Rebecca Waldecker
Professor for Algebra

rebecca_waldecker Photo: Karsten Möbius (2018) Contact Phone +49 345 5524623 Fax +49 345 5527002 Email rebecca.waldecker[at]
Postal adress Prof. Dr. Rebecca Waldecker Martin Luther University Halle-Wittenberg Institute of Mathematics 06099 Halle (Saale)

  • Diese Seite auf Deutsch
  • Rebecca Waldecker - Professor for Algebra
    Currriculum vitae

    My full name is Rebecca Anne Hedwig Waldecker. I was born in Aachen in 1979 and I grew up in northern Germany.

    Academic positions
    • Since March 2015 Professor for Algebra at the Martin Luther University Halle-Wittenberg.
    • Oktober 2009 - Februar 2015 Junior professor for groups and geometries at the University of Halle (Germany).
    • May 2007 - September 2009 Research Fellow at the University of Birmingham,funded by the Leverhulme Trust, on a grant with Paul Flavell.
    • January - April 2007 Honorary Lecturer at the University of Birmingham, School of Mathematics.
    Education and qualification
    • Habilitation at the Martin Luther University Halle-Wittenberg (2014).
    • PhD at the Christian-Albrechts-Universität zu Kiel (2007).
    • 2003 - 2006 PhD student at the Christian-Albrechts-Universität zu Kiel.
    • Diplom (undergraduate degree) in Mathematics, Statistics und Econometrics at the Christian-Albrechts-University of Kiel (2003).
    Rebecca Waldecker - Professor for Algebra

    Most of my current research projects come from applications of group theory. This can be about using symmetry in order to improve algorithms or to solve problems in science outside of mathematics, about the structure of finite groups or specific applications of permutation group theory. I am fascinated by questions from other areas where symmetry plays a role or where a problem can be translated into a group theoretic problem and then solved.

    • Towards the Z*_3-Theorem, with Imke Toborg.  Submitted.
    • Finite simple permutation groups acting with fixity 4, with Barbara Baumeister, Paula Hähndel, Kay Magaard, Patrick Salfeld und Anika Streck. In preparation.
    • L9-free groups, with Clemens Tietze and Imke Toborg. In preparation.
    • Permutation group algorithms based on directed graphs, with Chris Jefferson, Markus Pfeiffer and Wilf Wilson. In revision.
    • The occurrence of finite simple permutation groups of fixity 3 as automorphism groups of Riemann surfaces, with Patrick Salfeld. In preparation.
    • Finite groups of fixity 2, revisited, with Anika Streck. In preparation.

    Publications since 2015:
    • Textbook Elementare Algebra und Zahlentheorie, with Gernot Stroth. Second edition of his 2012 book.
    • The occurrence of finite simple permutation groups of fixity 2 as automorphism groups of Riemann surfaces, with Patrick Salfeld, has appeared online in Journal of Algebra.
    • Online version.
    • The Sylow structure of transitive permutation groups acting with fixity 4, with Barbara Baumeister und Kay Magaard. Special issue in honor of Kay Magaard, Albanian J. Math. 12 (2018), 137-145. Available online.
    • New refiners for permutation groups search, with Chris Jefferson and Markus Pfeiffer. Journal of Symbolic Computation 92 (2019), 70-92. Online version.
    • Minimal and canonical images, with Chris Jefferson, Eliza Jonauskyte and Markus Pfeiffer. Journal of Algebra 521 (2019), 481-506. Online here.
    • Questions on orbital graphs, with Paula Hähndel. In: Davenport J., Kauers M., Labahn G., Urban J. (eds) Mathematical Software - ICMS 2018. Lecture Notes in Computer Science, vol 10931. Springer, Cham. Here is the online version.
    • Permutation groups where non-trivial elements have few fixed points, in "Finite Simple Groups: Thirty Years of the Atlas and Beyond", herausgegeben von M. Bhargava, R. M. Guralnick, G. Hiss, K. Lux and P. H. Tiep. Contemporary Mathematics 694, AMS (2017), 223-229.
    • Rempe-Gillen, Lasse and Waldecker, Rebecca, Primzahltests für Einsteiger, 2nd edition. Springer, 2015.
    • Magaard, Kay und Waldecker, Rebecca, Transitive permutation groups with trivial four point stabilizers, J. Group Theory 18 (2015), no. 5, 687-740.
    • Pölzing, Juliane and Waldecker, Rebecca, M9-free groups, J. Group Theory 18 (2015), 155-190.
    • Magaard, Kay and Waldecker, Rebecca, Transitive permutation groups where nontrivial elements have at most two fixed points, Journal of Pure and Applied Algebra 219, Issue 4 (2015), 729-759.

    Publications before 2015 can be found here.

    • DFG grant 2020/21 for a project extending the spectrum of search algorithms.
    • Funding from the VolkswagenStiftung (2018-2019) for a summer school on "Constructive Matrix Group Recognition in GAP", with Alice Niemeyer.
    • Grant for a summer school at the Institute Mittag-Leffler (Stockholm) with Cheryl Praeger and Donna Testerman.
    • Project funded by the VolkswagenStiftung (2018-2019) for "Exploring Graph Backtracking".
    • Cheryl Praeger Visiting Research Fellowship 2017 (stay at the UWA).
    • DFG grants 2013, 2014 and 2016.
    • Funding for conferences.
    • Mercator-Professorship for Chris Parker (2011) with Gernot Stroth.
    • 2007 Conference Grant from the London Mathematical Society.
    • 2003-2006 Grant from the Studienstiftung des deutschen Volkes for postgraduate students.
    • 2002 Grant from the DAAD for a short term visit in Paris.
    • 1998-2003 Grant from the Studienstiftung des deutschen Volkes for undergraduate students.

    Rebecca Waldecker - Professor for Algebra

    Here is a list of courses that I teach frequently:

    Linear Algebra, Algebra, Galois theory, Group theory, representation theory, coxeter groups and chamber systems, number theory, special topics in group theory.

    Many of them have accompanying workshops, audio files of the lectures, podcasts and, more recently, videos. There are also sporadic workshops on other topics, often from a more philosophical perspective or with advice for students.
    I am happy about suggestions for workshop topics or podcasts!

    Summary of teaching experience before 2010

    For my teaching page in German and more information, please go to my German webpage and then to "Lehre".
    Rebecca Waldecker - Professor for Algebra

    Students who are intersted in algebraic topics can work on projects with me for a qualification thesis (Bachelor, Master, PhD), and I also have PostDoc projects.

    At the Bachelor thesis level the topics can vary from number theory or aspects of graph theory to Galois theory or, of course, group theory, also with computational or historical aspects or related to representation theory. More advanced work with me (e.g. Master thesis) has to be in group theory and needs some background knowledge from advanced courses.

    More information and examples for topics of theses can be found on my German page at "Betreuung".
    Rebecca Waldecker - Professor for Algebra
    The young group theorists conference "Grüppchen"

    The "Grüppchen" is a conference for young group theorists that takes place once a year, alternatingly between Halle and Gießen. The talks are mostly in German. For more information please visit my German homepage and look at "Das Grüppchen".
    Rebecca Waldecker - Professor for Algebra

    Here are some activities, just email me in case of any questions!
    • Coaching of students and young researchers, mentoring (in networks and informally).
    • School visits and presentations, information at open days, support of mathematics teachers.
    • Workshops on mathematical topics and on topics related to coaching and teaching.
    • Audio files of all my lectures, podcasts, a blog on special questions.
    • Activities for students in their first year to help overcome transition problems from school to university.
    • Newsletter of the Maths Institute.
    • Liaison person for the German Academic Scholarship Foundation since 2012.
    • Vice president of the German Association of University Professors and Lecturers since 2016.
    • Head of the Maths Institute 2015-2019.
    • Active member of several faculty and university committees.
    • Local organiser of the Northern German Group Theory Colloquium and the Halle-Jena-Seminar in Algebra.
    • Co-organiser of the Young Group Theorists Conference ("Grüppchen") and the Summer School on Finite Groups and Related Geometrical Structures.
    Rebecca Waldecker - Professor for Algebra

    Talks since 2014

    In the year 2020 I mainly did some virtual talks or presentation videos, so far. Some examples: Algebra Seminar of the University of Birmingham, ICMS (Session with Bettina Eick) and a seminar talk for a wide audience at the University of Namibia.

    • "How we search for symmetry by breaking it", joint talk with Wilf Wilson at Forum Experiment! in Hannover, 27th November 2019.
    • "Isolated elements in finite groups" at the conference "Group Theory in Berlin" in Berlin, 20th September 2019.
    • "Groups acting with low fixity: status and plans" at the meeting "Groups and representations: A conference in memory of Kay Magaard" in Warwick (UK), 11th September 2019.
    • "Towards a Z*_p-Theorem" at the Workshop "groups and Geometries" in Banff (Kanada), 27th August 2019.
    • Spotlight lecture "One question, two perspectives, three projects" at the summer school "Modern theory of group actions and the special role of finite simple groups", Mittag-Leffler Institute (Stockholm), 6th June 2019.
    • Plenary talk "Kanonische Bilder" at a Computeralgebra conference in Kassel, 18th May 2019.
    • "The four fixed points project" at the Northern German Group Theory Colloquium in Braunschweig, 29th June 2018.
    • OSCAR-Workshop at the MPI Leipzig, 12th Dezember, "Orbital graphs".
    • Nikolaus-Konferenz in Aachen, 8th Dezember, "Orbital graphs".
    • Oberseminar Algebra at the RWTH Aachen, 7th Dezember 2017, "Unterwegs zum Z*_3-Satz".
    • Lecture Series for the Modern Mathematics International Summer School in Bremen, 7th - 9th July, "Permutation groups".
    • "Snowflakes, viruses and algorithms" Mathematics and Statistics Colloquium at the UWA (Perth), 16th March.
    • "Orbital graphs" at the Groups and Combinatorics Seminar, UWA (Perth), 10th March.
    • "Finding and using symmetry", Mathematics Seminar at the University of Dundee, 8th August.
    • Talk at Conference "Group Theory, Geometry and the Influence of Jacques Tits" in Karlsruhe, 27th May: "Towards a Z*_3-Theorem".
    • NBSAN-Meeting: "Applying permutation group theory" at the University of St Andrews, 18th March.
    • CIRCA-Seminar "Fixity and subgroup structure" at the University of St Andrews, 26th August.
    • Lecture Series for the Modern Mathematics International Summer School in Bremen, 4th - 9th July, on Coxeter chamber systems.
    • Inaugural lecture "Was sind und was können Gruppen?" at the Martin-Luther-Universität Halle-Wittenberg, 21th May.
    • Talk at the Workshop "Algorithms for Linear Groups" in Banff, 20the November: "Permutation groups where non-trivial elements have few fixed points".
    • Lecture Series for the Modern Mathematics International Summer School in Lyon, 22nd - 29th August, on the topics group theory and primality testing.
    • Talk at the Martin-Luther-Universität Halle-Wittenberg, 24th July, for the application to a professorship: "Permutation groups and Riemann Surfaces".
    • Mathematics Colloquium at the Martin-Luther-Universität Halle-Wittenberg, 3rd July: "Permutation groups working hard".
    Talks before 2014