Yes, very sad news. I knew Thomas from the complete spreads project (which are a class of geometric morphism). In particular together (with Marta and Mamuka) we solved the problem of identifying what is complete about complete spreads. Ultimately, we needed fibrations in order to explain it - Thomas kept us on the straight and narrow. I loved talking with Thomas about mathematics. It was in his blood. I'll never forget the first time we met (nearly 30 years ago) in that pub somewhere in Utrecht: he came up to me and said: ``Hello, my name is Thomas Streicher'' with such force it nearly bowled me over. Now that is how to introduce yourself. So long Thomas, RIP. Jon ________________________________ From: Oosten, J. van (Jaap) <J.vanOosten@uu.nl> Sent: Friday, January 3, 2025 4:04 AM To: categories@mq.edu.au <categories@mq.edu.au> Cc: Oosten, J. van (Jaap) <J.vanOosten@uu.nl> Subject: Thomas Streicher * This email originates from a sender outside of CUNY. Verify the sender before replying or clicking on links and attachments. * I just received information that Thomas Streicher passed away yesterday. Thomas fell ill last September, when he could not attend Pino Rosolini's retirement party due to pneumonia; then it turned out he has metastases in the lungs from a pancreatic cancer. After several chemo treatments his situation suddenly worsened, and yesterday he died, peacefully, without pain. Thomas was 66 years old. In Thomas, we mourn a logician and category theorist of exceptional calibre. Let me just recall that in 2011, during an Oberwolfach meeting, Vladimir Voevodsky praised Thomas' work on type theory as a paradigm of precision. But I personally mourn a friend. A warm person with many interests. I wish strength to his wife Eva, and his family. Jaap van Oosten You're receiving this message because you're a member of the Categories mailing list group from Macquarie University. To take part in this conversation, reply all to this message. View group files<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=files&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Leave group<https://outlook.office365.com/owa/categories@mq.edu.au/groupsubscription.ashx?source=EscalatedMessage&action=leave&GuestId=6bf90c14-94d1-45b7-a0b5-9dd447734d27> | Learn more about Microsoft 365 Groups<https://aka.ms/o365g>