# Online: Seminar, Xiao-Gang Wen (MIT), Symmetry as a Shadow of Topological Order #### calendar\_today Date and Time **December 8, 2020** 10:00AM - 10:00AM EST #### pin\_drop Location **Zoom** ![Xiao-Gang Wen](/sites/g/files/omnuum6611/files/styles/hwp_1_1__960x960_scale/public/mathpicture/files/wen.png?itok=A35w9o09) **Location:** Zoom **Time:** Tuesday, December 8, 2020, 10:00 AM (Eastern US), 15:00 (UK/Eire), 16:00 (Central Europe), 23:00 (China) **Title:** Symmetry as a Shadow of Topological Order **Abstract:** In this talk, I will present a new way to look at symmetry. We show that symmetry can be viewed as non-invertible gravitational anomaly, and a non-invertible gravitational anomaly is classified by topological order in one higher dimension. This leads to a holographic view of symmetry: symmetry is a shadow of topological order in one higher dimension. This point of view allows us to see the duality (i.e. the equivalence) between symmetries that looks very different. It also gives rise to a more general symmetry--algebraic higher symmetry, which is beyond higher group description. **Additional Ways to Join** Join by telephone (use any number to dial in) +1 929 436 2866 +1 312 626 6799 +1 669 900 6833 400 669 9381 China Toll-free International numbers available: [https://harvar](https://harvard.zoom.us/u/aclg6kOggb)[d.zoom.us/u/aclg6kOggb](https://harvard.zoom.us/u/aclg6kOggb) One tap mobile: +19294362866,,779283357# US (New York) Join by SIP conference room system Meeting ID: 779 283 357 <779283357@zoomcrc.com> **Attachments** --- Attachments- [ picture\_as\_pdf Flyer.pdf ](/sites/g/files/omnuum6611/files/mathpicture/files/wen_december_8_2020_seminar.pdf) --- Share on:- [ Facebook ](#) - [ Twitter ](#) - [ Linkedin ](#) Save: [ Add to calendar calendar\_today ](https://mathpicture.fas.harvard.edu/node/1544818/event-feed.ics) Copy link link