Thorsten Theobald's publications

Recent work:

• Determining a rotation of a tetrahedron from a projection
  With R.J. Gardner and P. Gronchi.

• Amoebas of genus at most 1
  With T. de Wolff.

• Approximating amoebas and coamoebas by sums of squares
  With T. de Wolff.

• Projections of tropical varieties and their self-intersections
  With K. Hept.
  To appear in Advances in Geometry.

• Tropical combinatorics and genus of tropical intersections and Ehrhart theory
  With R. Steffens.
  SIAM J. Discrete Math. 24:17-32, 2010.

• Games of fixed rank: A hierarchy of bimatrix games
  With R. Kannan.
  Econom. Theory 42:157-173, 2010.

• Mixed volume techniques for embeddings of Laman graphs
  With R. Steffens.
  Computational Geometry: Theory and Applications 43:84-93, 2010.

• Book edited: Nonlinear Computational Geometry, IMA Volume, Springer, 2009
  With I. Emiris and F. Sottile.
  See Web page at Springer

• Tropical bases by regular projections
  With K. Hept.
  Proceedings of the American Mathematical Society 137:2233-2241, 2009

• Enumerating the Nash equilibria of rank 1-games
  In D. Avis, D. Bremner, A. Deza (eds.): Polyhedral Computation.
  AMS/CRM, 115-130, 2009.

• Book Algorithmische Geometrie: Polyedrische und algebraische Methoden, Vieweg-Verlag, 2008 (in German)
  With M. Joswig.
  See Web page at Vieweg

• Exploiting symmetries in SDP-relaxations for polynomial optimization
  With C. Riener, L. Jansson Andrén and J.B. Lasserre.

• Line problems in nonlinear computational geometry
  With F. Sottile.
  Surveys on Discrete and Computational Geometry: Twenty years later. Contemporary Mathematics, vol. 453, 411-432, AMS, 2008.

• Games of fixed rank: A hierarchy of bimatrix games
  With R. Kannan.
  Proc. Symposium on Discrete Algorithms (SODA 2007), New Orleans (LA), 1124-1132, 2007.

• Positive Polynome und semidefinite Optimierung (in German)
  With C. Riener.
  Jahresbericht der Deutschen Mathematiker-Vereinigung 110:57-76, 2007.
  

• On the frontiers of polynomial computations in tropical geometry
  Journal of Symbolic Computation 41:1360-1375, 2006.
  

• Radii minimal projections of polytopes and constrained optimization of symmetric polynomials
  With R. Brandenberg.
  Advances in Geometry 6:71-83, 2006.
  

• Geometrie und Kombinatorik von Nash-Gleichgewichten (in German)
  Mathematische Semesterberichte 52:221-239, 2005.

• On the complexity of visibility problems with moving viewpoints
  With P. Gritzmann.
  Combinatorial and Computational Geometry, MSRI publications, vol. 52, 377-397, Cambridge University Press, 2005.

• First steps in tropical geometry
  With J. Richter-Gebert and B. Sturmfels.
  In G.L. Litvinov, V.P. Maslov (eds.): Idempotent Mathematics and Mathematical Physics, Contemporary Mathematics, vol. 377, 289-317, AMS, 2005.
  

• Real k-flats tangent to quadrics in R^n
  With F. Sottile.
  Proceedings of the American Mathematical Society 133:2835-2844, 2005.

• Exact analysis of optimal configurations in radii computations
  With R. Brandenberg.
  European Workshop on Computational Geometry (Eindhoven), 135-138, 2005.

• Radii of simplices and some applications to geometric inequalities
  With R. Brandenberg.
  Beiträge zur Algebra und Geometrie 45:581-594, 2004.
  Additional pictures of the Weißbach polytope: JPEG, Javaview 3D model, input data for Geomview.
• Algebraic methods for computing smallest enclosing and circumscribing cylinders of simplices
  With R. Brandenberg.
  Applicable Algebra in Engineering, Communication and Computing 14:439-460, 2004.

• Common transversals and tangents to two lines and two quadrics in P^3
  With G. Megyesi and F. Sottile.
  Discrete and Computational Geometry 30:543-571, 2003.
  Accompanying Web page
  

• Visibility computations: From discrete algorithms to real algebraic geometry
  In S. Basu and L. Gonzalez-Vega (eds.), Algorithmic and Quantitative Real Algebraic Geometry, AMS DIMACS series, vol. 60, 207-219, 2003

• Homotopy methods for real-time visualization of geometric tangent problems
  With D. Kotzor.
  Video presentation, ACM Symposium on Computational Geometry 2002 (Barcelona). Accompanying article in the proceedings, pp. 275-276

• Lines tangent to 2n-2 spheres in R^n
  With F. Sottile.
  Accompanying Web page
  Transactions of the AMS 354(12):4815-4829, 2002
  

• Computing amoebas
  Experimental Mathematics 11:513-526, 2002
  

• An enumerative geometry framework for algorithmic line problems in R^3
  SIAM Journal on Computing 31(4), pp. 1212-1228, 2002

• How to realize a given number of tangents to four unit balls in R^3
  Mathematika 48:51-62, 2001

• Common tangents to four unit balls in R^3
  With I.G. Macdonald and J. Pach.
  Discrete and Computational Geometry 26(1), pp. 1-17, 2001
  

Some former work (list not complete):

• Local encoding transformations for optimizing OBDD-representations of finite state machines.
  With Ch. Meinel.
  Formal Methods in System Design 18, pp. 285-301 (2001)

• Linear sifting of decision diagrams and its application in synthesis
  IEEE Transactions on Computer-Aided Design 19(5), pp. 521-533 (2000)

• Ordered binary decision diagrams and their significance in computer-aided design of VLSI circuits.
  With Ch. Meinel.
  Journal of Circuits, Systems, and Computers 9(3 & 4), pp. 181-198 (1999)

• On the influence of the state encoding on OBDD-representations of finite state machines.
  With Ch. Meinel.
  Theoretical Informatics and Applications 33(1), pp. 21-31 (1999)

• How to break Shamir's asymmetric basis.
  In Advances in Cryptology: Proceedings of CRYPTO '95 (Santa Barbara)
  Springer Lecture Notes in Computer Science, Vol. 963, pp. 136-147 (1995)

Habilitation thesis:

• New Algebraic Methods in Computational Geometry.

Book:

• Algorithms and Data Structures in VLSI Design: OBDD - Foundations and Applications.
  With Ch. Meinel.
  Springer (1998)