Real Algebraic Geometry With A View Toward Systems Control and Free Positivity

7-11 April 2014
Mathematisches Forschungsinstitut Oberwolfach (MFO), Germany.


This is a workshop organized by Didier Henrion, Salma Kulhmann and Victor Vinnikov, jointly with the 4th official meeting of the GeoLMI project funded by the French National Research Agency.

Date and venue

The workshop takes place from Monday 7 April to Friday 11 April 2014 at MFO, Oberwolfach, Germany.

Scientific programme

Monday April 7

  • 9.15-10.05. Jean-Bernard Lasserre (LAAS-CNRS Univ. Toulouse, FR). On LP and SDP certificates of positivity.

  • 10.25-11.15. Markus Schweighofer (Univ. Konstanz, DE). Positive polynomials, sums of squares, degree bounds and semidefinite representations.

  • 11.35-12.25. Konrad Schmudgen (Univ. Leipzig, DE). Noncommutative positivity and Positivstellensatze.

  • 16.00-16.40. Amir Ali Ahmadi (IBM New York, USA). Computation of the joint spectral radius with optimization techniques.

  • 16.55-17.35. Jaka Cimpric (Univ. Ljubljana, SI). Positive matrix polynomials.

  • 17.50-18.30. Jean Valles (Univ. Pau, FR). Freeness of line arrangements.

    Tuesday April 8

  • 9.15-10.05. Peter Branden (KTH Stockholm, SE). Hyperbolic polynomials and spectrahedral cones.

  • 10.25-11.15. J. William Helton (Univ. California San Diego, USA). Free real algebraic geometry and linear matrix inequalities.

  • 11.35-12.25. Murray Marshall (Univ. Saskatchewan, CA). Real algebraic geometry, positive polynomials and moments.

  • 16.00-16.40. Tim Netzer (Univ. Leipzig, DE). Positivstellensaetze in graph theory.

  • 16.55-17.35. Christoph Hanzelka (Univ. Konstanz, DE). Real symmetric determinantal representations of ternary hyperbolic polynomials.

  • 17.50-18.30. Eli Shamovich (Ben Gurion Univ. Negev, IL). Determinantal representations of space curves.

    Wednesday April 9

  • 9.15-10.05. Joe Ball (Virginia Inst. Tech., USA). Noncommutative functions and balls and robust control.

  • 10.25-11.15. Yosef Yomdin (Weizemann Inst., IL). Vanishing of polynomial moments and iterated integrals.

  • 11.35-12.25. Mohab Safey El Din (Univ. Pierre et Marie Curie Paris, FR). (Exact) algorithms for real algebraic geometry.

    Thursday April 10

  • 9.15-10.05. Bruce Reznick (Univ. Illinois Urbana-Champaign, USA). Some old and new examples and results involving psd forms that are not sos.

  • 10.25-11.15. Hugo Woerdeman (Drexel Univ., USA). The autoregressive filter problem in two variables and related problems.

  • 11.35-12.25. Bernard Mourrain (INRIA Mediterannee, FR). Can moment relaxation methods solve (efficiently) polynomial optimization problems ?

  • 16.00-16.40. Ken J. Dykema (Texas A&M Univ., USA). Singular numbers and products of operators.

  • 16.55-17.35. Maria Infusino (Univ. Reading, UK). The moment problem on infinite-dimensional basic semi-algebraic sets.

  • 17.50-18.30. Andreas Thom (Univ. Leipzig, DE). Noncommutative real algebraic geometry and application to group rings.

    Friday April 11

  • 9.15-9.55. Greg Blekherman (Georgia Inst. Tech., USA). Degree bounds in rational sums of squares representations.

  • 10.05-10.45. Mario Kummer (Univ. Konstanz, DE). Determinantal representations of hyperbolic polynomials.

  • 10.55-11.35. Roland Hildebrand (LJK-CNRS Univ. Grenoble, FR). Spectrahedral cones generated by rank-one matrices.

  • 11.45-12.25. Michael A. Dritschel (Newcastle Univ., UK). Realizations via pre-orderings with applications to the Schur class.

  • 16.00-16.40. Sabine Burgdorf (CWI Amsterdam, NL). Free polynomial optimization.

  • 16.55-17.35. Frank Vallentin (Univ. Koeln, DE). Invariant sums of squares.

  • 17.50-18.30. Raman Sanyal (Tech. Univ. Berlin, DE). Theta ranks and matroid minors.

    Last updated on 13 April 2014.