Christopher Voll, PhD (cantab)
Welcome to this page.
Contact
Prof. Dr. Christopher Voll
Fakultät für Mathematik
Universität Bielefeld
Postfach 100131
D-33501 Bielefeld
Germany
Telephone: 0049-521-1065025
Telephone (secretary Ms N. Nopto): 0049-521-1065021
Email: surname at math dot uni minus bielefeld dot de
|
I also maintain a research affiliation
with Mathematics at the
University of Southampton, UK.
Elsevier boycott
I joined a number of researchers - more than 11.600 as of 16 May 2012
- in boycotting Elsevier, the academic publisher;
see The Cost of Knowledge
for background.
Kolloquium
I coordinate the
Mathematisches
Kolloquium at
Bielefeld.
CV
Click here for a 3-page CV.
Research
My research interests are centred around
asymptotic group theory, in particular arithmetic and analytic
properties of zeta functions associated to infinite groups and
rings. These are Dirichlet generating functions encoding arithmetic
data about groups and rings, such as the numbers of finite index
subobjects or finite-dimensional irreducible representations. The
study of these zeta functions may be seen as a non-commutative
analogue to the theory of the Dedekind zeta function of a number
field, enumerating finite index ideals in the number field's ring of
integers. This young subject area lies on the crossroads of infinite
group and ring theory, algebraic geometry and combinatorics. I have
written "A newcomer's guide to zeta functions of groups and rings",
see here.
I welcome enquiries about possible PhD projects from suitably
qualified candidates. I am also happy to consider sponsoring postdoc
applications, e.g. under the Marie Curie Actions.
Papers (submitted for publication)
- Arithmetic groups, base change, and representation growth, with
N. Avni, B. Klopsch and
U. Onn, arxiv
- Enumerating classes and characters of p-groups, with
E. A. O'Brien, arxiv
- Representation zeta functions of nilpotent groups and
generating functions for Weyl groups of type B, with
A. Stasinski,
arxiv
Book chapters
- A newcomer's guide to zeta functions of groups and rings, in
B. Klopsch, N. Nikolov, C. Voll, Lectures on profinite topics in
group theory, editor D. Segal, London Mathematical Society Student
Texts 77, Cambridge University Press, 2011, see CUP,
also arxiv
- Zeta functions of groups - singular pfaffians, in Essays in
Geometric Group Theory, editor N. S. N. Sastry, Ramanujan
Mathematical Society Lecture Notes Series, No. 9, 2009, see
also arxiv
Papers (published or accepted for publication)
- Representation zeta functions of compact p-adic
analytic groups and arithmetic groups, with N. Avni, B. Klopsch and
U. Onn,
arxiv, to appear in
Duke Math. J.
- Representation zeta functions of some compact p-adic
analytic groups, with N. Avni, B. Klopsch and U. Onn,
arxiv, in Contemporary
Mathematics 566 (2012)
- Functional equations for zeta functions of groups and rings,
Ann. Math. 172 (2010),
1181--1218, pdf, arxiv
- On representation zeta functions of groups and a conjecture
of Larsen-Lubotzky, with N. Avni, B. Klopsch and U. Onn,
C. R. Math. Acad. Sci. Paris, Ser. I 348 (2010), 363--367, arxiv
- Enumerating finite class-2-nilpotent groups on 2 generators,
C. R. Math. Acad. Sci. Paris, Ser. I 347 (2009), 1347-1350 arxiv
- Zeta function of 3-dimensional p-adic Lie algebras, with
B. Klopsch, Math. Z. 263, No. 1 (2009),
195--210, pdf, arxiv
- Igusa-type functions associated to finite formed spaces and
their functional equations, with B. Klopsch,
Trans. Amer. Math. Soc. 361 (2009),
4405--4436, pdf, arxiv
- Counting subgroups in a family of nilpotent semidirect
products, Bull. London Math. Soc., No. 38 (2006),
743--752, pdf, arxiv
- Normal subgroup growth in free class-2-nilpotent groups,
Math. Ann. 332, No. 1 (2005),
67--79, pdf, arxiv
- Functional equations for local normal zeta functions of
nilpotent groups, with an appendix by A. Beauville,
Geom. Func. Anal. (GAFA) 15 (2005),
274--295, pdf, arxiv
- Zeta functions of groups and enumeration in Bruhat-Tits
buildings, Amer. J. Math. 126 (2004),
1005--1032, pdf, arxiv
Grants
- EPSRC Small
Grant EP/H044779/1 (with B. Klopsch, PI) to collaborate
with Uri Onn,
Ben-Gurion University of the Negev, Beersheva, Israel.
- EPSRC Overseas
Travel Grant EP/H044779/1 to
visit Eamonn
O'Brien, Auckland, NZ.
- EPSRC Small
Grant EP/G055408/1 (with B. Klopsch) for
workshop Representations
and Asymptotic Group Theory, 6-7 April 2009 in
Southampton.
- EPSRC First
Grant EP/F044194/1 Zeta functions of groups and rings and Igusa's
local zeta function", 04/2009-03/2012.
- Nuffield
Foundation Newly Appointed Lecturers Grant,
09/2006-04/2009.
- Royal Society Outgoing
Short Visits grant to visit E. O'Brien (Auckland, NZ) and B. Martin
(Christchurch, NZ), 07/2008.
- Fonds National
Suisse Individual Short Visit to
visit Laurent
Bartholdi (then EPFL, Switzerland), 03-04/2006.
- Max-Planck-Institut
für Mathematik, Bonn, Weiterbildungsstipendium,
10/2005-03/2006.
- Deutsche
Forschungsgemeinschaft Forschungsstipendium, Mathematisches
Institut der Heinrich-Heine-Universität Düsseldorf,
10/2004-09/2005.
- EPSRC
Postdoctoral Fellowship in
Mathematics GR/R93827/01
"Bruhat - Tits buildings and functional equations of zeta functions
of nilpotent groups", Mathematical Institute, University of Oxford,
10/2002-09/2004.
Research group
I am involved in the South
England Profinite Groups Meetings, a Joint Research Group
supported by an LMS Scheme 3
grant. For information on the next meeting click here.
Meetings organised
Postdocs
PhD students
Teaching (in German)
Sommersemester 2012
Wintersemester 2011/12
- GHR-Vertiefungsvorlesung Gruppen und Symmetrie
- Vorlesung Kommutative Algebra
Last updated: 22 May 2012