BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250718T034912EDT-1576BEZ0z8@132.216.98.100 DTSTAMP:20250718T074912Z DESCRIPTION:CRM-ISM Probability Seminar\n\nTitle: Number of saddles of the pure spherical p-spin model\n\nAbstract:\n\nThe pure spherical p-spin mode l is a Gaussian random polynomial H of degree p on an N-dimensional sphere \, with N large. The sphere is the state space of a physical system with m any degrees of freedom\, and the random function H is an energy landscape. \n\nUsing the Kac-Rice formula\, Auffinger\, Ben Arous and Cerny computed the average number of critical points of H with a given index\, and with e nergy below a given value. This average is exponentially large in N for p > 2\; the rate of growth\, called the complexity\, is a function of the in dex chosen and of the energy cutoff. The complexity describes the topology of H: below an energy threshold marking the bottom of the landscape\, all critical points are local minima or saddles with an index not diverging i n N\, and the complexity reveals a nested structure in these finite-index saddles.\n\nSubag’s remarkable 2017 paper used a second moment approach to show the total number of critical points concentrates around its mean. At the bottom of the landscape\, the average number of critical points is do minated by minima at the exponential scale\, demonstrating that typical be havior of the minima reflects their average behavior. We show the number o f critical points of any finite\, positive index concentrates around its m ean. This is a step towards understanding dynamics in the landscape\, thou ght to be related to protein folding and training neural nets. Joint work with Antonio Auffinger at Northwestern.\n\nLink: https://mcgill.zoom.us/j/ 87596694672?pwd=VG5WZjllUFdQVWxjN29rV2RMZDFlUT09\n\nMeeting ID: 875 9669 4 672\n\nPasscode: problab\n\n \n DTSTART:20210224T180000Z DTEND:20210224T190000Z SUMMARY:Julian Gold (Northwestern) URL:/mathstat/channels/event/julian-gold-northwestern- 327894 END:VEVENT END:VCALENDAR