BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20250711T223810EDT-3141drlRwr@132.216.98.100 DTSTAMP:20250712T023810Z DESCRIPTION:Title: Classical and emerging ideas in sparse high-dimensional approximation.\n\nAbstract: Approximating functions of many variables from limited samples is a key task in modern computational mathematics and dat a science. This task is made intrinsically difficult by the so-called curs e of dimensionality\, a term introduced by R.E. Bellman in the 1970s that refers to computational challenges arising in high dimensions. The objecti ve of this seminar is to introduce classical and emerging mathematical ide as in high-dimensional approximation.\n \n We will illustrate the rudiments of sparse polynomial approximation theory\, motivating our study with appl ications to parametric differential equations. Specifically\, we will pres ent methods for computing sparse polynomial approximations of holomorphic functions of many variables from limited Monte Carlo samples\, focusing on techniques based on least squares and compressed sensing and showing unde r what circumstances they are provably able to alleviate the curse of dime nsionality. Time permitting\, we will also discuss how these ideas come in to play in current research areas such as deep learning approximation theo ry and spectral methods for high-dimensional PDEs. This seminar is mainly based on the book 'Sparse Polynomial Approximation of High-Dimensional Fun ctions'\, co-authored by the speaker with B. Adcock and C.G. Webster\, and published for SIAM in 2022 (http://www.sparse-hd-book.com).\n\n \n\nSemin ar location: 4336-4384 Pavillon Aisenstadt\, UdeM\n DTSTART:20221018T180000Z DTEND:20221018T190000Z SUMMARY:Simone Brugiapaglia (Concordia University) URL:/mathstat/channels/event/simone-brugiapaglia-conco rdia-university-342827 END:VEVENT END:VCALENDAR