Summary SYM meeting October 2016

AGENDA
1) New people, announcements
2) Organize events
3) DNRF visits on November 21 at 9-12
4) arXiv preprint presentations from August and September (see below for September preprints)

ad 1)
- Niek de Kleijn and Kristian Knudsen Olesen have succesfully defended their theses
- Massimiliano Ungheretti will defend his thesis October 14
- Felix Boes is visiting to give seminar talk
- Simon Hausmann has been born (son of Markus Hausmann and Angela Hausmann nŽe Klamt)

ad 2)
- The department deadline for applying for masterclass funding from the PhD School is October 21.  See emails from Mikael R¿rdam for more details.
- TopTop in block 2 will this year be 1-week sessions on 9 topics.  If you would like to teach 1 week, please let Jesper Grodal know.

ad 3)
The Danish National Research Foundation (DNRF) funds SYM.  Unless you're teaching in group B in block 2, please participate in the meeting.
- There will be a presentation on the state of the center.
- There will be 2-3 scientific talks.
- We will end with a nice lunch.
- Before lunch, DNRF would like to speak to *all* postdocs.
- Detailed program will be send out.

ad 4)
See below for September arXiv preprints.  5-minute blackboard preprint presentations by:
- Jesper Grodal (arXiv:1608.00499)
- Rune Haugseng (arXiv:1608.01290)
- Kristian Knudsen Olesen (arXiv:1609.05086)

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September arXiv preprints
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arXiv:1609.07635
Title: Amenable groups of finite cohomological dimension and the zero divisor conjecture
Authors: Dieter Degrijse
Categories: math.GR Group Theory (math.FA Functional Analysis)
Comments: 12 pages
Report number: CPH-SYM-DNRF92
Abstract: We prove that every amenable group of cohomological dimension two whose integral group ring is a domain is solvable and investigate certain homological finiteness properties of groups that satisfy the analytic zero divisor conjecture and act on an acyclic CW-complex with amenable stabilisers.

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arXiv:1609.05086
Title: Non-inner amenability of the Thompson groups T and V
Authors: Uffe Haagerup, Kristian Knudsen Olesen
Categories: math.OA Operator Algebras (math.GR Group Theory)
Comments: 13 pages
Report number: CPH-SYM-DNRF92
Abstract: In this paper we prove that the Thompson groups $T$ and $V$ are not inner amenable. In particular, their group von Neumann algebras do not have property $\Gamma$. Moreover, we prove that if the reduced group $C^\ast$-algebra of $T$ is simple, then the Thompson group $F$ is non-amenable. Furthermore, we give a few new equivalent characterizations of amenability of $F$.