This is a special collaboration between Diversity Committee and Tea - FaculTea Day! Don’t have an advisor? Don’t know which research group to join? The FaculTea Day will be a chance for you to come talk with faculty and get to know what they do. Already have an advisor or research group? Come anyway! You can help provide information to your potential future academic siblings.
The first examples of groups in a textbook are often as words in generators, subject to some easy rules. This seems nice and natural, but gets quickly abandoned once the groups involved become more complicated. A similar disappointment happens when introducing group extensions: Examples in textbooks never go beyond easy cases such as cyclic groups or split extensions. But this is not intended to whine about textbooks. Instead I want to show how a systematic approach to normal form words (namely confluent rewriting systems) can be used to describe group extension (and explicitly compute 2-cohomology), resulting in practically useful (and implemented!) algorithms.