Workshop affiliated with LICS,
as part of FLOC.
DaLí  Dynamic Logic: new trends and applications
NOW AN ONLINE EVENT
31 July and 1 August 2022
Slides of the talks are now available: just click on the title of the corresponding talk to see the slides!
Alternatively, click here for downloading a zip file.
Overview
Dynamic logic (DL), a generalisation of the logic of FloydHoare introduced in the 70s by Pratt,
is a wellknown and particularly powerful way of combining propositions, for capturing static properties
of program states, and structured actions, responsible for transitions from a state to another (and typically
combined through a Kleene algebra to express sequential, nondeterministic, iterative behaviour of systems),
into a formal framework to reason about, and verify, classic imperative programs.
Over time Dynamic logic grew to encompass a family of logics increasingly popular in the verification of
computational systems, and able to evolve and adapt to new, and complex validation challenges.
In particular, the dynamic logic community is interested in the study of operators that can modify the
structure in which they are being evaluated. Examples include dynamic logics tailored to specific programming
problems or paradigms (e.g., separation logics to model the evolution of a program heap); languages to
reason and represent evolving information (e.g., dynamic epistemic logics); and formalism that aim to model
new computing domains, including probabilistic, continuous and quantum computation.
Dynamic logic is not only theoretically relevant, but it also shows enormous practical potential and it is indeed
a topic of interest in several scientific venues, from widescope
software engineering conferences to modal logic specific events. That being said, DaLí is the only event exclusively
dedicated to this topic. It is our aim to once again bring together in a single place the heterogeneous
community of colleagues which share an interest in Dynamic logic  from Academia to Industry,
from Mathematics to Computer Science,  to promote their works,
to foster great discussions and new collaborations.
Invited talks
 Marta Bílková (Institute of Computer Science, Czech Academy of Sciences, CZ):
Belnapian logics for uncertainty
Reasoning about information, its potential incompleteness, uncertainty,
and contradictoriness need to be dealt with adequately. While
incompleteness and uncertainty are typically accommodated within one
formalism, e.g. within various models of imprecise probability,
contradictoriness and uncertainty less so  conflict or
contradictoriness of information is rather chosen to be resolved than to
be reasoned with. To reason with conflicting information, positive and
negative support  evidence in favour and evidence against  a
statement are quantified separately in the semantics. This
twodimensionality gives rise to logics interpreted over twistproduct
algebras or bilattices, the well known BelnapDunn logic of First
Degree Entailment being a prominent example. BelnapDunn logic with its
doublevaluation frame semantics can in turn be taken as a base logic
for defining various uncertainty measures on de Morgan algebras, e.g.
Belnapian (nonstandard) probabilities or belief functions.
In spirit similar to BelnapDunn logic, we have introduced manyvalued
logics suitable to reason about such uncertainty measures. They are
interpreted over twistproduct algebras based on the [0,1] real interval
as their standard semantics and can be seen to account for the
twodimensionality of positive and negative component of (the degree of)
belief or likelihood based on potentially contradictory information,
quantified by an uncertainty measure. The logics presented in this talk
include expansions of Łukasiewicz with a deMorgan negation which swaps
between the positive and negative semantical component.
Our main objective is to utilise apparatus of twolayered logics to
formalise reasoning with uncertain information, which itself might be
nonclassical, i.e., incomplete or contradictory. Manyvalued logics
with a twodimensional semantics mentioned above are used on the outer
layer to reason about belief, likelihood or certainty based on
potentially incomplete or contradictory evidence, building on
BelnapDunn logic as an inner logic of the underlying evidence. This
results in twolayered logics suitable for reasoning scenarios when
aggregated evidence yields a Belnapian probability measure or a belief
function on a De Morgan algebra.
(This talk is rooted in joint work with S. Frittella, D. Kozhemiachenko,
O. Majer and S. Nazari.)
 Nina Gierasimczuk (Technical University of Denmark, DK):
Learning and Dynamic Modal Logic
In my talk I will discuss the modallogical and topological perspective on learnability.
The first links between dynamic epistemic logic and computational learning theory was introduced in [6,7,8],
where it was shown that exact learning in finite time (also known as finite identification, see [10,11]) can be modelled in
dynamic epistemic logic, and that the elimination process of learning by erasing [9] can be seen as iterated upgrade of dynamic doxastic logic.
This bridge opened a way to study truthtracking properties of doxastic upgrade methods on positive, negative, and erroneous input [2,4].
Switching from relational to topological semantics for modal logic allowed characterising favourable conditions for learning in the limit in
terms of general topology [3] and culminated in proposing a Dynamic Logic for Learning Theory, which extends Subset Space Logics [5] with dynamic
observation modalities and a learning operator [1].
[1] Baltag, Gierasimczuk, Özgün, VargasSandoval, and Smets, A dynamic logic for learning theory, Journal of Logical and Algebraic Methods in Programming, vol. 109 (2019), pp. 100485.
[2] Baltag, Gierasimczuk, and Smets, Belief revision as a truthtracking process, Proceedings of TARK’11, ACM, New York, 2011, pp. 187190.
[3] Baltag, Gierasimczuk, and Smets, On the solvability of inductive problems: A study in epistemic topology, Proceedings of TARK’15, vol. 215, EPTCS, 2016, pp. 8198.
[4] Baltag, Gierasimczuk, and Smets, Truthtracking by belief revision, Studia Logica, vol. 107 (2019), no. 5, pp. 917947.
[5] Dabrowski, Moss, and Parikh, Topological reasoning and the logic of knowledge, Annals of Pure and Applied Logic, vol. 78 (1996), no. 1, pp. 73110.
[6] Gierasimczuk, Bridging learning theory and dynamic epistemic logic, Synthese, vol. 169 (2009), no. 2, pp. 371384.
[7] Gierasimczuk, Learning by erasing in dynamic epistemic logic, Proceedings of LATA’09, vol. 5457, LNCS, Springer, 2009, pp. 362373.
[8] Gierasimczuk, Knowing One’s Limits. Logical Analysis of Inductive Inference, PhD thesis, Universiteit van Amsterdam, The Netherlands, 2010.
[9] Lange, Wiehagen, and Zeugmann, Learning by erasing, ALT 1996: Algorithmic Learning Theory, vol. 1160, LNCS, Springer, 1996, pp. 228241.
[10] Lange and Zeugmann, Types of monotonic language learning and their characterization, Proceedings of COLT’92, ACM, New York, 1992, pp. 377390.
[11] Mukouchi, Characterization of finite identi cation, Proceedings AII’92, vol. 642, LNCS, Springer, 1992, pp. 260267.
 Elaine Pimentel (University College London, UK):
Proof theory, countermodels and optimal complexity for modal logics  This is a joint talk with Tiziano Dalmonte.
When referring to proof theory for modal logics, undoubtedly there are sequent calculi
for a number of modal logics exhibiting many good properties (such as
analyticity) which can be used in complexityoptimal decision
procedures. However, their construction often seems adhoc, they are
usually not modular, and they mostly lack philosophically relevant
properties such as separate left and right introduction rules for the
modalities. These problems are often connected to the fact that the
modal rules in such calculi usually introduce more than one connective
at a time.
One way of solving this problem is by considering extensions of the
sequent framework that are expressive enough for capturing these
modalities using separate left and right introduction rules.
In this talk we explore the connections between several sequent based calculi
for normal and nonnormal modal and deontic logics. By proposing local
versions to ordinary sequent rules we obtain analytic calculi for a
number of logics, including to our knowledge the first nested/hyper sequent
calculi for a large class of simply dependent multimodal logics,
and for many standard nonnormal modal logics. The resulting systems
are modular and have separate left and right introduction rules for the modalities.
While this granulation of the sequent rules introduces more choices for proof
search, we propose terminating proof search strategies in the calculi, shown optimal in
most of the cases. Finally, we show how to directly extract countermodels for failed proof
attempts and launch some ideas of applications to the Dynamic setting.
This is a joint work with Tiziano Dalmonte, Nicola Olivetti and Björn Lellmann.
 Fernando Velázquez Quesada (University of Bergen, NO):
(Arbitrary) partial communication
Dynamic epistemic logic (DEL) is the extension of epistemic logic that focuses on representing actions that transform the individual and collective knowledge/beliefs of a set of agents.
Its main feature is that actions are semantically represented as operations that modify the underlying semantic model. The paradigmatic DEL proposals (public and diverse forms of nonpublic announcements, belief revision)
study epistemic actions through which the agents receive information from an external source. Yet, the agents do not need to wait for some external entity: they can also share their individual information with one another.
This talk discusses some of such actions, focussing in particular on that of "partial communication": a set of agents sharing all their information about a particular topic.
The first part of the talk defines the model operation representing this action, discussing some of its basic properties, presenting an axiom system for its modality, and comparing it with a public announcement.
The second part of the talk introduces a further dynamic modality that quantifies over topics, a form of arbitrary partial communication.
Once again, the talk discusses the action's basic properties, its axiom system as well as its relationship with its public announcement counterpart, arbitrary public announcements.
This is joint work with Rustam Galimullin.
List of Accepted Papers (alphabetically, by first author)
A booklet with all accepted full papers can be found here.
List of Accepted Short Papers (alphabetically, by first author)
A booklet with all accepted short papers can be found here.
Important dates

May 3rd, 2022  May 18th, 2022 (Extended!): Abstract deadline

May 10th, 2022  May 25th, 2022 (Extended!): Full paper deadline

June 15th, 2022  July 2nd, 2022 (Extended!): Author notification
 July 15th, 2022: Final version deadline (booklet)
 TBA: Post proceedings deadline
 TBA: Special issue invitation
Submissions and publications
Authors are invited to submit original papers (unpublished and not submitted for publication elsewhere) up to 15 pages in LNCS style.
Papers will be published in a
Lecture Notes in Computer Science Volume, Springer.
Extended versions of selected contributions will be published in a special issue of the
Journal of Logical and Algebraic Methods in Programming, Elsevier.
Extended abstracts with preliminarily results and work in progress (25 pag) are also welcomed for short presentations.
Submissions should be handled with Easychair, following this link.
Topics
We invite submissions on the general field of Dynamic Logic, its variants and applications, including, but not restricted to:
 Dynamic logic, foundations and applications
 Logics with regular modalities
 Modal/temporal/epistemic logics
 Kleene and action algebras and their variants
 Quantum dynamic logic
 Coalgebraic modal/dynamic logics
 Graded and fuzzy dynamic logics
 Dynamic logics for cyberphysical systems
 Dynamic epistemic logic
 Complexity and decidability of variants of dynamic logics and temporal logics
 Model checking, model generation and theorem proving for dynamic logics
Venue and Registration
DaLí is now an online event and will be hosted on Zoom.
Registration is free. Please register using the following link:
DaLí registration.