BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//91���� Calendar - ECPv6.15.20//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-WR-CALNAME:91���� Calendar
X-ORIGINAL-URL:/calendar
X-WR-CALDESC:Events for 91���� Calendar
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20250309T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20251102T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20260308T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20261101T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20270314T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20271107T060000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20260415T150000
DTEND;TZID=America/New_York:20260415T160000
DTSTAMP:20260519T123704
CREATED:20260403T170808Z
LAST-MODIFIED:20260409T132251Z
UID:10007953-1776265200-1776268800@umaine.edu
SUMMARY:Mathematics Colloquium — Vector vs. Scalar Sup Norms
DESCRIPTION:MAT Colloquium\nWednesday\, April 15\, 2026\nHill Auditorium\, Barrows Hall\nRefreshments at 3:00pm\, Talk 3:15-4:05pm \nSpeaker: Jack Buttcane\, 91���� \nAbstract: \nRotations in three dimensions depend on three angles\, which we call the Euler angles. A function of the Euler angles can be expressed in terms of Wigner-D matrices\, which are representations of the rotation group SO(3). These matrix functions are strongly tied to quantum mechanics where they measure the probability of a state transition under a rotation\, but as a number theorist\, I am interested in their connection to automorphic forms: Suppose we have a vector-valued function of the 3×3 invertible matrices that transforms by a Wigner-D matrix under rotations. Then an interesting quantity to study is the “sup norm” sup_A ||f(A)||\, i.e. the maximum value of the length of the vector f(A) over 3×3 invertible matrices A. \nWe can also think of the function f as a vector of scalar-valued functions f=(f_{-d}\,…f_d) and for each entry f_j in the vector\, we can consider sup_A |f_j(A)|. The question I want to consider is\, to what extent does the ratio of these two sup norms depend exclusively on the Wigner-D matrix\, independent of the particular function f? As an undergraduate summer research project Andrii Obertas did some computations on this project and I’ll report on the outcome of those\, as well.
URL:/calendar/event/mathematics-colloquium/
LOCATION:Barrows Hall\, 91����\, Orono\, ME\, 04469\, United States
CATEGORIES:Lectures & Seminars
ORGANIZER;CN="Department of Mathematics & Statistics":MAILTO:mathstats@maine.edu
GEO:44.897732;-68.6687076
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=Barrows Hall 91���� Orono ME 04469 United States;X-APPLE-RADIUS=500;X-TITLE=91����:geo:-68.6687076,44.897732
END:VEVENT
END:VCALENDAR