BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//University of California\, Berkeley//UCB Events Calendar//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VTIMEZONE
TZID:America/Los_Angeles
BEGIN:STANDARD
TZOFFSETFROM:-0700
TZOFFSETTO:-0800
DTSTART:19701029T020000
RRULE:FREQ=YEARLY;BYMONTH=11;BYDAY=1SU
END:STANDARD
BEGIN:DAYLIGHT
DTSTART:19700402T020000
TZOFFSETFROM:-0800
TZOFFSETTO:-0700
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=2SU
END:DAYLIGHT
END:VTIMEZONE
BEGIN:VEVENT
DTSTAMP:20190410T100014Z
DTSTART;TZID=America/Los_Angeles:20190415T161000
DTEND;TZID=America/Los_Angeles:20190415T170000
TRANSP:OPAQUE
SUMMARY:Analysis and PDE Seminar: Global existence of small amplitude solutions for a model quadratic quasilinear wave-Klein-Gordon system in 2D
UID:125198-ucb-events-calendar@berkeley.edu
ORGANIZER;CN="UC Berkeley Calendar Network":
LOCATION:740 Evans Hall
DESCRIPTION:Annalaura Stingo\, UC Davis\n\nIn this talk we discuss the problem of global existence of solutions to a coupled wave-Klein-Gordon system in space dimension two when initial data are small\, smooth and mildly decaying at infinity. Several physical models related to general relativity have shown the importance of studying such systems but very few results are known at present in low space dimension\, where linear solutions slowly decay in time.\n\nWe study here a model quadratic quasilinear two-dimensional system\, in which the nonlinearity writes in terms of “null forms”\, and prove global existence by propagating a-priori energy estimates and optimal uniform estimates on the solution. In proving such estimates one has to deal with several issues such as the quasilinear nature of the problem\, the very low decay in time of quadratic nonlinearities\, the fact that initial data are not compactly supported…\n\nWe will show how to obtain energy estimates by using systematically quasilinear normal forms\, in their para-differential version. Uniform estimates will instead be recovered by deducing a new coupled system of a transport equation and an ordinary differential equation from the starting PDE system by means of a semiclassical microlocal analysis of the problem.
URL:http://events.berkeley.edu/index.php/calendar/sn/pubaff.html?event_ID=125198&view=preview
SEQUENCE:0
CLASS:PUBLIC
CREATED:20190410T100014Z
LAST-MODIFIED:20190410T100014Z
X-MICROSOFT-CDO-BUSYSTATUS:BUSY
X-MICROSOFT-CDO-INSTTYPE:0
X-MICROSOFT-CDO-IMPORTANCE:1
X-MICROSOFT-CDO-OWNERAPPTID:-1
END:VEVENT
END:VCALENDAR