Hi, I am Pascal.
In 2020 I received my BSc at Saarland University.
I continued my studies at Saarland University and obtained my MSc in 2022.
I am now a PhD student in a Dual PhD arrangement between Australian National University (under Assoc. Prof. Dr. Pascal Bercher)
and Saarland University (under Prof. Dr. Jörg Hoffmann).
I have two additional co-supervisors with whom I work very closely: Assoc. Prof. Dr. Álvaro Torralba and Assoc. Prof. Dr. Daniel Fišer from Aalborg University.
My research investigates how planners can exploit knowledge representations beyond the propositional representation that planners traditionally rely on. Specifically:
I develop heuristic search methods that remain effective even when planning tasks become too large to be represented in a propositional (ground) representation. This requires to access the description of a planning task in more efficient ways. This connects techniques for evaluating queries in database systems and rewriting Answer Set Programs.
I use linear programming techniques for planning. I started by improving linear program encodings used to derive potential heuristics. I now also look at using linear program solvers directly for (restricted forms of) planning and using user-provided linear constraints to make planning easier.
I analyze how different knowledge representations affect the computational complexity of finding a plan. Similar to my work on heuristic search, I have focused on the shift in complexity when considering propositional (ground) and first-order (lifted) encodings in classical and hierarchical planning. More recently, I have begun studying fragments of numerical planning.
P. Lauer,
Y. Zhang,
P. Haslum,
and
P. Bercher,
I Always Told My Mom That Order Is Overrated: Unordered HTN Planning is in PSPACE and Models Problems Beyond STRIPS, Proceedings of the 36th International Conference on Automated Planning and Scheduling (ICAPS'26), 2026.
P. Lauer,
and
D. Fišer,
Potential Heuristics: Weakening Consistency Constraints, Proceedings of the 35th International Conference on Automated Planning and Scheduling (ICAPS'25), 2025.
(Paper, Slides)
P. Lauer,
Á. Torralba,
D. Höller,
and
J. Hoffmann,
Continuing the Quest for Polynomial Time Heuristics in PDDL Input Size: Tractable Cases for Lifted hAdd, Proceedings of the 35th International Conference on Automated Planning and Scheduling (ICAPS'25), 2025.
(Paper, Appendix, Code, Slides)
P. Lauer,
S. Lin,
and
P. Bercher,
Tight Bounds for Lifted HTN Plan Verification and Bounded Plan Existence, Proceedings of the 35th International Conference on Automated Planning and Scheduling (ICAPS'25), 2025.
(Paper, Slides)
N. Karimi Bavandpour,
P. Lauer,
S. Lin,
and
P. Bercher,
Repairing Planning Domains Based on Lifted Test Plans, Proceedings of the 28th European Conference on Artificial Intelligence (ECAI'25), 2025.
(Paper)
P. Lauer,
Á. Torralba,
D. Fišer,
D. Höller,
J. Wichlacz,
and
J. Hoffmann,
Polynomial-Time in PDDL Input Size: Making the Delete Relaxation Feasible for Lifted Planning, Proceedings of the 30th International Joint Conference on Artificial Intelligence (IJCAI'21), 2021.
(Paper, Talk, Code)
Workshop Papers:
P. Lauer,
Y. Zhang,
P. Haslum,
and
P. Bercher,
PSPACE Planning With Expressivity Beyond STRIPS: Plan Constraints via Unordered HTNs, ILPs, Numerical Goals, and More, Proceedings of the 8th Workshop on Hierarchical Planning (HPLAN) at ICAPS'25, 2025.
(Paper, Poster)
P. Lauer,
Arguments in Favor of Allowing a Modeler to Constrain Action Repetitions, Proceedings of the Workshop on Knowledge Engineering for Planning and Scheduling (KEPS) at ICAPS'25, 2025.
(Paper, Slides)
R. Stern,
L. Lamanna,
A. Mordoch,
Y. Benyamin,
P. Lauer,
B. Juba,
G. Behnke,
C. Muise,
P. Bercher,
M. Vallati,
K. Xi,
O. Wattad,
and
O. Eliyahu,
Evaluating Planning Model Learning Algorithms, Proceedings of the Workshop on Knowledge Engineering for Planning and Scheduling (KEPS) at ICAPS'25, 2025.
P. Lauer,
Á. Torralba,
D. Höller,
and
J. Hoffmann,
A Lifted Backward Computation of hAdd, Proceedings of the 16th Workshop on Heuristic Search for Domain-Independent Planning (HSDIP) at ICAPS'24, 2024.
(Paper, Technical Report, Slides)
This paper is the workshop version of Lauer et al. in ICAPS 2025. Please refer to the conference version instead.
P. Lauer,
Á. Torralba,
D. Fišer,
D. Höller,
J. Wichlacz,
and
J. Hoffmann,
Polynomial-Time in PDDL Input Size: Making the Delete Relaxation Feasible for Lifted Planning, Proceedings of the 13th Workshop on Heuristic Search for Domain-Independent Planning (HSDIP) at ICAPS'21, 2021.
This paper is the workshop version of Lauer et al. in IJCAI 2021. Please refer to the conference version instead.
P. Lauer,
and
M. Fickert,
Beating LM-cut with LM-cut: Quick Cutting and Practical Tie Breaking for the Precondition Choice Function, Proceedings of the 12th Workshop on Heuristic Search for Domain-Independent Planning (HSDIP) at ICAPS'20, 2020.
(Paper, Talk)
Teaching:
[1st Sem '26] COMP3620/COMP6320 Artificial Intelligence (Tutor)
[1st Sem '26] COMP3630/COMP6363 Theory of Computation (Tutor)
The roles listed until 2025 were all teaching positions were at Saarland University. The roles starting from 2026 are at ANU.
At Saarland University, a teaching assistant prepares course materials and manages administrative and organizational tasks, while a separate lecturer is responsible for delivering the lectures. This is similar to a course convener at ANU.
At both Saarland University and ANU, tutors deliver the tutorials.
The supervising tutor sits between teaching assistant and tutor. This position takes on some responsibilities of the teaching assistant to support the coordination and organization of large tutor groups.
Academic services:
Reviewing:
I was a reviewer for the following journal(s):
Journal of Artificial Intelligence Research (JAIR)
(Journal Website)
Jonas Krück, MSc. Thesis, Title: Learning Heuristics for Hard to Ground PDDL Planning Tasks and Planning with Object Creation,
started October 2025 (ongoing),
Saarland University
Shuran Zhang, Honours Thesis, Title: Let Grounding Do the Heavy Lifting: Lifted Heuristics by Task Compilation,
started February 2025 (ongoing),
Australian National University
Sven Tangermann, MSc. Thesis, Title: Exploiting Symmetries in Lifted Heuristic Search,
submitted September 2025,
Saarland University
Ninos Oshana, BSc. Thesis, Title: Design, Implementation and Evaluation of Benchmarks in Lifted Planning,
submitted February 2024,
Saarland University
Jonas Krück, BSc. Thesis, Title: A Dynamic Approach to Lifted Successor Generation in Classical Planning,
submitted January 2024,
Saarland University
Other Activities:
2023-2021
: Organizer of
5 Tutor Didactics Seminars
(Prog2 2021, SE Lab 2021, Prog2 2022, Prog2/CySec 2 2023, SE Lab 2023)
2021-2020
: Organizer of
the Programming 2 Preparatory Course
(2020🔒, 2021🔒)
2019
: Founder and Organizer of
the Programming 2 Preparatory Course
(2019🔒)
