20200610T140000Z
DTSTAMP:20260404T110823Z
UID:OWLS/5
DESCRIPTION:by Valeria Vignudelli (ENS Lyon) as part of Online Worldwide S
 eminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/5/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ryoma Sin'ya (Akita University)
DTSTART:20200930T140000Z
DTEND:20200930T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/6
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 6/">Asymptotic Approximation by Regular Languages (YR-OWLS)</a>\nby Ryoma 
 Sin'ya (Akita University) as part of Online Worldwide Seminar on Logic and
  Semantics (OWLS)\n\n\nAbstract\nIn this talk we will introduce a new prop
 erty of formal languages called REG-measurability where REG is the class o
 f regular languages. Intuitively\, a language L is REG-measurable if there
  exists an infinite sequence of regular languages that ``converges'' to L.
  A language without REG-measurability has a complex shape in some sense so
  that it can not be approximated by regular languages.\n\nThe motivation\,
  why we have been interested in REG-measurability\, originally came from t
 he following conjecture posed by [Dömösi-Horvath-Ito 1991]: the set of a
 ll primitive words over a non-singleton alphabet is not context-free.\n\nW
 e will describe that several context-free languages are REG-measurable (in
 cluding languages with transcendental generating function and transcendent
 al density\, in particular)\, while a certain simple deterministic context
 -free language and the set of primitive words are REG-immeasurable in a st
 rong sense. We will also discuss some open problems and future work.\nThis
  talk is based on the following work: http://www.math.akita-u.ac.jp/~ryoma
 /misc/measure.pdf\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/6/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andrej Bauer (University of Ljubljana)
DTSTART:20201007T140000Z
DTEND:20201007T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/7
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 7/">Effects in the real world</a>\nby Andrej Bauer (University of Ljubljan
 a) as part of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\n\n
 Abstract\nJoint work with Danel Ahman\, University of Ljubljana (https://d
 anel.ahman.ee/).\n\nIn modern languages\, computational effects are often 
 structured using monads or algebraic effects and handlers. These mechanism
 s excel at implementation of computational effects within the language its
 elf. For instance\, the familiar implementation of mutable state in terms 
 of state-passing functions requires no native state\, and can be implement
 ed either as a monad or using handlers. One is naturally drawn to using th
 ese techniques also for dealing with actual effects\, such as manipulation
  of native memory and access to hardware. These are represented inside the
  language as algebraic operations or a monad\, but treated specially by th
 e language's top-level runtime\, which invokes corresponding operating sys
 tem functionality. While this approach works in practice\, one wishes that
  the ingenuity of the language implementors were better supported by a mor
 e flexible methodology with a sound theoretical footing.\n\nWe address the
  issue by showing how to design a programming language based on runners of
  algebraic effects. We review runners\, recast them as a programming const
 ruct\, and present a calculus that captures the core ideas of programming 
 with them. Through examples of runners we show how they capture both the i
 nteraction between the program and the external world\, and encapsulation 
 of programs in virtual environments that tightly control access to externa
 l resources and provide strong guarantees of proper resource finalization.
 \n\nWe accompanied our work with a prototype programming language Coop (ht
 tps://github.com/andrejbauer/coop) and a Haskell library for runners (http
 s://github.com/danelahman/haskell-coop).\n\nReferences:\n\n - https://arxi
 v.org/abs/1910.11629\n\n - https://github.com/andrejbauer/coop\n\n - https
 ://github.com/danelahman/haskell-coop\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/7/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Henning Basold (Universteit Leiden)
DTSTART:20201014T140000Z
DTEND:20201014T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/8
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 8/">Coalgebraic Communication Protocols and Session Types (YR-OWLS)</a>\nb
 y Henning Basold (Universteit Leiden) as part of Online Worldwide Seminar 
 on Logic and Semantics (OWLS)\n\n\nAbstract\nThis is joint work with Alex 
 Keizer and Jorge A. Pérez.\n\nCompositional methods are central to the de
 velopment and verification of software systems. They allow to break down l
 arge systems into smaller components\, while enabling reasoning about the 
 behaviour of the composed system. For concurrent and communicating systems
 \, compositional techniques based on *behavioural type systems* have recei
 ved much attention. By abstracting communication protocols as types\, thes
 e type systems can statically check that programs interact with channels a
 ccording to a certain protocol\, whether the intended messages are exchang
 ed in a certain order. For this talk\, we will put on our coalgebraic spec
 tacles to investigate *session types*\, a widely studied class of behavior
 al type systems. We will seek a syntax-free description of session-based c
 oncurrency as states of coalgebras. The result will be a description of ty
 pe equivalence\, duality\, and subtyping relations in terms of canonical c
 oinductive presentations. In turn\, this coinductive presentation makes it
  possible to elegantly derive a decidable type system with subtyping for 
 π-calculus processes\, in which the states of a coalgebra will serve as c
 hannel protocols. Going full circle\, we will also exhibit a coalgebra str
 ucture on an existing session type system\, and show that the relations an
 d type system resulting from our coalgebraic perspective agree with the ex
 isting ones.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/8/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Antonin Kucera (Masaryk University)
DTSTART:20201021T140000Z
DTEND:20201021T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/9
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 9/">Efficient analysis of VASS termination complexity</a>\nby Antonin Kuce
 ra (Masaryk University) as part of Online Worldwide Seminar on Logic and S
 emantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/9/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sebastian Junges (UC Berkeley)
DTSTART:20201028T140000Z
DTEND:20201028T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/10
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 10/">Finding Memoryless Policies in Partially Observable MDPs is ETR-compl
 ete (YR-OWLS)</a>\nby Sebastian Junges (UC Berkeley) as part of Online Wor
 ldwide Seminar on Logic and Semantics (OWLS)\n\n\nAbstract\nPartially obse
 rvable Markov Decision Processes (POMDPs) are a prime model in sequential 
 decision making. They are heavily studied in operations research\, artific
 ial intelligence and verification\, to name a few. For POMDPs\, a good pol
 icy reaches the target with probability at some threshold\, and makes its 
 decisions solely based on the previously made observations. Deciding wheth
 er a good policy exists is undecidable. One of the methods to solve instan
 ces of this reachability problem is to restrict the memory that the strate
 gy may use. This approach is commonly taking\, e.g.\, in reinforcement lea
 rning for POMDPs. In the first part of the talk\, we consider memoryless s
 trategies in POMDPs. and show that this problem is as hard as the feasibil
 ity problem in parametric Markov Chain (pMC) analysis.\n\nIn the second pa
 rt of the talk\, we consider this feasibility problem for pMCs. Roughly\, 
 a pMC is a Markov chain with symbolic transitions. The feasibility problem
  asks: Do values for the symbols exist such that in the induced parameter-
 free Markov chain\, a target state is reached with probability at least a 
 half. We discuss the complexity landscape for variants of this decision pr
 oblem. In particular\, we establish that feasibility in pMCs is complete f
 or the complexity class "existential theory of the reals” (ETR). Another
  example of an ETR-complete problem is deciding whether a multivariate pol
 ynomial has a real root. Together with the results of the first half of th
 e talk\, this establishes that deciding whether there exists a good memory
 less policy in a POMDP is ETR-complete.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/10/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Orna Kupferman (Hebrew University)
DTSTART:20201104T140000Z
DTEND:20201104T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/11
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 11/">Examining Classical Graph-Theory Problems from the Viewpoint of Forma
 l-Verification Methods</a>\nby Orna Kupferman (Hebrew University) as part 
 of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\n\nAbstract\nT
 he talk surveys a series of works that lift the rich semantics and structu
 re of graphs\, and the experience of the formal-verification community in 
 reasoning about them\, to classical graph-theoretical problems.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/11/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joël Ouaknine (Max Planck Institute for Software Systems)
DTSTART:20201118T140000Z
DTEND:20201118T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/12
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 12/">Holonomic Techniques\, Periods\, and Decision Problems</a>\nby Joël 
 Ouaknine (Max Planck Institute for Software Systems) as part of Online Wor
 ldwide Seminar on Logic and Semantics (OWLS)\n\n\nAbstract\nHolonomic tech
 niques have deep roots going back to Wallis\, Euler\, and Gauss\, and have
  evolved in modern times as an important subfield of computer algebra\, th
 anks in large part to the work of Zeilberger and others over the past thre
 e decades. In this talk\, I will give an overview of the area\, and in par
 ticular will present a select survey of known and original results on deci
 sion problems for holonomic sequences and functions. I will also discuss s
 ome surprising connections to the theory of periods and exponential period
 s\, which are classical objects of study in algebraic geometry and number 
 theory\; in particular\, I will relate the decidability of certain decisio
 n problems for holonomic sequences to deep conjectures about periods and e
 xponential periods\, notably those due to Kontsevich and Zagier.\n\nParts 
 of this talk will be based on the paper "On Positivity and Minimality for 
 Second-Order Holonomic Sequences"\, https://arxiv.org/abs/2007.12282.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/12/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Francesco Gavazzo (University of Bologna)
DTSTART:20201125T140000Z
DTEND:20201125T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/13
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 13/">Modal Reasoning = Metric Reasoning\, via Lawvere (YR-OWLS)</a>\nby Fr
 ancesco Gavazzo (University of Bologna) as part of Online Worldwide Semina
 r on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/13/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Derek Dreyer (Max Planck Institute for Software Systems)
DTSTART:20201209T140000Z
DTEND:20201209T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/14
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 14/">Turning Iris Up to Eleven: Next Steps in Higher-Order Separation Logi
 c</a>\nby Derek Dreyer (Max Planck Institute for Software Systems) as part
  of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\n\nAbstract\n
 Iris is a framework for higher-order concurrent separation logic\, impleme
 nted in the Coq proof assistant\, which we have been developing since 2014
 . Originally designed for pedagogical purposes\, Iris has grown into a ong
 oing\, multi-institution project\, with active collaborators at Aarhus Uni
 versity\, BedRock Systems\, Boston College\, CNRS/LRI\, Groningen Universi
 ty\, INRIA\, ITU Copenhagen\, KU Leuven\, Microsoft Research\, MIT\, MPI-S
 WS\, NYU\, Radboud University Nijmegen\, Saarland University\, and Vrije U
 niversiteit Brussel\, and over 35 published papers studying or deploying I
 ris for verification of complex programs and programming language meta-the
 ory in Rust\, Go\, OCaml\, Scala\, and more (https://iris-project.org).\n\
 nIn this talk\, we will present two brand new -- and very different -- dev
 elopments that have the potential to extend the reach of Iris even further
 . The first is a new *ownership-based refinement type system* for C\, whic
 h supports *automated* verification of C programs while at the same time b
 eing *foundational* (producing Iris proofs in Coq). The second is a comple
 te "remodeling" of Iris\, replacing its original step-indexed model with a
  *transfinite* step-indexed model in order to make Iris suitable for verif
 ication of liveness properties.\n\nFor this talk\, we will not assume any 
 prior knowledge of Iris. Rather\, we will briefly review the distinguishin
 g features of Iris\, and then explain the key insights behind the aforemen
 tioned new developments -- and the problems they are solving -- at a high 
 level of abstraction.\n\nThe first new development is joint work with Mich
 ael Sammler\, Rodolphe Lepigre\, Robbert Krebbers\, Kayvan Memarian\, and 
 Deepak Garg. The second is joint work with Simon Spies\, Lennard Gäher\, 
 Daniel Gratzer\, Joseph Tassarotti\, Robbert Krebbers\, and Lars Birkedal.
 \n
LOCATION:https://stable.researchseminars.org/talk/OWLS/14/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Maaike Zwart (University of Oxford)
DTSTART:20201202T140000Z
DTEND:20201202T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/15
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 15/">Distributive Laws in the Boom Hierarchy (YR-OWLS)</a>\nby Maaike Zwar
 t (University of Oxford) as part of Online Worldwide Seminar on Logic and 
 Semantics (OWLS)\n\n\nAbstract\nDuring my PhD research I have studied dist
 ributive laws for monads\, and developed various no-go theorems. These the
 orems prove that monads with certain algebraic properties cannot be compos
 ed with each other via a distributive law. In this talk I will focus on ex
 amples\, and share the intuition that I have developed from my results. Al
 l the examples in this talk will be based on the Boom hierarchy\, a hierar
 chy of data structures which lends itself perfectly for the study of monad
  compositions. Based on which monads in this hierarchy do and do not compo
 se with each other via a distributive law\, I will make predictions about 
 the behaviour of monad compositions in general.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/15/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Abhisekh Sankaran (University of Cambridge)
DTSTART:20201111T140000Z
DTEND:20201111T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/16
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 16/">Extension preservation in the finite and prefix classes of first orde
 r logic</a>\nby Abhisekh Sankaran (University of Cambridge) as part of Onl
 ine Worldwide Seminar on Logic and Semantics (OWLS)\n\n\nAbstract\nIt is w
 ell known that the classic Łoś-Tarski preservation theorem fails in the 
 finite: there are first-order definable classes of finite structures close
 d under extensions which are not definable (in the finite) in the existent
 ial fragment of first-order logic. We strengthen this by constructing for 
 every n\, first-order definable classes of finite structures closed under 
 extensions which are not definable with n quantifier alternations. The cla
 sses we construct are definable in the extension of Datalog with negation 
 and indeed in the existential fragment of transitive-closure logic. This a
 nswers negatively an open question posed by Rosen and Weinstein.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/16/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Moshe Vardi (Rice University)
DTSTART:20201216T140000Z
DTEND:20201216T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/17
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 17/">Lessons from COVID-19: Efficiency vs Resilience</a>\nby Moshe Vardi (
 Rice University) as part of Online Worldwide Seminar on Logic and Semantic
 s (OWLS)\n\n\nAbstract\nIn both computer science and economics\, efficienc
 y is a cherished property. In computer science\, the field of algorithms i
 s almost solely focused on their efficiency. In economics\, the main advan
 tage of the free market is that it promises "economic efficiency." A major
  lesson from COVID-19 is that both fields have over-emphasized efficiency 
 and under-emphasized resilience. I argue that resilience is a more importa
 nt property than efficiency and discuss how the two fields can broaden the
 ir focus to make resilience a primary consideration. I will include a tech
 nical example\, showing how we can shift the focus in strategic reasoning 
 from efficiency to resilience.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/17/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sarah Winter (Université libre de Bruxelles)
DTSTART:20210106T140000Z
DTEND:20210106T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/18
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 18/">Synthesizing computable functions from synchronous specifications</a>
 \nby Sarah Winter (Université libre de Bruxelles) as part of Online World
 wide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/18/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Ori Lahav (School of Computer Science at Tel Aviv University)
DTSTART:20210120T140000Z
DTEND:20210120T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/19
DESCRIPTION:by Ori Lahav (School of Computer Science at Tel Aviv Universit
 y) as part of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAb
 stract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/19/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Sonia Marin (University College London)
DTSTART:20210203T140000Z
DTEND:20210203T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/20
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 20/">From axioms to synthetic inference rules via focusing</a>\nby Sonia M
 arin (University College London) as part of Online Worldwide Seminar on Lo
 gic and Semantics (OWLS)\n\n\nAbstract\nFocusing is a general technique th
 at was designed to improve proof search\, but has since become increasingl
 y relevant in structural proof theory. The essential idea is to identify a
 nd merge the non-deterministic choices in a proof. A focused proof is then
  given by the alternation of phases where invertible rules are applied eag
 erly (bottom-up) and phases where the other rules are confined and control
 led. The focusing theorem\, which asserts the completeness of focused proo
 fs\, delivers strong representational benefits. For instance\, by ignoring
  the internal structure of the phases one obtains a well-behaved notion of
  ‘synthetic rule’ (e.g. they commute with cut-reduction steps). In thi
 s talk\, we will present a careful study of a family of synthetic rules\, 
 the bipoles\, giving a fresh view to an old problem: how to incorporate in
 ference rules corresponding to axioms into proof systems for classical and
  intuitionistic logics. As different synthetic inference rules can be prod
 uced for the same axiom\, we in fact unify and generalise previous approac
 hes for transforming axioms into rules. This is joint work with Dale Mille
 r\, Elaine Pimentel\, and Marco Volpe.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/20/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Benjamin Kaminski (University College London)
DTSTART:20210217T140000Z
DTEND:20210217T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/21
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 21/">Quantitative Separation Logic</a>\nby Benjamin Kaminski (University C
 ollege London) as part of Online Worldwide Seminar on Logic and Semantics 
 (OWLS)\n\n\nAbstract\nWe present quantitative separation logic (QSL). In c
 ontrast to classical separation logic\, QSL employs quantities which evalu
 ate to real numbers instead of predicates which evaluate to Boolean values
 . The connectives of classical separation logic\, separating conjunction a
 nd separating implication\, are lifted from predicates to quantities. This
  extension is conservative: Both connectives are backward compatible to th
 eir classical analogs and obey the same laws\, e.g. modus ponens\, adjoint
 ness\, etc. Furthermore\, we present a weakest precondition calculus for q
 uantitative reasoning about probabilistic pointer programs in QSL. This ca
 lculus is a conservative extension of both Ishtiaq's\, O'Hearn's and Reyno
 lds' separation logic for heap-manipulating programs and Kozen's / McIver 
 and Morgan's weakest preexpectations for probabilistic programs. Our calcu
 lus preserves O'Hearn's frame rule\, which enables local reasoning - a key
  principle of separation logic. Finally\, we briefly touch upon open quest
 ions regarding lower bounds on weakest preexpectations and intensional com
 pleteness of our calculus.\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/21/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Tiziano Dalmonte (TU Wien)
DTSTART:20210331T140000Z
DTEND:20210331T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/22
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 22/">Proof systems and countermodels for non-normal modal logics</a>\nby T
 iziano Dalmonte (TU Wien) as part of Online Worldwide Seminar on Logic and
  Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/22/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Jorge Perez (University of Groningen)
DTSTART:20210224T140000Z
DTEND:20210224T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/23
DESCRIPTION:by Jorge Perez (University of Groningen) as part of Online Wor
 ldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/23/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Dale Miller (Inria and LIX\, Ecole Polytechnique)
DTSTART:20210310T140000Z
DTEND:20210310T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/24
DESCRIPTION:by Dale Miller (Inria and LIX\, Ecole Polytechnique) as part o
 f Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\
 n
LOCATION:https://stable.researchseminars.org/talk/OWLS/24/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Anca Muscholl (Université Bordeaux)
DTSTART:20210324T140000Z
DTEND:20210324T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/25
DESCRIPTION:by Anca Muscholl (Université Bordeaux) as part of Online Worl
 dwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/25/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Assia Mahboubi (Inria and Vrije Universiteit Amsterdam)
DTSTART:20210407T140000Z
DTEND:20210407T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/26
DESCRIPTION:by Assia Mahboubi (Inria and Vrije Universiteit Amsterdam) as 
 part of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract
 : TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/26/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Alessio Guglielmi (University of Bath)
DTSTART:20210505T140000Z
DTEND:20210505T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/27
DESCRIPTION:by Alessio Guglielmi (University of Bath) as part of Online Wo
 rldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/27/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Pierre Ohlmann (Université de Paris)
DTSTART:20210317T140000Z
DTEND:20210317T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/28
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 28/">Controlling a random population</a>\nby Pierre Ohlmann (Université d
 e Paris) as part of Online Worldwide Seminar on Logic and Semantics (OWLS)
 \n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/28/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Joshua Moerman (RWTH Aachen)
DTSTART:20210414T140000Z
DTEND:20210414T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/29
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 29/">Weighted Register Automata</a>\nby Joshua Moerman (RWTH Aachen) as pa
 rt of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: 
 TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/29/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Andy Pitts (Cambridge)
DTSTART:20210421T140000Z
DTEND:20210421T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/30
DESCRIPTION:Title: <a href="https://stable.researchseminars.org/talk/OWLS/
 30/">Constructive Initial Algebra Semantics</a>\nby Andy Pitts (Cambridge)
  as part of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbst
 ract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/30/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Fabio Zanasi (UCL London)
DTSTART:20210428T140000Z
DTEND:20210428T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/31
DESCRIPTION:by Fabio Zanasi (UCL London) as part of Online Worldwide Semin
 ar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/31/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Masaki Waga (Kyoto University)
DTSTART:20210512T140000Z
DTEND:20210512T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/32
DESCRIPTION:by Masaki Waga (Kyoto University) as part of Online Worldwide 
 Seminar on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/32/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Gabriel Scherer (INRIA)
DTSTART:20210526T140000Z
DTEND:20210526T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/33
DESCRIPTION:by Gabriel Scherer (INRIA) as part of Online Worldwide Seminar
  on Logic and Semantics (OWLS)\n\nAbstract: TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/33/
END:VEVENT
BEGIN:VEVENT
SUMMARY:Adwait Godbole (University of California at Berkeley)
DTSTART:20210609T140000Z
DTEND:20210609T150000Z
DTSTAMP:20260404T110823Z
UID:OWLS/34
DESCRIPTION:by Adwait Godbole (University of California at Berkeley) as pa
 rt of Online Worldwide Seminar on Logic and Semantics (OWLS)\n\nAbstract: 
 TBA\n
LOCATION:https://stable.researchseminars.org/talk/OWLS/34/
END:VEVENT
END:VCALENDAR
