• From June 2022 on I am Visiting Researcher at the Department of Electrical and Electronic Engineering at Imperial College London.
• Since September 2021 I am a research associate in Prof. Dr. Dr. h.c. Peter Maaß's working group at University of Bremen.
• During Summer Semester 2021 (01.04.2021 - 30.09.2021) I was interim professor at the Center for Industrial Mathematics at University of Bremen.
• From March 2020 to December 2020 I was Visiting Researcher in Dr. Ayush Bhandari's working group at Imperial College London.
• From October 2014 to September 2021 I was a research assistant/associate in Prof. Dr. Armin Iske's working group at University of Hamburg.

• Approximation theory
• Inverse problems (esp. computerized tomography)
• Machine learning (esp. for inverse problems)
• Signal processing and image analyse

• Modulo Radon Transform based Tomography (ModTomo)
  Funded by Deutsche Forschungsgemeinschaft (DFG)
  Period: 10/2024 - 09/2025
  Principal Investigator
• Hybrid Parameter Identification with Invertible Networks (KIWi)
  Funded by Bundesministerium für Bildung und Forschung (BMBF)
  Period: 11/2022 - 10/2025
  Principal Investigator

Dissertation

• Matthias Beckmann
  Error Estimates and Convergence Rates for Filtered Back Projection Reconstructions.
  Universität Hamburg, 2018.

Preprints

• Matthias Beckmann, Robert Beinert and Jonas Bresch
  Normalized Radon Cumulative Distribution Transforms for Invariance and Robustness in Optimal Transport Based Image Classification.
  arXiv: 2506.08761.
• Matthias Beckmann and Jürgen Jeschke
  Orthogonal Matching Pursuit based Reconstruction for Modulo Hysteresis Operators.
  Accepted at International Conference on Sampling Theory and Applications (SampTA).
  arXiv: 2504.05895.

Peer-reviewed Journal Articles

• Matthias Beckmann and Judith Nickel
  Optimized Filter Functions for Filtered Back Projection Reconstructions.
  Inverse Problems and Imaging 19(5), 2025, 903-939.
  DOI: 10.3934/ipi.2025003.
• Matthias Beckmann and Nick Heilenkötter
  Equivariant Neural Networks for Indirect Measurements.
  SIAM Journal on Mathematics of Data Science 6(3), 2024, 579-601.
  DOI: 10.1137/23M1582862.
• Matthias Beckmann, Ayush Bhandari and Meira Iske
  Fourier-Domain Inversion for the Modulo Radon Transform.
  IEEE Transactions on Computational Imaging 10, 2024, 653-665.
  DOI: 10.1109/TCI.2024.3388871.
• Matthias Beckmann, Ayush Bhandari and Felix Krahmer
  The Modulo Radon Transform: Theory, Algorithms and Applications.
  SIAM Journal on Imaging Sciences 15(2), 2022, 455-490.
  DOI: 10.1137/21M1424615.
• Matthias Beckmann, Peter Maass and Judith Nickel
  Error Analysis for Filtered Back Projection Reconstructions in Besov Spaces.
  Inverse Problems 37(1), 2021, 014002.
  DOI: 10.1088/1361-6420/aba5ee.
• Matthias Beckmann and Armin Iske
  Saturation Rates of Filtered Back Projection Approximations.
  Calcolo 57(1), 2020, 12.
  DOI: 10.1007/s10092-020-00360-y.
• Matthias Beckmann and Armin Iske
  Error Estimates and Convergence Rates for Filtered Back Projection.
  Mathematics of Computation 88(316), 2019, 801-835.
  DOI: 10.1090/mcom/3343.

Peer-reviewed Proceedings

• Matthias Beckmann and Carla Dittert
  On an Analytical Inversion Formula for the Modulo Radon Transform.
  International Conference on Scale Space and Variational Methods in Computer Vision (SSVM), 2025, 56-69.
  DOI: 10.1007/978-3-031-92366-1_5.
• Matthias Beckmann, Robert Beinert and Jonas Bresch
  Max-Normalized Radon Cumulative Distribution Transform for Limited Data Classification.
  International Conference on Scale Space and Variational Methods in Computer Vision (SSVM), 2025, 241-254.
  DOI: 10.1007/978-3-031-92366-1_19.
• Dominik Hauser, Matthias Beckmann, Günther Koliander and H. Siegfried Stiehl
  On Image Processing and Pattern Recognition for Thermograms of Watermarks in Manuscripts - A First Proof-of-Concept.
  International Conference on Document Analysis and Recognition (ICDAR), 2024, 91-107.
  DOI: 10.1007/978-3-031-70543-4_6.
• Matthias Beckmann and Ayush Bhandari
  MR. TOMP: Inversion of the Modulo Radon Transform (MRT) via Orthogonal Matching Pursuit (OMP).
  IEEE International Conference on Image Processing (ICIP), 2022, 3748-3752.
  DOI: 10.1109/ICIP46576.2022.9897428.
• Matthias Beckmann, Felix Krahmer and Ayush Bhandari
  HDR Tomography via Modulo Radon Transform.
  IEEE International Conference on Image Processing (ICIP), 2020, 3025-3029.
  DOI: 10.1109/ICIP40778.2020.9190878.
• Ayush Bhandari, Matthias Beckmann and Felix Krahmer
  The Modulo Radon Transform and its Inversion.
  European Signal Processing Conference (EUSIPCO), 2020, 770-774.
  DOI: 10.23919/Eusipco47968.2020.9287586.
• Matthias Beckmann and Armin Iske
  Convergence Rates for Hölder-Windows in Filtered Back Projection.
  IEEE International Conference on Sampling Theory and Applications (SampTA), 2019.
  DOI: 10.1109/SampTA45681.2019.9030855.
• Matthias Beckmann and Armin Iske
  Sobolev Error Estimates for Filtered Back Projection Reconstructions.
  IEEE International Conference on Sampling Theory and Applications (SampTA), 2017, 251-255.
  DOI: 10.1109/SAMPTA.2017.8024439.
• Matthias Beckmann and Armin Iske
  Error Estimates for Filtered Back Projection.
  IEEE International Conference on Sampling Theory and Applications (SampTA), 2015, 553-557.
  DOI: 10.1109/SAMPTA.2015.7148952.

Other Proceedings

• Matthias Beckmann and Armin Iske
  On the Error Behaviour of the Filtered Back Projection.
  Proc. Appl. Math. Mech. (PAMM) 16(1), 2016, 833-834.
  DOI: 10.1002/pamm.201610405.

Technical Reports

• Matthias Beckmann and Armin Iske
  Approximation of Bivariate Functions from Fractional Sobolev Spaces by Filtered Back Projection.
  Hamburger Beiträge zur Angewandten Mathematik (HBAM) 2017-05, 2017.
• Matthias Beckmann and Armin Iske
  Analysis of the Inherent Reconstruction Error in Filtered Back Projection.
  Hamburger Beiträge zur Angewandten Mathematik (HBAM) 2016-01, 2016.

Lecture Notes

• Matthias Beckmann
  Lecture Notes on Computerized Tomography.
  arXiv: 2312.02393.
  

Invited Talks

• Oberseminar: Optimization and Data Analysis (TUM2024)
  09. December 2024, Technische Universität München, München, Germany.
  Talk: On Modulo Radon Transform Based Tomography.
• IEEE International Workshop on Machine Learning for Signal Processing (MLSP2024)
  22. - 25. September 2024, London, GB.
  Talk: Equivariant Neural Networks for Indirect Measurements.
  Invited to Special Session on Learning-Based Solutions to Inverse Problems.
• 16th International Workshop on Document Analysis Systems (DAS2024)
  30. - 31. August 2024, Athens, Greece.
  Demo: On Image Processing and Pattern Recognition for Thermograms of Watermarks in Manuscripts - A First Proof-of-Concept.
  
• SIAM Conference on Imaging Science (IS2024)
  28. - 31. May 2024, Atlanta, US.
  Talk: Optimal Transport in Imaging and its Application to Thermography-Based Watermark Recognition.
  Invited to Minisymposium MS68: Computational Optimal Transport meets Imaging.
• 11th Applied Inverse Problems Conference (AIP2023)
  04. - 08. September 2023, Göttingen, Germany.
  Talk: Inversion of the Modulo Radon Transform via Orthogonal Matching Pursuit.
  Invited to Minisymposium MS22: Imaging with Non-Linear Measurements: Tomography and Reconstruction from Phaseless or Folded Data.
• 10th International Congress on Industrial and Applied Mathematics (ICIAM2023)
  21. - 25. August 2023, Tokyo, Japan.
  Talk: High Dynamic Range Tomography via Modulo Radon Transform.
  Invited to Minisymposium MS622: Inverse Problems and Imaging.
• SIAM Conference on Computational Sciences and Engineering (CSE2023)
  26. February - 3. March 2023, Amsterdam, Netherlands.
  Talk: High Dynamic Range Tomography via Modulo Radon Transform.
  Invited to Minisymposium MS61: Problems and Solutions in 3-D Reconstruction.
• Inverse Problems: Modelling and Simulation (IPMS2022)
  22. May - 28. May 2022, Mellieha, Malta.
  Talk: The Modulo Radon Transform and Its Inversion.
  Invited to Minisymposium M6: Generalized Radon Transforms and Applications.
• SIAM Conference on Imaging Science (IS2022)
  21. March - 25. March 2022, Berlin, Germany.
  Talk: The Modulo Radon Transform and Its Inversion.
  Invited to Minisymposium MS8: Tomographic Image Reconstruction with Radon-Type Transforms.
• Oberseminar: Mathematics of Data Analysis (TUM2017)
  18. May 2017, Technische Universität München, München, Germany.
  Talk: Sobolev Error Estimates for Filtered Back Projection Reconstructions.

Contributed Talks

• 10th International Conference on Scale Space and Variational Methods in Computer Vision (SSVM2025)
  18. - 22. May 2025, Totnes, UK.
  Talk: On an Analytical Inversion Formula for the Modulo Radon Transform.
  
• 10th International Conference on Scale Space and Variational Methods in Computer Vision (SSVM2025)
  18. - 22. May 2025, Totnes, UK.
  Poster: Max-Normalized Radon Cumulative Distribution Transform for Limited Data Classification.
  
• 18th International Conference on Document Analysis and Recognition (ICDAR2024)
  30. August - 04. September 2024, Athens, Greece.
  Poster: On Image Processing and Pattern Recognition for Thermograms of Watermarks in Manuscripts - A First Proof-of-Concept.
  
• Conference on Harmonic Analysis and Applications (Strobl2024)
  09. - 15. June 2024, Strobl, Austria.
  Poster: Fourier-Domain Inversion for the Modulo Radon Transform.
  
• SIAM Conference on Imaging Science (IS2024)
  28. - 31. May 2024, Atlanta, US.
  Poster: Inversion of the Modulo Radon Transform via Orthogonal Matching Pursuit.
  
• 94. Annual Meeting of GAMM (GAMM2024)
  18. - 22. March 2024, Magdeburg, Germany.
  Talk: Fourier-Domain Inversion for the Modulo Radon Transform.
  
• 93. Annual Meeting of GAMM (GAMM2023)
  30. May - 02. June 2023, Dresden, Germany.
  Talk: Inversion of the Modulo Radon Transform via Orthogonal Matching Pursuit.
  
• 92. Annual Meeting of GAMM (GAMM2022)
  15. - 19. August 2022, Aachen, Germany.
  Talk: High Dynamic Range Tomography via Modulo Radon Transform.
  
• Joint Annual Meeting of DMV and ÖMG (DMV2021)
  27. September - 01. October 2021, Passau, Germany.
  Talk: Error Analysis for Filtered Back Projection Reconstructions.
  
• SIAM Conference on Imaging Science (IS2020)
  06. - 17. July 2020, Toronto, Canada.
  Talk: High Dynamic Range Tomography via Modulo Radon Transform.
• 13th International Conference on Sampling Theory and Applications (SampTA2019)
  08. - 12. July 2019, Université de Bordeaux, Bordeaux, France.
  Talk: Convergence Rates for Hölder-Windows in Filtered Back Projection.
• 16th International Conference on Approximation Theory (AT2019)
  19. - 22. May 2019, Vanderbilt University, Nashville, TN, USA.
  Talk: Approximation of Bivariate Functions by Filtered Back Projection.
• Mecklenburg Workshop "Approximation Methods and Fast Algorithms" (MW2018)
  10. - 14. September 2018, University of Lübeck, Hasenwinkel, Germany.
  Talk: Saturation Rates for Filtered Back Projection.
• SIAM Conference on Imaging Science (IS2018)
  05. - 08. June 2018, Bologna, Italy.
  Talk: Error Analysis for Filtered Back Projection Reconstructions in Fractional Sobolev Spaces.
• YR Meeting & CSE Workshop "Recent Trends and Future Developments in Computational Science & Engineering" (CSE2018)
  26. - 29. March 2018, Technical University Hamburg, Plön, Germany.
  Talk: Saturation Rates for Filtered Back Projection Reconstructions.
• 89. Annual Meeting of GAMM (GAMM2018)
  19. - 23. March 2018, München, Germany.
  Talk: Saturation Rates for Filtered Back Projection Reconstructions.
• GAMM-MSIP Workshop on Mathematical Signal Processing and Data Analysis (GAMM-MSIP2017)
  18. - 20. September 2017, University of Bremen, Bremen, Germany.
  Talk: Error Analysis for Filtered Back Projection Reconstructions in Fractional Sobolev Spaces.
• 12th International Conference on Sampling Theory and Applications (SampTA2017)
  03. - 07. July 2017, Tallinn University, Tallinn, Estland.
  Talk: Sobolev Error Estimates for Filtered Back Projection Reconstructions.
• 88. Annual Meeting of GAMM (GAMM2017)
  06. - 10. March 2017, Weimar, Germany.
  Talk: Error Analysis for Filtered Back Projection Reconstructions in Fractional Sobolev Spaces.
• IM-Workshop on Signals, Images, and Approximation (IM2017)
  27. February - 03. March 2017, Bernried, Germany.
  Talk: Error Analysis for Filtered Back Projection Reconstructions in Fractional Sobolev Spaces.
• 27. Rhein-Ruhr-Workshop on Applied Analysis (RRW2017)
  27. - 28. January 2017, Bestwig, Germany.
  Poster: Analysis of the Inherent Reconstruction Error in Filtered Back Projection.
• International Workshop on Mathematical Imaging and Emerging Modalities (MIEM2016)
  27. - 30. June 2016, University of Osnabrück, Osnabrück, Germany.
  Talk: Analysis of the Inherent Reconstrution Error in Filtered Back Projection.
• SIAM Conference on Imaging Science (IS2016)
  23. - 26. May 2016, Albuquerque, NM, USA.
  Talk: Error Estimates and Convergence Rates for Filtered Back Projection.
• YR Meeting & CSE Workshop "Recent Trends and Future Developments in Computational Science & Engineering" (CSE2016)
  21. - 24. March 2016, University of Hamburg, Plön, Germany.
  Talk: On the Error Behaviour of the Filtered Back Projection.
• Annual Meeting of DMV and GAMM (GAMM2016)
  07. - 11. March 2016, Braunschweig, Germany.
  Talk: On the Error Behaviour of the Filtered Back Projection.
• IM-Workshop on Signals, Images, and Approximation (IM2016)
  29. February - 04. March 2016, Bernried, Germany.
  Talk: Error Estimates and Convergence Rates for Filtered Back Projection.
• 26. Rhein-Ruhr-Workshop on Applied Analysis (RRW2016)
  29. - 30. January 2016, Bestwig, Germany.
  Talk: Fehlerabschätzungen und Konvergenzraten für die gefilterte Rückwärtsprojektion.
• ICERM Workshop "Computational and Analytical Aspects of Image Reconstruction" (CAAIR2015)
  13. - 17. July 2015, Brown University, Providence, RI, USA.
  Poster: Error Estimates for Filtered Back Projection.
• 11th International Conference on Sampling Theory and Applications (SampTA2015)
  25. - 29. May 2015, American University, Washington, DC, USA.
  Talk: Error Estimates for Filtered Back Projection.
• YR Meeting & CSE Workshop "Recent Trends and Future Developments in Computational Science & Engineering" (CSE2015)
  09. - 13. March 2015, Christian-Albrechts-Universität zu Kiel, Plön, Germany.
  Talk: L² - Error Estimates for Filtered Back Projection.
• 25. Rhein-Ruhr-Workshop on Applied Analysis (RRW2015)
  30. - 31. January 2015, Bestwig, Germany.
  Talk: Fehlerabschätzungen für die gefilterte Rückwärtsprojektion.

Supervision of Student Theses

• 06/2025: Tom Bustert, M.Sc. Industrial Mathematics and Data Analysis, University of Bremen
  Learned Postprocessing Methods for Inverse Problems in the Context of Magnetic Particle Imaging
• 10/2024: Carla Dittert, M.Sc. Mathematics, University of Bremen
  Inversion of the Modulo Radon Transform via Laplacian Phase Unwrapping
• 08/2024: Jürgen Jeschke, M.Sc. Mathematics, University of Bremen
  Generalized Modulo Operators and Recovery Approaches for the Induced Modulo Radon Transform
• 09/2023: Lia Pribnow, M.Sc. Industrial Mathematics, University of Bremen
  The Radon Cumulative Distribution Transform in Image Classification
• 12/2022: Meira Iske, M.Sc. Mathematics, University of Bremen
  Inversion of the Modulo Radon Transform via Direct Fourier Reconstruction
• 11/2022: Nick Heilenkötter, M.Sc. Industrial Mathematics, University of Bremen
  Equivariant Neural Networks for Indirect Measurements
• 03/2021: Max Lewerenz, B.Sc. Mathematics, University of Hamburg
  Support vector machines from statistical learning theoretic point of view (in German)
• 06/2020: Tigran Andrikyan, B.Sc. Mathematics, University of Hamburg
  The short time Fourier transform and Gabor frames in time-frequency analysis (in German)

Courses at University of Bremen

• SoSe 2025: Approximation Theory
  Lecture and Exercise Class
• WiSe 2024/2025: Seminar on Mathematical Methods in Machine Learning
  Seminar (with Prof. Dr. Dr. h.c. Peter Maaß)
• WiSe 2024/2025: Advanced Topics in Image Processing - The Beauty of Variational Calculus
  Lecture (with Prof. Dr. Dr. h.c. Peter Maaß)
• SoSe 2024: Mathematical Foundations of Machine Learning
  Lecture
• WiSe 2023/2024: Inverse Problems in Imaging
  Lecture (with Prof. Dr. Dr. h.c. Peter Maaß)
• SoSe 2023: Mathematical Foundations of Machine Learning
  Lecture
• WiSe 2022/2023: Inverse Problems
  Lecture
• SoSe 2022: Mathematical Foundations of Machine Learning
  Lecture
• WiSe 2021/2022: Mathematical Methods for Signal and Image Processing
  Lecture
• SoSe 2021: Mathematical Foundations of Machine Learning
  Lecture and Exercise Class
• SoSe 2021: Mathematics 2b for Production Engineers
  Lecture

Courses at University of Hamburg

• WiSe 2020/2021: Computer Tomography
  Lecture
• WiSe 2020/2021: Approximation
  Lecture
• SoSe 2020: Project: Machine Learning
  Project
• WiSe 2019/2020: Computer Tomography
  Lecture and Exercise Class
• SoSe 2019: Functional Analysis
  Exercise Class
• WiSe 2018/2019: (Pro)Seminar über Approximation
  Seminar (with Prof. Dr. Armin Iske)
• WiSe 2017/2018: Approximation
  Exercise Class
• WiSe 2016/2017: Approximation
  Exercise Class
• WiSe 2015/2016: Approximation
  Exercise Class
• WiSe 2014/2015: Approximation
  Exercise Class

Courses at Technical University Hamburg

• SoSe 2020: Complex Functions
  Exercise Classes
• SoSe 2019: Complex Functions
  Exercise Classes
• WiSe 2018/2019: Differential Equations I
  Exercise Classes
• WiSe 2018/2019: Analysis III
  Exercise Classes
• SoSe 2018: Analysis II
  Exercise Classes
• WiSe 2017/2018: Analysis I
  Exercise Classes
• SoSe 2017: Complex Functions
  Exercise Classes
• WiSe 2016/2017: Analysis I
  Exercise Classes
• SoSe 2016: Complex Functions
  Exercise Classes
• WiSe 2015/2016: Differential Equations I
  Exercise Classes
• SoSe 2015: Analysis II
  Exercise Classes

My webhoster creates access logs containing date, time and accessed files as well as browser information and an anonymized IP address. The access logs will be automatically deleted within 8 weeks. Received emails will be deleted upon request.

Photo: Matthias Beckmann