Polarization of Separating Invariants
Canadian journal of mathematics, Tome 60 (2008) no. 3, pp. 556-571

Voir la notice de l'article provenant de la source Cambridge University Press

We prove a characteristic free version of Weyl’s theorem on polarization. Our result is an exact analogue of Weyl’s theorem, the difference being that our statement is about separating invariants rather than generating invariants. For the special case of finite group actions we introduce the concept of cheap polarization, and show that it is enough to take cheap polarizations of invariants of just one copy of a representation to obtain separating vector invariants for any number of copies. This leads to upper bounds on the number and degrees of separating vector invariants of finite groups.
DOI : 10.4153/CJM-2008-027-2
Mots-clés : 13A50, 14K24
Draisma, Jan; Kemper, Gregor; Wehlau, David. Polarization of Separating Invariants. Canadian journal of mathematics, Tome 60 (2008) no. 3, pp. 556-571. doi: 10.4153/CJM-2008-027-2
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[1] [1] Bosma, W., Cannon, J. J., and Playoust, C., The Magma algebra system i: the user language. J. Symb. Comput. 24(1997), no. 3-4, 235–265. Google Scholar

[2] [2] Derksen, H. and Kemper, G., Computational invariant theory. Encyclopaedia of Mathematical Sciences 130, Springer-Verlag, Berlin, 2002. Google Scholar

[3] [3] Kemper, G., Computing invariants of reductive groups in positive characteristic. Transform. Groups 8(2003), no. 2, 159–176. Google Scholar

[4] [4] Knop, F., On Noether's and Weyl's bound in positive characteristic. In: Invariant Theory in All Characteristics, CRM Proc. Lecture Notes 35, American Mathematical Society, Providence, RI, 2004, pp. 175–188. Google Scholar

[5] [5] Kraft, H. and Procesi, C., A Primer of Invariant Theory. Notes by G. Boffi, Brandeis Lecture Notes 1, 1982. Updated version (2000) available at http://www.math.unibas.ch/˜ kraft/Papers/KP-Primer.pdf. Google Scholar

[6] [6] Losik, M., Michor, P.W., and Popov, V. L., On polarizations in invariant theory. J. Algebra 301(2006), no. 1, 406–424. Google Scholar

[7] [7] Richman, D. R., On vector invariants over finite fields. Adv. Math. 81(1990), no. 1, 30–65. Google Scholar

[8] [8] Richman, D. R., Invariants of finite groups over fields of characteristic p. Adv. in Math. 124(1996), no. 1, 25–48. Google Scholar

[9] [9] Weyl, H., The Classical Groups. Their Invariants and Representations, Princeton University Press, Princeton, N.J. 1939. Google Scholar

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