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Publications - Tim Netzer
All publications available via arXiv
- A Note on the Caratéodory Number of the Joint Numerical Range, with B. Maier
- Self-Dual Cone Systems and Tensor Products
- Positive Moments Forever: Undecidable and Decidable Cases, with G. De les Coves and A. Klingler
- Homotopy Methods for Convex Optimization, with A. Klingler
- Beyond Operator Systems, with G. De les Coves and Mirte van der Eyden
- Border Ranks of Positive and Invariant Tensor Decompositions: Applications to Correlations, with G. De les Coves and A. Klingler
- Zahlen und Algebra. Ein Kurs im Lehramtsstudium, with J. Frischauf, Springer Spektrum (2024)
- Geometry of Linear Matrix Inequalities, with D. Plaumann, Compact Textbooks in Mathematics, Birkhäuser (2023)
- Polynomial Decompositions with Invariance and Positivity Inspired by Tensors, with G. De las Cuevas and A. Klingler, Linear Algebra and its Applications 698, 537-588 (2024)
- A Note on Polynomial Equations over Algebras, with M. Illmer, Proceedings of the American Mathematical Society 152 (5), 1831–1839 (2024)
- Classifying Linear Matrix Inequalities via Abstract Operator Systems, with M. Berger and T. Drescher, Linear Algebra and its Applications 682, 28–49 (2024)
- Tensor Decompositions on Simplicial Complexes with Invariance, with G. De las Cuevas and M. Hoogsteder Riera, Journal of Symbolic Computation 124, 102299 (2024)
- Approximate Completely Positive Semidefinite Factorizations and Their Ranks, with P. Abbasi and A. Klingler, Linear Algebra and its Applications 677, 323-336 (2023)
- Abstract Operator Systems over the Cone of Positive Semidefinite Matrices, with M. Berger, Journal of Operator Theory 90 (2), 101–120 (2023)
- Magic Squares: Latin, Semiclassical and Quantum, with G. De las Cuevas and I. Valentiner-Branth, Journal of Mathematical Physics 64, 022201 (2023)
- Approximate Pythagoras Numbers, with P. Abbasi, S. Gribling and A. Klingler, Journal of Complexity 74, 101698 (2023)
- On Projections of Free Semialgebraic Sets, with T. Drescher and A. Thom, Advances in Geometry 23 (2), 207–214 (2023)
- Halos and Undecidability of Tensor Stable Positive Maps, with G. De las Cuevas and M. van der Eyden, Journal of Physics A: Mathematical and Theoretical 55, 264006 (2022), also accepted for a talk at QPL 2022
- Cats Climb Entails Mammals Move: Preserving Hyponymy in Compositional Distributional Semantics, with G. De las Cuevas, A. Klingler and M. Lewis, Journal of Cognitive Science 22 (3), 311-353 (2021)
- Approximate Tensor Decompositions: Disappearance of many Separations, with G. De las Cuevas and A. Klingler, Journal of Mathematical Physics 62, 093502 (2021) Editor's Pick
- Quantum Information Theory and Free Semialgebraic Geometry: One Wonderland Through Two Looking Glasses, with G. De Las Cuevas, Internationale Mathematische Nachrichten 246, 1-29 (2021)
- A Note on Noncommutative Polytopes and Polyhedra, with B. Huber, Advances in Geometry 21 (1), 119-124 (2021)
- Quantum Magic Squares: Dilations and Their Limitations, with G. De las Cuevas and T. Drescher, Journal of Mathematical Physics 61, 111704 (2020) Editor's Pick
- Mixed States in One Spatial Dimension: Decompositions and Correspondence with Nonnegative Matrices, with G. De las Cuevas, Journal of Mathematical Physics 61, 041901 (2020)
- Optimal Bounds on the Positivity of a Matrix from a few Moments, with G. De las Cuevas and T. Fritz, Communications in Mathematical Physics 375, 105-126 (2020)
- Separability for Mixed States with Operator Schmidt Rank Two, with G. De las Cuevas and T. Drescher, Quantum 3, 203 (2019)
- Quadratic Modules, C*-Algebras, and Free Convexity, with V. Alekseev and A. Thom, Transactions of the American Mathematical Society 372 (11), 7525-7539 (2019)
- Free Semialgebraic Geometry, Internationale Mathematische Nachrichten 240, 31–41 (2019)
- Non-Nudgable Subgroups of Permutations, Archiv der Mathematik 109 (5), 401-406 (2017)
- Spectrahedral Containment and Operator Systems with Finite-Dimensional Realization, with T. Fritz and A. Thom, SIAM Journal on Applied Algebra and Geometry 1, 556-574 (2017)
- About the Solvability of Matrix Polynomial Equations, with A. Thom, Bulletin of the London Mathematical Society 49, 670-675 (2017)
- Real Algebraic Geometry and its Applications, Internationale Mathematische Nachrichten 232, 1-18 (2016)
- Kazhdan’s Property (T) via Semidefinite Optimization, with A. Thom, Experimental Mathematics 24 (2), 1-4 (2015)
- Positivstellensätze for Quantum Multigraphs, with Andreas Thom, Journal of Algebra 422, 504-519 (2015)
- Can You Compute the Operator Norm? with T. Fritz and A. Thom, Proceedings of the American Mathematical Society 142 (12), 4265-4276 (2014)
- Hyperbolic Polynomials and Generalized Clifford Algebras, with A. Thom, Discrete & Computational Geometry 51 (4), 802-814 (2014)
- Smooth Hyperbolicity Cones are Spectrahedral Shadows, with R. Sanyal, Mathematical Programming Series B Special Issue on Lifts of Convex Sets (2014)
- How Fast Do Polynomials Grow on Semialgebraic Sets? with Pinaki Mondal, Journal of Algebra 413, 320-344 (2014)
- Determinantal Representations and the Hermite Matrix, with D. Plaumann and A. Thom, Michigan Mathematical Journal 62 (2), 407-420 (2013)
- Real Closed Separation Theorems and Applications in Group Algebras, with A. Thom, Pacific Journal of Mathematics 263 (2), 435-452 (2013)
- Polynomials with and without Determinantal Representations, with A. Thom, Linear Algebra and its Applications 437 (7), 1579-1595 (2012)
- Positivstellensätze for Real Function Algebras, with M. Marshall, Mathematische Zeitschrift 270 (3-4), 889-901 (2012)
- Positive Polynomials and Projections of Spectrahedra, with J. Gouveia, Siam Journal on Optimization 21 (3), 960-976 (2011)
- On the Real Multidimensional Rational K-Moment Problem, with J. Cimprič and M. Marshall, Transactions of the American Mathematical Society 363 (11), 5773-5788 (2011)
- Closures of Quadratic Modules, with J. Cimprič and M. Marshall, Israel Journal of Mathematics 183 (1), 445-474 (2011)
- Tracial Algebras and an Embedding Theorem, with A. Thom, Journal of Functional Analysis 259, 2939-2960 (2010)
- Representation and Approximation of Positivity Preservers, Journal of Geometric Analysis 20 (3), 751-770 (2010)
- On Semidefinite Representations of Non-Closed Sets, Linear Algebra and its Applications 432, 3072-3078 (2010)
- Exposed Faces of Semidefinitely Representable Sets, with D. Plaumann and M. Schweighofer, Siam Journal on Optimization 20 (4), 1944-1955 (2010)
- Positive Polynomials and Sequential Closures of Quadratic Modules, Transactions of the American Mathematical Society 362, 2619-2639 (2010)
- Stability of Quadratic Modules, manuscripta mathematica 129 (2), 251-271 (2009)
- An Elementary Proof of Schmüdgen’s Theorem on the Moment Problem of Closed Semi-Algebraic Sets, Proceedings of the American Mathematical Society 136, 529-537 (2008)
- A Note on the Representation of Positive Polynomials with Structured Sparsity, with D. Grimm and M. Schweighofer, Archiv der Mathematik 89 (5), 399-403 (2007)
- SOS Approximations of Nonnegative Polynomials via Simple High Degree Pertubations, with J.B. Lasserre, Mathematische Zeitschrift 256 (1), 99-112 (2007)
- Buchbesprechung: Mateusz Michałek, Bernd Sturmfels: Invitation to Nonlinear Algebra, Mathematische Semesterberichte 70, 61–62 (2023)
- Magic Squares: A children’s puzzle meets quantum physics, with Gemma De las Cuevas and Tom Drescher, The Science Breaker, May 2022
- Spectrahedra and Their Shadows, Habilitation Thesis, University of Leipzig, October 2011
- Positive Polynomials, Sums of Squares and the Moment Problem, Doctoral Thesis, University of Konstanz, July 2008
- High Degree Perturbations of Nonnegative Polynomials, Diploma Thesis, University of Konstanz, June 2005