Christoph Spiegel

Postdoctoral reasearcher working
on Combinatorics, Optimization
and Learning

AIS2T @ Zuse Institute
Room 3036 • 14195 Berlin
spiegel@zib.de
Office hours
Wednesdays at the Zuse
Institute by e-mail appointment
Publications

proceedings

  1. Kiem, A., Pokutta, S., and Spiegel, C.
    Categorification of Flag Algebras.
    Proceedings of Discrete Mathematics Days, 2024.
    [URL]
  2. Kiem, A., Pokutta, S., and Spiegel, C.
    The 4-color Ramsey Multiplicity of Triangles.
    Proceedings of Discrete Mathematics Days, 2024.
    [URL] [arXiv] [code]
  3. Mundinger, K., Pokutta, S., Spiegel, C., and Zimmer, M.
    Extending the Continuum of Six-Colorings.
    Proceedings of Discrete Mathematics Days, 2024.
    [URL] [arXiv]
  4. Zimmer, M., Spiegel, C., and Pokutta, S.
    Sparse Model Soups: A Recipe for Improved Pruning Via Model Averaging.
    Proceedings of International Conference on Learning Representations, 2024.
    [URL] [arXiv]
  5. Parczyk, O., Pokutta, S., Spiegel, C., and Szabó, T.
    Fully Computer-assisted Proofs in Extremal Combinatorics.
    Proceedings of AAAI Conference on Artificial Intelligence, 2023.
    [DOI] [URL] [arXiv] [code]
  6. Rué, J. J., and Spiegel, C.
    The Rado Multiplicity Problem in Vector Spaces Over Finite Fields.
    Proceedings of European Conference on Combinatorics, 2023.
    [DOI] [URL] [arXiv] [code]
  7. Zimmer, M., Spiegel, C., and Pokutta, S.
    How I Learned to Stop Worrying and Love Retraining.
    Proceedings of International Conference on Learning Representations, 2023.
    [URL] [arXiv] [code]
  8. Parczyk, O., Pokutta, S., Spiegel, C., and Szabó, T.
    New Ramsey Multiplicity Bounds and Search Heuristics.
    Proceedings of Discrete Mathematics Days, 2022.
    [arXiv] [code]
  9. Rué, J. J., and Spiegel, C.
    On a Problem of Sárközy and Sós for Multivariate Linear Forms.
    Proceedings of Discrete Mathematics Days, 2018.
    [URL] [arXiv]
  10. Kusch, C., Rué, J. J., Spiegel, C., and Szabó, T.
    Random Strategies Are Nearly Optimal for Generalized Van Der Waerden Games.
    Proceedings of European Conference on Combinatorics, 2017.
    [URL] [arXiv]

journal

  1. Mundinger, K., Pokutta, S., Spiegel, C., and Zimmer, M.
    Extending the Continuum of Six-Colorings.
    Geombinatorics Quarterly, XXXIV, 2024.
    [URL] [arXiv]
  2. Parczyk, O., Pokutta, S., Spiegel, C., and Szabó, T.
    New Ramsey Multiplicity Bounds and Search Heuristics.
    Foundations of Computational Mathematics, 2024.
    [arXiv] [code]
  3. Kamčev, N., and Spiegel, C.
    Another Note on Intervals in the Hales-Jewett Theorem.
    Electronic Journal of Combinatorics, 29(1), 2022.
    [DOI] [URL] [arXiv]
  4. Cao-Labora, G., Rué, J. J., and Spiegel, C.
    An Erdős-Fuchs Theorem for Ordered Representation Functions.
    Ramanujan Journal, 56, 183–2091, 2021-10.
    [DOI] [URL] [arXiv]
  5. Fabian, D., Rué, J. J., and Spiegel, C.
    On Strong Infinite Sidon and Bₕ Sets and Random Sets of Integers.
    Journal of Combinatorial Theory, Series A, 182, 2021-08.
    [DOI] [URL] [arXiv]
  6. Corsten, J., Mond, A., Pokrovskiy, A., Spiegel, C., and Szabó, T.
    On the Odd Cycle Game and Connected Rules.
    European Journal of Combinatorics, 89, 2020-10.
    [DOI] [URL] [arXiv]
  7. Candela, P., Serra, O., and Spiegel, C.
    A Step Beyond Freĭman’s Theorem for Set Addition Modulo a Prime.
    Journal De Théorie Des Nombres De Bordeaux, 32(1), 275–289, 2020.
    [DOI] [URL] [arXiv]
  8. Rué, J. J., and Spiegel, C.
    On a Problem of Sárközy and Sós for Multivariate Linear Forms.
    Revista Matemática Iberoamericana, 36(7), 2107–2119, 2020.
    [DOI] [URL] [arXiv]
  9. Kusch, C., Rué, J. J., Spiegel, C., and Szabó, T.
    On the Optimality of the Uniform Random Strategy.
    Random Structures & Algorithms, 55(2), 371–401, 2019-09.
    [DOI] [URL] [arXiv]
  10. Freĭman, G. A., Serra, O., and Spiegel, C.
    Additive Volume of Sets Contained in Few Arithmetic Progressions.
    INTEGERS, 19, 2019.
    [URL] [arXiv]
  11. Rué, J. J., Spiegel, C., and Zumalacárregui, A.
    Threshold Functions and Poisson Convergence for Systems of Equations in Random Sets.
    Mathematische Zeitschrift, 288, 333–360, 2018.
    [DOI] [URL] [arXiv]
  12. Spiegel, C.
    A Note on Sparse Supersaturation and Extremal Results for Linear Homogeneous Systems.
    Electronic Journal of Combinatorics, 24(3), 2017.
    [DOI] [URL] [arXiv]

preprint

  1. Zimmer, M., Andoni, M., Spiegel, C., and Pokutta, S.
    PERP: Rethinking the Prune-Retrain Paradigm in the Era of LLMs..
    [arXiv] [code]
  2. Zimmer, M., Spiegel, C., and Pokutta, S.
    Compression-aware Training of Neural Networks Using Frank-Wolfe..
    [arXiv]
  3. Combettes, C., Spiegel, C., and Pokutta, S.
    Projection-free Adaptive Gradients for Large-scale Optimization..
    [arXiv] [summary] [code]
  4. Pokutta, S., Spiegel, C., and Zimmer, M.
    Deep Neural Network Training with Frank-Wolfe..
    [arXiv] [summary] [code]
  5. Salia, N., Spiegel, C., Tompkins, C., and Zamora, O.
    Independent Chains in Acyclic Posets..
    [arXiv]
Talks

conference and workshop talks

September 2024   CO@Work, Berlin [PDF]

July 2024   13th DMD Conference, Alcalá de Henares [PDF]

October 2023   BMS RTA 8 - Practical Course, Berlin [PDF]

August 2023   12th EuroComb Conference, Prague [PDF]

August 2023   ICIAM 2023 Minisymposium: Advances in Optimization I, Tokyo [PDF]

August 2023   5th DOxML Conference, Tokyo [PDF]

June 2023   FoCM 2023 Workshop I.3 Workshop, Paris [PDF]

May 2023   15th CANT Conference, New York [PDF]

March 2023   Optimization and ML Workshop, Waischenfeld [PDF]

February 2023   37th AAAI Conference, Washington, DC [PDF]

January 2023   combinatorial optimization workshop, Aussois [PDF]

December 2022   Recent Advances in Optimization Workshop, Toronto [PDF]

September 2022   6th RIKEN-MODAL Workshop, Tokyo and Fukuoka [PDF]

July 2022   12th DMD Conference, Santander [PDF]

June 2019   Postgraduate Combinatorial Conference, Oxford [PDF]

June 2019   GAPCOMB Workshop, Campelles [PDF]

June 2018   11th DMD Conference, Sevilla [PDF]

May 2018   10th CANT Conference, New York [PDF]

March 2018   GRAPHS at IMPA, Rio de Janeiro [PDF]

September 2017   The Music of Numbers Conference, Madrid [PDF]

June 2017   Interactions with Combinatorics [PDF]

March 2017   FUB-TAU workshop [PDF]


seminar talks

February 2023   LIMDA Seminar, Barcelona

April 2022   LIMDA Seminar, Barcelona

November 2019   Research Seminar Combinatorics, Berlin

November 2019   Research Seminar Large Networks and Random Graphs, Ilmenau

May 2019   Seminar and PhD Seminar on Combinatorics, Games and Optimisation, London

May 2019   Combinatorial Theory Seminar, Oxford

February 2019   Extremal Set Theory Seminar, Budapest

December 2018   Research Seminar Combinatorics, Berlin

December 2017   Research Seminar Combinatorics, Berlin

October 2017   LIMDA Seminar, Barcelona

May 2017   LIMDA Seminar, Barcelona

March 2016   LIMDA Seminar, Barcelona

February 2016   Research Seminar Combinatorics, Berlin

January 2016   Research Seminar Combinatorics, Berlin

December 2015   "What is ...?" seminar

October 2015   Research Seminar Combinatorics, Berlin

Teaching

Winter 2024   Lecturer for Formal Proof Verification at FUB

Summer 2024   Lecturer for Discrete Optimization (ADM II) at TUB

Winter 2023   Lecturer for Introduction to Linear and Combinatorial Optimization (ADM I) at TUB

Summer 2023   Lecturer for Analysis I und Lineare Algebra für Ingenieurwissenschaften at TUB

Autumn 2018   Assistant for Discrete Mathematics and Optimization at UPF

Autumn 2017   Assistant for Discrete Mathematics and Optimization at UPF

Winter 2013   Tutor for Analysis I (Lehramt) at FUB

Summer 2012   Tutor for Analysis II (Lehramt) at FUB

Summer 2011   Tutor for Analysis I (Lehramt) at FUB

Education
 June 2020  Ph.D. in Applied Mathematics at Universitat Politècnica de Catalunya   [PDF]

March 2015  Master of Science at Freie Universität Berlin

I wrote my master thesis on Approximating Primitive Integrals and Aircraft Performance (09/2014 - 03/2015) in the area of Graph Theory and Optimization under the supervision of Prof. Dr. Ralf Borndörfer. The research was part of the Flight Trajectory Optimization on Airway Networks project at the Zuse-Institute Berlin (ZIB). The main industry partner of this project is Lufthansa Systems Frankfurt. Furthermore it is part of the joint project E-Motion - Energieeffiziente Mobilität which is funded by the German Ministry of Education and Research (BMBF).During the course of my research I was employed as a student research assistant at the ZIB (05/2014 - 03/2015).

September 2012  Bachelor of Science at Freie Universität Berlin

I wrote my bachelor thesis on Numerical Pricing of Financial Derivatives (06/2012 - 09/2012) under the supervision of Prof. Dr. Carsten Hartmann.

Juni 2009  Abitur at Canisius-Kolleg Berlin

Fun Stuff

You can find some of my photography on instagram. I also like designing the occasional conference poster: