A conference on the occasion of the 50th birthday of
Tullio Ceccherini-Silberstein
Rome, February 22-24, 2017


Invited Speakers

Alexander Bufetov (Moscow / Marseille)
Michel Coornaert (Strasbourg)
Rostislav Grigorchuk (College Station)
Vadim Kaimanovich (Ottawa)
Tatiana Nagnibeda (Geneva)
Klaus Schmidt (Vienna)
Stanislav Smirnov (Geneva)
Alain Valette (Neuchatel)


Alfredo Donno, Fabio Scarabotti, Filippo Tolli (Rome)
Daniele D'Angeli, Wolfgang Woess (Graz)


Dipartimento S.B.A.I. - Sapienza - Università di Roma
Via Antonio Scarpa, 14, 00161 Roma, Italia

How to get to the building E (RM004) where the meeting takes place (Aula Seminari): local map (pdf)

If you take the subway, the closest station is Policlinico (Line B). From Termini train station, take bus 310 and get off at viale Ippocrate. From Fiumicino and Ciampino Airport you can reach Stazione Termini by train or shuttle bus.


There is no registration fee.
To register, please send a mail with subject matter "Tullio" to
woess [at] tugraz [dot] at
and specify the intended day/time of arrival/departure


(IT = invited talk; T = talk; OA = opening address)
  1. Alexander Bufetov (Moscow / Marseille) IT: "Conditional measures of determinantal point processes and the Lyons-Peres conjecture"
  2. Michele D'Adderio (Bruxelles) T: "The sandpile model on complete bipartite graphs"
  3. Daniele D'Angeli (Graz) T: "Wreath product of matrices"
  4. Matteo Cavaleri (Rome) T: "The universal sofic action"
  5. Tullio Ceccherini-Silberstein (Benevento / Rome)
  6. Michel Coornaert (Strasbourg) IT: "Surjunctivity of algebraic dynamical systems"
  7. Alfredo Donno (Rome)
  8. Alessandro Figà-Talamanca (Rome) OA
  9. Francesca Fiorenzi (Paris-Orsay)
  10. Elizaveta Frenkel (Moscow) T: "Free-constructible groups"
  11. Agelos Georgakopoulos (Warwick) T: "On the expected size of a patriarchal mafia with Poisson distributed collaborations"
  12. Dina Ghinelli (Rome) OA
  13. Francesco de Giovanni (Napoli) T: "Groups of large cardinality"
  14. Thibault Godin (Paris)
  15. Rostislav Grigorchuk (College Station) IT: "An interesting  example  of  computation of  the spectrum of a certain group of intermediate  growth"
  16. Vadim Kaimanovich (Ottawa) IT: "L-amenable actions"
  17. Antonio Machì (Rome) OA
  18. Claudia Malvenuto (Rome)
  19. Elia Manara (Milano) T: "A class of unitary representations of surface groups"
  20. Alessandro Milanesi (Roma)
  21. Tatiana Nagnibeda (Geneva) IT: "Group actions, subshifts and spectra"
  22. Florin Radulescu (Rome) T: "Endomorphisms of spaces of virtual vectors fixed by a discrete group"
  23. Emanuele Rodaro (Milano) T: "On the undecidability of problems related to freeness and finiteness"
  24. Amnon Rosenmann (Graz) T: "Properties resulting from the arboresque structure of free groups and free group algebras"
  25. Sandra Saliani (Potenza)
  26. Maura Salvatori (Milano)
  27. Fabio Scarabotti (Rome)
  28. Klaus Schmidt (Vienna) IT: "Periodic and homoclinic points of algebraic Z^d-actions"
  29. Stanislav Smirnov (Geneva) IT: "A few things about the self avoiding walk in the plane"
  30. Filippo Tolli (Rome)
  31. Alain Valette (Neuchatel) IT: "Box spaces: bridging geometric and asymptotic group theory"
  32. Wolfgang Woess (Graz) T: "Isotropic random processes on ultrametric spaces"


A pdf file with arrival instructions, the program and the abstracts of the talks can be downloaded here.


Wednesday, 22 February

  9:20-  9:50 opening: Ghinelli, Figà-Talamanca, Machì
  9:50-10:40 Grigorchuk
10:40-11:10 Coffee break
11:10-12:00 Nagnibeda
12:10-12:40 D'Adderio

14:30-15:20 Bufetov
15:30-16:00 D'Angeli
16:00-16:30 Coffee break
16:30-17:20 Coornaert
17:30-18:00 de Giovanni

Thursday, 23 February

  9:20-  9:50 Rodaro
10:00-10:40 Georgakopulos
10:40-11:10 Coffee break
11:10-12:00 Valette
12:10-12:40 Radulescu

14:30-15:00 Frenkel
15:10-16:00 Schmidt
16:00-16:30 Coffee break
16:30-17:00 Cavaleri
17:10-18:00 Smirnov

Friday, 24 February

  9:20-  9:50 Rosenmann
10:00-10:30 Manara
10:30-11:00 Coffee break
11:00-11:50 Kaimanovich
12:00-12:30 Woess
12:30-12:40 concluding words


Participants are asked to take care of accomodation by themselves. We suggest the following two Hotels:
Globus Hotel
Hotel delle Province


Dipartimento S.B.A.I. - Sapienza Università di Roma

Last modified on February 23, 2017
Für den Inhalt verantwortlich: Prof. Wolfgang Woess, TU Graz, Steyrergasse 30, 8010 Graz, Austria