VCLA International Student Awards 2024 – Award Ceremony
| DATE: | Monday, June 30, 2025 |
| TIME: | 17:30 – 18:30 |
| VENUE: | Favoritenstraße 9-11, Helmut Veith Lecture Hall |
The VCLA held an award ceremony for the VCLA International Student Awards 2024 on June 30, 2025 as part of DEON, the 17th International Conference on Deontic Logic and Normative Systems.
VCLA Co-Chair Agata Ciabattoni welcomed the guests and introduced the VCLA International Student Awards. Subsequently, the Co-Chairs of the Awards, Shqiponja Ahmetaj and Anela Lolic, said a few words about the speakers and their award-winning theses. Nathaniel Collins, who received the Outstanding Undergraduate Research Award, presented his thesis “Count-Free Weisfeiler–Leman and Group Isomorphism,” and Tikhon Pshenitsyn told the audience about his work on “Hypergraph Lambek Calculus,” for which he received the Outstanding Master Thesis Award. Each presentation had a duration of twenty minutes, followed by five minutes of Q&A. We congratulate the winners on their outstanding achievements, and look forward to announcing the winners of the current edition in the upcoming months!
Shqiponja Ahmetaj, Anela Lolic, Nathaniel Collins, Tikhon Pshenitsyn, Agata Ciabattoni
| 17:30 | Welcome address by VCLA Co-Chair Agata Ciabattoni |
| Introduction to the VCLA International Student Awards by the Chairs of the Awards | |
| 17:40 | Outstanding Undergraduate Research Award |
| Nathaniel Collins: “Count-Free Weisfeiler–Leman and Group Isomorphism” | |
| 18:05 | Outstanding Master Thesis Award |
| Tikhon Pshenitsyn: “Hypergraph Lambek Calculus” | |
| 18:30 | Reception |
Speakers & Abstracts
Nathaniel Collins (University of Colorado Boulder)
“Count-Free Weisfeiler–Leman and Group Isomorphism”
We investigate the power of the counting and count-free variants of the Weisfeiler–Leman (WL) Version I algorithm for groups (Brachter & Schweitzer, LICS 2020).
• We study the counting and count-free versions of the Weisfeiler–Leman algorithm when applied to so-called CFI groups, which arise from CFI graphs (Cai, Fürer, & Immerman, Combinatorica, 1992) via Mekler’s construction (J. Symb. Log., 1981). We use O(log log n) rounds of WL Version I, improving upon the work of Brachter & Schweitzer, who used O(log n) rounds of WL Version II. As a consequence, we obtain improvements in both the parallel and descriptive complexities of identifying these groups.
• We further improve the parallel complexity using count-free WL Version I, bounded non-determinism, and limited counting. In particular, we obtain a β1MAC0(FOLL) isomorphism test for CFI groups.
Tikhon Pshenitsyn (formerly Lomonosov Moscow State University, now Russian Academy of Sciences)
“Hypergraph Lambek Calculus”
