# Online: Seminar, Roberto Longo (University of Rome Tor Vergata), The Information in a Wave #### calendar\_today Date and Time **May 5, 2020** 10:00AM - 10:00AM EDT #### pin\_drop Location **Zoom** ![Roberto Longo](/sites/g/files/omnuum6611/files/styles/hwp_1_1__360x360_scale/public/mathpicture/files/roberto_longo.jpeg?itok=ZuGQLV1d) **Location:** Zoom [https://harvard.zoom.us/j/779283357 ](https://harvard.zoom.us/j/779283357%C2%A0) **Time:** Tuesday, May 5, 2020, 10:00 AM (Eastern US), 16:00 (Central Europe), 22:00 (China) **Title:** The Information in a Wave **Abstract:** Suppose that some information is transmitted by an undulatory signal. In Classical Field Theory, the stress-energy tensor provides the energy-momentum density of the wave packet at any time. But, how to measure the information, or entropy, carried by the wavepacket in a certain region at given time? Surprisingly, one can answer the above (entirely classical) question by means of Operator Algebras and Quantum Field Theory. In fact, in second quantisation a wave packet gives rise to a sector of the Klein-Gordon Quantum Field Theory on the Rindler spacetime W. The associated vacuum noncommutative entropy of the global von Neumann algebras of W is the entropy of the wave packet in the wedge region W of the Minkowski spacetime. One can then read this result in first quantisation via a notion of entropy of a vectorof a Hilbert space with respect to a real linear subspace. I give a path to the above results by an overview of some of basic results in Operator Algebras and Quantum Field Theory and of the relation with the Quantum Null Energy Inequality. **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 +1 253 215 8782 +1 301 715 8592 +1 346 248 7799 +41 43 210 70 42 +41 43 210 71 08 +41 22 591 00 05 +41 22 591 01 56 +41 31 528 09 88 +31 20 794 6520 +31 20 794 7345 +31 20 241 0288 +31 20 794 0854 +31 20 794 6519 +65 3165 1065 +65 3158 7288 +33 1 7095 0350 +33 7 5678 4048 +33 1 7037 2246 +33 1 7037 9729 +33 1 7095 0103 +49 30 5679 5800 +49 695 050 2596 +49 69 7104 9922 +45 32 72 80 11 +45 89 88 37 88 +45 32 70 12 06 +45 32 71 31 57 +45 32 72 80 10 400 669 9381 China Toll-free 400 616 8835 China Toll-free 0 800 561 252 Switzerland Toll-free 0 800 002 622 Switzerland Toll-free 0 800 220 0040 Netherlands Toll-free 0 800 022 1954 Netherlands Toll-free 800 852 6054 Singapore Toll-free 800 101 3814 Singapore Toll-free 0 805 082 588 France Toll-free 0 800 940 415 France Toll-free 0 800 1800 150 Germany Toll-free 0 800 000 6954 Germany Toll-free 80 82 02 88 Denmark Toll-free 80 71 12 51 Denmark 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 ](/sites/g/files/omnuum6611/files/mathpicture/files/longo_seminar_may_5_2020.pdf) --- Share on:- [ Facebook ](#) - [ Twitter ](#) - [ Linkedin ](#) Save: [ Add to calendar calendar\_today ](https://mathpicture.fas.harvard.edu/node/1502022/event-feed.ics) Copy link link