Abstract
We prove constructively that: The complement\({{\mathbb {R}}}^n{\setminus }\mathcal {K}\)of ann-dimensional unbounded convex polyhedron\(\mathcal {K}\subset {{\mathbb {R}}}^n\)and the complement\({{\mathbb {R}}}^n{\setminus }{\text {Int}}(\mathcal {K})\)of its interior are polynomial images of\({{\mathbb {R}}}^n\)whenever\(\mathcal {K}\)does not disconnect\({{\mathbb {R}}}^n\). The case of a compact convex polyhedron and the case of convex polyhedra of small dimension were approached by the authors in previous works. The techniques here are more sophisticated than those corresponding to the compact case and require rational separation results for tuples of variables, which have interest by their own and can be applied to separate certain types of (non-compact) semialgebraic sets.








Similar content being viewed by others
References
Acquistapace, F., Andradas, C., Broglia, F.: Separation of semialgebraic sets. J. Am. Math. Soc. 12(3), 703–728 (1999)
Basu, S., Pollack, R., Roy, M.-F.: Algorithms in Real Algebraic Geometry. Algorithms and Computation in Mathematics, vol. 10, 2nd edn. Springer, Berlin (2006)
Berger, M.: Geometry I & II. Universitext. Springer, Berlin (1987)
Bing, R.H.: Generalizations of two theorems of Janiszewski. Bull. Am. Math. Soc. 51(12), 954–960 (1945)
Bochnak, J., Coste, M., Roy, M.F.: Real Algebraic Geometry. Ergebnisse der Mathematik und ihrer Grenzgebiete, vol. 36. Springer, Berlin (1998)
Eisenbud, D.: Open problems in computational algebraic geometry. In: Eisenbud, D., Robbiano, L. (eds.) Computational Algebraic Geometry and Commutative Algebra. Symposia Mathematica, vol. 34, pp. 49–70. Cambridge University Press, Cambridge (1993)
Fawzi, H.: On polyhedral approximations of the positive semidefinite cone. arXiv:1811.09649 (2018)
Fernando, J.F.: On the one dimensional polynomial and regular images of \({\mathbb{R}}^n\). J. Pure Appl. Algebra 218(9), 1745–1753 (2014)
Fernando, J.F.: On Nash images of Euclidean spaces. Adv. Math. 331, 627–719 (2018)
Fernando, J.F., Fichou, G., Quarez, R., Ueno, C.: On regulous and regular images of Euclidean spaces. Q. J. Math. 69(4), 1327–1351 (2018)
Fernando, J.F., Gamboa, J.M.: Polynomial images of \({\mathbb{R}}^n\). J. Pure Appl. Algebra 179(3), 241–254 (2003)
Fernando, J.F., Gamboa, J.M.: Polynomial and regular images of \({\mathbb{R}}^n\). Israel J. Math. 153, 61–92 (2006)
Fernando, J.F., Gamboa, J.M., Ueno, C.: On convex polyhedra as regular images of \({\mathbb{R}}^n\). Proc. Lond. Math. Soc. 103(5), 847–878 (2011)
Fernando, J.F., Gamboa, J.M., Ueno, C.: The open quadrant problem: a topological proof. In: A Mathematical Tribute to Professor José María Montesinos Amilibia. Dep. Geom. Topol. Fac. Cien. Mat., pp. 337–350. UCM, Madrid (2016)
Fernando, J.F., Gamboa, J.M., Ueno, C.: Polynomial, regular and Nash images of Euclidean spaces. In: Broglia, F., et al. (eds.) Ordered Algebraic Structures and Related Topics. Contemporary Mathematics, vol. 697, pp. 145–167. American Mathematical Society, Providence (2017)
Fernando, J.F., Gamboa, J.M., Ueno, C.: Unbounded convex polyhedra as polynomial images of Euclidean spaces. Ann. Sc. Norm. Super. Pisa Cl. Sci. 19(2), 509–565 (2019)
Fernando, J.F., Ueno, C.: On the set of points at infinity of a polynomial image of \({\mathbb{R}}^n\). Discrete Comput. Geom. 52(4), 583–611 (2014)
Fernando, J.F., Ueno, C.: On complements of convex polyhedra as polynomial and regular images of \({\mathbb{R}}^n\). Int. Math. Res. Not. IMRN 2014(18), 5084–5123 (2014)
Fernando, J.F., Ueno, C.: On the complements of 3-dimensional convex polyhedra as polynomial images of \({\mathbb{R}}^3\). Int. J. Math. 25(7), 1450071 (2014)
Fernando, J.F., Ueno, C.: A short proof for the open quadrant problem. J. Symb. Comput. 79(1), 57–64 (2017)
Föllmer, H., Schied, A.: Stochastic Finance: An Introduction in Discrete Time. de Gruyter Studies in Mathematics, vol. 27, 2nd edn. de Gruyter, Berlin (2004)
Gamboa, J.M.: Reelle Algebraische Geometrie. June, 10th–16th. Oberwolfach (1990)
González-López, M.J., Recio, T., Santos, F.: Parametrization of semialgebraic sets. Math. Comput. Simul. 42(4–6), 353–362 (1996)
Handelman, D.: Representing polynomials by positive linear functions on compact convex polyhedra. Pac. J. Math. 132(1), 35–62 (1988)
Janiszewski, Z.: Sur les coupures du plan faites par les continus. Prace Mat.-Fiz. 26, 11–63 (1913)
Kubjas, K., Parrilo, P.A., Sturmfels, B.: How to flatten a soccer ball. In: Conca, A., Gubeladze, J., Römer, T. (eds.) Homological and Computational Methods in Commutative Algebra. Springer INdAM Series, vol. 20, pp. 141–162. Springer, Cham (2017)
Nie, J., Demmel, J., Sturmfels, B.: Minimizing polynomials via sum of squares over the gradient ideal. Math. Program. 106(3), 587–606 (2006)
Parrilo, P.A., Sturmfels, B.: Minimizing polynomial functions. In: Basu, S., Gonzalez-Vega, L. (eds.) Algorithmic and Quantitative Real Algebraic Geometry. DIMACS Series in Discrete Mathematics and Theoretical Computer Science, vol. 60, pp. 83–99. American Mathematical Society, Providence (2003)
Rockafellar, T.R.: Convex Analysis. Princeton Mathematical Series, vol. 28. Princeton University Press, Princeton (1970)
Schweighofer, M.: Global optimization of polynomials using gradient tentacles and sums of squares. SIAM J. Optim. 17(3), 920–942 (2006)
Stengle, G.: A Nullstellensatz and a Positivstellensatz in semialgebraic geometry. Math. Ann. 207, 87–97 (1974)
Ueno, C.: A note on boundaries of open polynomial images of \({\mathbb{R}}^2\). Rev. Mat. Iberoam. 24(3), 981–988 (2008)
Ueno, C.: On convex polygons and their complements as images of regular and polynomial maps of \({\mathbb{R}}^2\). J. Pure Appl. Algebra 216(11), 2436–2448 (2012)
Vui, Hà Huy, So’n, Phạm Tiên: Global optimization of polynomials using the truncated tangency variety and sums of squares. SIAM J. Optim. 19(2), 941–951 (2008)
Yannakakis, M.: Expressing combinatorial optimization problems by linear programs. J. Comput. Syst. Sci. 43(3), 441–466 (1991)
Ziegler, G.M.: Lectures on Polytopes. Graduate Texts in Mathematics, vol. 152. Springer, New York (1995)
Acknowledgements
The authors are strongly indebted with the anonymous referees for their suggestions that have helped them to improve significantly the final version of this article.
Author information
Authors and Affiliations
Corresponding author
Additional information
Editor in Charge: Kenneth Clarkson
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
The first author (J.F. Fernando) is supported by Spanish GRAYAS MTM2014-55565-P, Spanish STRANO MTM2017-82105-P and Grupos UCM 910444, whereas the second author (C. Ueno) is an external collaborator of the first two grants. This work was also partially supported by the “National Group for Algebraic and Geometric Structures and their Applications” (GNSAGA - INdAM). This article was partially written during a common one year research stay of the authors in the Dipartimento di Matematica of the Università di Pisa. The authors would like to thank the department for the invitation and the very pleasant working conditions. The one year research stay of the first author was partially supported by MECD grant PRX14/00016. The one year research stay of the second author was mainly supported by ‘Scuola Galileo Galilei’ Research Grant at the Dipartimento di Matematica of the Università di Pisa (D.R. n\(^{\text {o}}\)27519 of 29/07/2013, MAT/03).
Rights and permissions
About this article
Cite this article
Fernando, J.F., Ueno, C. Complements of Unbounded Convex Polyhedra as Polynomial Images of \({{\mathbb {R}}}^n\). Discrete Comput Geom 62, 292–347 (2019). https://doi.org/10.1007/s00454-019-00065-2
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00454-019-00065-2
Keywords
- Semialgebraic sets
- Polynomial maps and images
- Complement of a convex polyhedra
- Rational separation of tuples of variables