Celsius Lecture: Two and a Half Millennia of Irrationality in Mathematics
- Date: 13 February 2025, 09:00–12:00
- Location: Ångström Laboratory, Sonja Lyttkens
- Type: Lecture
- Lecturer: Francesco Calegari, University of Chicago
- Web page
- Organiser: Faculty of Science and Technology
- Contact person: Karin Thellenberg
- Phone: 018-4714947
The discovery of irrational numbers - especially the fact that √2 is not rational - is often attributed to the Pythagorean philosopher Hippasus. According to legend, this revelation so disturbed his fellow Pythagoreans that they drowned him in a lake. In this talk, we will explore the long (often unsuccessful) history of our attempts to understand irrationality, with the goal of explaining how mathematicians really think about these questions. Our journey will span from ancient Greece to the ancien régime, from 17th-century Basel to the present day.
Here you can read more about the lecture.
Each year the Faculty of Science and Technology arranges the Celsius-Linnaeus honorary lectures in memory of Anders Celsius and Carl von Linné. The selected Celsius- and Linnaeus-lecturers are at today's forefront within their field.
2025 Celsius lecturer is Francesco Calegari. Frank Calegari was born in Australia in 1975 where he attended the University of Melbourne. Frank was a graduate student of Ken Ribet at Berkeley. After a postdoctoral position at Harvard, Frank was a professor at Northwestern University until he moved to the University of Chicago in 2015 where he has been ever since. Frank was an American Institute of Mathematics five year fellow, a Sloan fellow, and was elected as a fellow of the American Mathematical Society in 2013. In 2022, Frank gave a plenary address at the (virtual) International Congress of Mathematicians.
After the lecture there will be a symposium with lectures given by Julia Brandes, Chalmers Tekniska Högskola and University of Gothenburg and Anders Karlsson, Uppsala university. The symposium ends with a panel discussion.
The 2025 Linnaeus Lecturer, Andrea Rinaldo, will give his lecture at Geocentrum starting 13.30.
Read more here about the Celsius-Linnaeus Lectures and see a more detailed program.