Dr. Sven Herrmann sherrmann [at] mathematik.tu-darmstadt.de  since April 2010 at: School of Computing Science, University of East Anglia, Norwich, NR4 7TJ, UK phone: +44 1603 592906 room: BIO 2.02 http://www.mathematik.tu-darmstadt.de/~sherrmann/

Research Interests:

• discrete geometry, especially subdivisions of polytopes,
• computational biology, 
• phylogenetics,
• computational geometry,
• tropical geometry,
• mathematical software,
• related topics in combinatorics, algebraic geometry, commutative algebra, ...

Publications:

• Dressians, Tropical Grassmannians, and Their Rays (with Michael Joswig and David Speyer), preprint, 2012, arXiv:1112.1278.
• Optimal Realisations of Two-Dimensional, Totally-Decomposable Metrics (with Jack Koolen, Alice Lesser, Vincent Moulton and Taoyang Wu), preprint, 2011, arXiv:1108.0290.
• Recognizing Treelike k-Dissimilarities (with Katharina Huber, Vincent Moulton and Andreas Spillner), 2011, to appear in Journal of Classification.
• Computing the Bounded Subcomplex of an Unbounded Polyhedron (with Michael Joswig and Marc Pfetsch), Computational Geometry: Theory and Applications (2011), doi:10.1016/j.comgeo.2011.11.002.
• On the Facets of the Secondary Polytope,  Journal of Combinatorial Theory, Series A, 118 (2011), no.2, 425-447.
• Trees, Tight-Spans and Point Configurations (with Vincent Moulton), preprint, 2011, arXiv:1104.1538.
• The Split Decomposition of a k-Dissimilarity Map (with Vincent Moulton), preprint, 2010, arXiv:1008.1703, to appear in Advances of Applied Mathematics.
• Totally Splittable Polytopes (with Michael Joswig), Discrete & Computational Geometry, 44 (2010), no.1, 149-166.
• How to Draw Tropical Planes (with Anders Jensen, Michael Joswig and Bernd Sturmfels), Electronic Journal of Combinatorics, 16 (2009),  no.2  (Björner Festschrift volume), #R6.
• Tight Spans and Coarsest Subdivisions of Convex Polytopes, Proceedings of the 25th European Workshop on Computational Geometry (2009), 259-262.
• Splitting Polytopes (with Michael Joswig), Münster Journal of Mathematics, 1 (2008), 109-142.
• Genocchi Numbers and f-Vectors of Simplicial Balls, European Journal of Combinatorics, 29 (2008), no. 5, 1087-1091.
• Bounds on the f-Vectors of Tight Spans (with Michael Joswig), Contributions to Discrete Mathematics, 2 (2007), no. 2, 161-184.

Software:

• Several contributions to the mathematical software system polymake by Michael Joswig and Ewgenij Gawrilow. 

PhD Thesis:

• Splits and Tight Spans of Convex Polytopes (download), TU Darmstadt, 2009, Verlag Dr. Hut. Supervisor: Michael Joswig

Teaching: 

• WS 2009/2010: Mathematik I für Informatik (Prof. Dr. Thomas Streicher, Dr. Sven Herrmann, Dipl.-Math. Susanne Pape)
• SS 2009: Algorithmische Diskrete Mathematik (PD Dr. Raymond Hemmecke, Dr. Sven Herrmann)
• WS 2008/2009: Algorithmische Geometrie (PD Dr. Raymond Hemmecke, Sven Herrmann)
• WS 2007/2008: Introduction to Mathematical Software (Prof. Dr. Michael Joswig, Dr. Ulf Lorenz)
• SS 2007: Nichtlineare algorithmische Geometrie (Prof. Dr. Michael Joswig, Sven Herrmann)
• WS 2006/2007: Linear Algebra I for MCS (Prof. Dr. Martin Otto, Dr. Benno van den Berg, Sven Herrmann)
• SS 2006: Analysis II for MCS (Dr. Laurentiu Leustean, Eyvind Briseid, Sven Herrmann)
• SS 2006: Diskrete Mathematik (Prof. Dr. Michael Joswig, Katja Kulas)

Past Projects: 

• WS 2005/2006: Delaunay triangulations for linearisation of non-linear functions as part of Transient Gas Network Optimization.
• Diploma Thesis: Kombinatorik von Hypersimplex-Triangulierungen, October 2005 (supervised by Michael Joswig).