The borders of Outer space
53 mins 15 secs,
773.01 MB,
MPEG-4 Video
640x360,
29.97 fps,
44100 Hz,
1.93 Mbits/sec
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About this item
| Description: |
Vogtmann, K
Friday 23rd June 2017 - 14:30 to 15:30 |
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| Created: | 2017-07-19 16:26 |
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| Collection: | Non-Abelian Fundamental Groups in Arithmetic Geometry |
| Publisher: | Isaac Newton Institute |
| Copyright: | Vogtmann, K |
| Language: | eng (English) |
| Distribution: |
World
(downloadable)
|
| Explicit content: | No |
| Aspect Ratio: | 16:9 |
| Screencast: | No |
| Bumper: | UCS Default |
| Trailer: | UCS Default |
| Abstract: | Outer space is an analog for the group Out(F_n) of the symmetric space associated to an algebraic group. Motivated by work of Borel and Serre, Bestvina and Feighn defined a bordification of Outer space; this is an enlargement of outer space which is highly-connected at infinity and on which the action of Out(F_n) extends, with compact quotient. We realize this bordification as a deformation retract of Outer space instead of an extension. We use this to give a simpler connectivity proof, and to give a description of the boundary nicely analogous to that of the Borel-Serre boundary of a symmetric space. This is joint work with Kai-Uwe Bux and Peter Smillie. |
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| MPEG-4 Video * | 640x360 | 1.93 Mbits/sec | 773.01 MB | View | Download | |
| WebM | 640x360 | 497.22 kbits/sec | 193.99 MB | View | Download | |
| iPod Video | 480x270 | 522.31 kbits/sec | 203.71 MB | View | Download | |
| MP3 | 44100 Hz | 249.78 kbits/sec | 97.51 MB | Listen | Download | |
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