Christian Elsholtz


  • 1997/99: Wissenschaftlicher Mitarbeiter, University of Stuttgart
  • 1999/2003 Wissenschaftlicher Assistent, Technical University of Clausthal
  • 2003-2006: Lecturer in Pure Mathematics at Royal Holloway, University of London.
  • 2006-2009: Senior Lecturer in Pure Mathematics at Royal Holloway, University of London.
  • 2009-2010: Reader in Mathematics, University of London.
  • (Tenure since 2006.)
  • Since 2010 Associate Professor at TU Graz, Austria.


  • Diplom (M.Sc.) in Mathematics, 1996, Technical University of Darmstadt.
  • Ph.D., 1998, Technical University of Darmstadt.
    Subject: Sums of k Unit Fractions.
    My Ph.D. ancestors

  • Habilitation/Privatdozent 2002, Technical University of Clausthal.
    Title: Combinatorial prime number theory- A study of the gap structure of the set of primes.
    I am occasionally asked: "what is Habilitation?"
    The Habilitation is a formal degree based on postdoctoral work, (and is considered to be more significant than a Ph.D.) In the German system it is the highest scientific qualification. It consists of a written Thesis, a talk on current research including an oral exam, and a lecture to demonstrate teaching skills. For each of the latter two talks I had to submit three distinct subjects (covering the whole range of mathematics) of which the faculty chose: The crossing number in graph theory and its applications, and Fair division of sandwiches and cakes.


    Fields of Interest:
  • Combinatorial, and analytic number theory, additive and multiplicative problems
  • Graph Theory, combinatorics and geometry (in particular extremal graph theory)
    my number theoretic interests in detail:

    my algebraic interests detail:
    my combinatorial interests in detail:

    Here is a link to a list of my scientific work.
    Teaching material.

    Research project ArithRand.

    My PhD student Gabriel Lipnik was awarded his PhD by the president of Austria, a very high honour.

    This is a link (2014) about jobs, which ranks the job of a mathematician highest (i.e. as "best" job), the rank of a University professor as second...

    Some old links below:

  • Royal Holloway, University of London
  • In 2010 Royal Holloway ranked worldwide 88th place in the Times Higher Education University ranking
  • What the German News magazine "Der Spiegel" wrote on studying at Royal Holloway (30.10.2009) The article starts with "It's hard to study in a more beautiful way: a Castle with opulent Campus, the studies are very British")
  • I used to organise the Pure Maths seminar at Royal Holloway for some years. Current Pure Maths seminars at RHUL.
    At Royal Holloway I used to be director of the two Master courses
    MSc in Mathematics of Cryptography & Communications and
    MSc in Mathematics for Applications
    At Royal Holloway I organised talks for schools, such as Exploring Mathematics
    Collection of useful links (books, journals, dictionaries etc).
    A two days workshop ArithRand 22, Graz, with Thomas Stoll.
    A two days workshop on the occasion of Prof. Tichy's 60th birthday (2017, organized with Peter Grabner)
    I organized ELAZ 2016 (September 5-9 2016), in Strobl.
    I organized a Number theory day 2003.
    I co-organised the Workshop analytische Zahlentheorie (3.-7. April 2000) Goslar (ELAZ 2000)