This Festschrift is dedicated to Christel Baier in recognition of her contributions to the field of theoretical computer science, particularly in formal methods, temporal logics, model checking, and probabilistic systems.

After earning her doctorate from the University of Mannheim, Christel Baier held research and professorial positions in Mannheim and Bonn. Since 2006 she has been a full professor of Algebraic and Logical Foundations of Computer Science at Technische Universität Dresden, where she currently serves as the Dean of the Faculty of Computer Science. In 2011, she was elected to the Academia Europaea. She was the Editor-in-Chief of Acta Informatica from 2015 to 2022, and received an honorary doctorate from RWTH Aachen University in 2022. Among her many notable research achievements, Christel Baier has shaped the foundations and practical applications of system verification. She pioneered probabilistic model checking, advanced techniques for model checking of continuous-time Markov chains, and coauthored the standard textbook Principles of Model Checking. Beyond her research contributions, she is widely respected within the scientific community. Her service has included invited talks, membership in key steering and program committees, and organizing scientific events.

Christel Baier has mentored and guided many students and fellow scientists. They appreciate her way of approaching every task with remarkable persistence, focus, and diligence. Many of these collaborators were pleased to contribute to this volume and to celebrate joint work and successes.

Contributions from leading scientists Contributions explain important research and implementation successes Honors an influential researcher, mentor, and community leader

Inhalt

The Optimal Strategy to Meet the Deadline: Ask Christel.- Nondeterminism in Interactive Markov Chains, with Application to the Erlangen Mainframe.- Decisiveness for countable MDPs and insights for NPLCSs and POMDPs.- Polytopal Stochastic Games.- Algorithmic Applications of Schanuel's Conjecture.- Stop gambling! It just takes too long.- Probabilistic Model Checking: Applications and Trends.- Probabilistic Counterexamples Through the Ages.- PCTL Satisfiability for Infinite Binary Trees.- CTL Verification and Synthesis using Existential Horn Clauses.- Featured Message Sequence Graphs.- A Note on Runtime Verification of Concurrent Systems.- Embedding Monitoring of First-order Temporal Logic in a Programming Language.- Causality Monitoring for MIMOS.- Owicki/Gries Proof Method: Parameterized Soundness and Completeness.- On the Verification of Quantum Programs.- Efficient Join Order for Constraint Automata through LLM-Generated Heuristics.- What-If Scenarios for the BedreFlyt Digital Twin.- Running.Christel: a stochastic hybrid case-study optimizing battery pack usage.- Termination in Extended Probabilistic Threshold Automata.