BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260205T220633EST-2261KMPvdh@132.216.98.100 DTSTAMP:20260206T030633Z DESCRIPTION:CRM-Montreal-Quebec Analysis Seminar\n\nTitle: A Schwarz-Jack L emma and its Application\n\nAbstract: The Schwarz lemma is one of the corn erstones of geometric function theory. Jack’s lemma is another influential result in the field\, though it is somewhat less well known. In this work \, we introduce a new result\, the Schwarz–Jack lemma\, which is strongly inspired by both of these classical lemmas. The main requirement of the le mma\, known as the Jack condition\, can be satisfied in several different ways\, some of which we discuss. This result emerged from our study of the celebrated Crouzeix conjecture\, which asserts that the numerical range o f any $n \times n$ matrix is a 2-spectral set. While the conjecture has be en established for the case $n = 2$\, it remains open for $n \ge 3$. Exist ing proofs for $n = 2$ are highly technical and rely heavily on explicit f ormulas for conformal mappings from an ellipse onto the unit disk. The bro ader aim of our work is twofold: first\, to clarify the intrinsic properti es of the conformal mappings involved\, thereby reducing reliance on expli cit formulas\; and second\, to provide a conceptual framework that may all ow for further generalizations. The Schwarz–Jack lemma plays a central rol e in achieving these goals.\n\nJoint work with A. Moucha\, R. O’Loughlin\, O. Roth\, and T. Ransford.\n\nVenue: hybrid seminar at ULaval\, Pavillon  Alexandre-Vachon\, room 2820\n DTSTART:20260213T193000Z DTEND:20260213T203000Z SUMMARY:Javad Mashreghi (Université Laval) URL:/biology/channels/event/javad-mashreghi-universite -laval-371121 END:VEVENT END:VCALENDAR