Rothschild Lecture: Classification of von Neumann algebras

59 mins 31 secs,  213.74 MB,  WebM  640x360,  29.97 fps,  44100 Hz,  490.33 kbits/sec
Share this media item:
Embed this media item:


About this item
Image inherited from collection
Description: Vaes, S (KU Leuven)
Monday 12th June 2017 - 16:00 to 17:00
 
Created: 2017-06-30 12:39
Collection: Operator algebras: subfactors and their applications
Publisher: Isaac Newton Institute
Copyright: Vaes, S
Language: eng (English)
Distribution: World     (downloadable)
Explicit content: No
Aspect Ratio: 16:9
Screencast: No
Bumper: UCS Default
Trailer: UCS Default
 
Abstract: The theme of this talk is the dichotomy between amenability and non-amenability. Because the group of motions of the three-dimensional Euclidean space is non-amenable (as a group with the discrete topology), we have the Banach-Tarski paradox. In dimension two, the group of motions is amenable and there is therefore no paradoxical decomposition of the disk. This dichotomy is most apparent in the theory of von Neumann algebras: the amenable ones are completely classified by the work of Connes and Haagerup, while the non-amenable ones give rise to amazing rigidity theorems, especially within Sorin Popa's deformation/rigidity theory. I will illustrate the gap between amenability and non-amenability for von Neumann algebras associated with countable groups, with locally compact groups, and with group actions on probability spaces.
Available Formats
Format Quality Bitrate Size
MPEG-4 Video 640x360    1.94 Mbits/sec 866.59 MB View Download
WebM * 640x360    490.33 kbits/sec 213.74 MB View Download
iPod Video 480x270    522.3 kbits/sec 227.62 MB View Download
MP3 44100 Hz 249.75 kbits/sec 108.96 MB Listen Download
Auto (Allows browser to choose a format it supports)