RESEARCH PROFILE:
The core of my research programme is centered around logic and the use of its concepts and methods to model the laws and dynamics of different notions of information, knowledge and belief. I focus in particular on multi-agent systems that involve on the one hand quantum information flow and on the other hand the knowledge transfer (by classical communication) between agents. Hence I'm active in two very different research directions: A) quantum logic and information and B) logic, AI and epistemology. The latter direction is currently developing into the direction of logics to reason about social interaction, allowing us to build bridges between logic, AI and the social sciences, behavioral psychology as well as network theory.
Potential applications of my work on quantum logic can be found in the fields of security of communication and Quantum Computation. In my past VIDI research project (funded by NWO), my team developed the logical tools to provide a full specification and formal verification of several agent-based quantum protocols for secure communication. Our most recent work in this direction concerns models of complex situations where different types of informational dynamics (classical and quantum) are combined. We See my VIDI-project on Reasoning about Quantum Interaction. All work in this direction builds further on joint work with Alexandru Baltag, in which we have reformatted traditional quantum logic into a dynamic logical framework. Have a look at our publications on this topic: we provide a new setting and link (traditional) quantum logic to the needs of quantum computation and quantum information theory.
Research on logic and epistemology was carried out in the ERC LogiCIC project on The Logical Structure of Correlated Information Change. In this project, a team of researchers developed a unified logical setting to handle various types of correlated information change in a multi-agent context. This research has built on insights, concepts and methods from various fields including Dynamic Epistemic Logic, (Dynamic) Quantum Logic, Belief Revision theory, Topology, Truth Approximation theory and Formal Learning Theory. A summary of the project description is available here. The core of this work builds further on my joint work on belief revision and belief update which provides qualitative models (Kripke style) for (conditional) belief revision and update. This line of work is currently being developed further into the direction of logics for social networks.
My research interests cover: Logic (in particular non-classical logics, including non-monotonic logics, belief revision, modal and temporal logic, quantum logic); Multi-agent Systems in AI; Formal Epistemology; Social Epistemology; Knowledge Representation in AI; Philosophy of Quantum Physics, Quantum Information and Computation, Rationality and the role of "belief" in solution concepts in Games, the connection between logics for belief revision and Formal Learning Theory.
RESEARCH HIGHLIGHTS
On logic and quantum mechanics:
- Design of a new dynamic quantum logic, including a completeness result to show that all statements provable in the Hilbert space formalism for single quantum systems, are also provable in our relational-logic setting and vice versa [read more].
- Design of a new dynamic quantum logical formalism to reason about compound quantum systems in a setting that can be used to verify the correctness of quantum program-constructs [read more].
- Design of a probabilistic quantum logical system, used to express the formal correctness of several quantum protocols, including Quantum Leader Election, the Deutsch-Josza algorithm and a Quantum Search Algorithm in Quantum Information Theory [read more].
- Construction of a general proof method to show the decidability of probabilistic quantum logical systems [read more].
- Using insights from Epistemic Logic to provide a new information-logical characterization of the properties of "separability" and "quantum entanglement" in Quantum Systems [read more].
- Design of a first unified logical setting that encodes both classical information and quantum information [read more].
- A new philosophical analysis of the Frauchiger-Renner (FR) paradox [read more].
On logic, belief revision, learning and social networks:
- Design of a detailed qualitative theory of dynamic interactive belief revision, fully incorporating the work on Dynamic Epistemic Logic to model complex classical multi-agent learning scenarios as well as the AGM theory to model single-agent belief revision [read more].
- Design of an original semantic setting for belief dynamics that combines our qualitative work on dynamic interactive belief revision with the Bayesian approach in its extended Popper-Renyi (de Finetti) format (using Popper functions) [read more].
- Using Dynamic Epistemic Logic to analyze the backward induction paradox in Game Theory, providing a formalization of a new notion of dynamic rationality [read more].
- New analysis of the learning power of several belief revision methods, linking our work on belief revision directly to the core of formal learning theory [read more].
- Providing a new logical analysis of the decision processes of individuals that lead to the social herding phenomenon known as informational cascades [read more].
- In our latest line of work we provide a new topological semantics for evidence, evidence-based justifications, belief, and knowledge. [read more]
- Providing a new logical analysis of opinion diffusion in Social Networks, analyzing further the creation of social networks and the formation of echo-chambers and polarization in society from a logic-based perspective [read more].