CAUTION: The Sender of this email is not from within Dalhousie. Dear all, We are pleased to announce that the Proof Theory Virtual Seminar series will restart this autumn on Wednesday 6 October with a talk by Professor Jeremy Avigad. A list of this season's speakers can be found below, as well as other useful information. The Proof Theory Virtual Seminar is an online seminar series that presents talks by leading researchers from all areas of proof theory. It was launched in October 2020 and typically has talks on the first and third Wednesdays of the month, alternating between morning (9am UTC) and afternoon (5pm UTC) to facilitate international participation. 6 October, 17:00 UTC. Jeremy Avigad (Carnegie Mellon University). Title: The conservativity of weak K??nig's lemma (a proof from the book). 20 October, 09:00 UTC. Fedor Pakhomov (Ghent University and Steklov Mathematical Institute) Title: Fast growing hierarchies, ordinal collapsing, and ???????-CA???. 3 November, 17:00 UTC. Wilfried Sieg (Carnegie Mellon University). Title: Proofs as objects. 17 November, 09:00 UTC. Alexis Saurin (Centre National de la Recherche Scientifique) Title: (TBA) 1 December. (No seminar due to Proof Society Winter School and Workshop, 29 November - 4 December). 15 December, 09:00 UTC. Alessio Guglielmi (University of Bath). Title: (TBA) Joining details, abstracts and other information can be found on the seminar website: https://www.proofsociety.org/proof-theory-seminar/ If you would like to receive reminders, you can sign up to our email list by joining the following google group (no google account required): https://groups.google.com/forum/#!forum/proof-theory-seminar/join Best wishes, Lev Beklemishev, Yong Cheng, Anupam Das, Anton Freund, Thomas Powell, Sam Sanders, Monika Seisenberger, Andrei Sipos, Henry Towsner [For admin and other information see: http://www.mta.ca/~cat-dist/ ]