Abstract
The first secant variety of a projective monomial curve is a threefold with an action by a one-dimensional torus. Its tropicalization is a three-dimensional fan with a one-dimensional lineality space, so the tropical threefold is represented by a balanced graph. Our main result is an explicit construction of that graph. As a consequence, we obtain algorithms to effectively compute the multidegree and Chow polytope of an arbitrary projective monomial curve. This generalizes an earlier degree formula due to Ranestad. The combinatorics underlying our construction is rather delicate, and it is based on a refinement of the theory of geometric tropicalization due to Hacking, Keel and Tevelev.
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Bieri R., Groves J.: The geometry of the set of characters induced by valuations. J. Reine Angew. Math. 347, 168–195 (1984)
Bogart T., Jensen A.N., Speyer D., Sturmfels B., Thomas R.R.: Computing tropical varieties. J. Symb. Comput. 42, 54–73 (2007)
Catalano-Johnson M.L.: The possible dimensions of the higher secant varieties. Am. J. Math. 118, 355–361 (1996)
Conca A.: Straightening law and powers of determinantal ideals of Hankel matrices. Adv. Math. 138, 263–292 (1998)
Cox D., Sidman J.: Secant varieties of toric varieties. J. Pure Appl. Algebra 209, 651–669 (2007)
Cueto, M.A.: Implicitization of surfaces via geometric tropicalization. arXiv:1105.0509, (2011)
Cueto M.A., Tobis E.A., Yu J.: An implicitization challenge for binary factor analysis. J. Symb. Comput. 45, 1296–1315 (2010)
De Concini C., Procesi C.: Wonderful models of subspace arrangements. Sel. Math. (N.S.) 1, 459–494 (1995)
De Loera, J.A., Haws, D., Hemmecke, R., Huggins, P., Tauzer, J., Yoshida, R.: A user’s guide for LattE v1.1.http://www.math.ucdavis.edu/~latte (2003)
Develin M.: Tropical secant varieties of linear spaces. Discrete Comput. Geom. 35, 117–129 (2006)
Dickenstein A., Feichtner E.M., Sturmfels B.: Tropical discriminants. J. Am. Math. Soc. 20, 1111–1133 (2007) (electronic)
Draisma J.: A tropical approach to secant dimensions. J. Pure Appl. Algebra 212, 349–363 (2008)
Dvornicich R., Zannier U.: Newton functions generating symmetric fields and irreducibility of Schur polynomials. Adv. Math. 222, 1982–2003 (2009)
Einsiedler M., Kapranov M., Lind D.: Non-Archimedean amoebas and tropical varieties. J. Reine Angew. Math. 601, 139–157 (2006)
Fink, A.: Tropical cycles and Chow polytopes. Beitr. Algebra Geom. arXiv:1001.4784v2 (2012)
Hacking P., Keel S., Tevelev J.: Stable pair, tropical, and log canonical compactifications of moduli spaces of del Pezzo surfaces. Invent. Math. 178, 173–227 (2009)
Harris, J.: Algebraic geometry. A first course. Graduate Texts in Mathematics, vol. 133. Springer, New York (1995) (Corrected reprint of the 1992 original)
Moci L.: Wonderful models for toric arrangements. Int. Math. Res. Not. 2012, 213–238 (2012)
Ranestad K.: The degree of the secant variety and the join of monomial curves. Collect. Math. 57, 27–41 (2006)
Sturmfels B., Tevelev J.: Elimination theory for tropical varieties. Math. Res. Lett. 15, 543–562 (2008)
Sturmfels B., Tevelev J., Yu J.: The Newton polytope of the implicit equation. Mosc. Math. J. 7, 327–346 (2007)
Valla G.: On determinantal ideals which are set-theoretic complete intersections. Compositio Math. 42, 3–11 (1980/1981)
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M. A. Cueto was supported by a UC Berkeley Chancellor’s Fellowship and by an NSF postdoctoral fellowship DMS-1103857 and S. Lin was supported by a Singapore A*STAR Fellowship.
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Cueto, M.A., Lin, S. Tropical secant graphs of monomial curves. Beitr Algebra Geom 54, 383–418 (2013). https://doi.org/10.1007/s13366-012-0091-9
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DOI: https://doi.org/10.1007/s13366-012-0091-9