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POLYNOMIAL ENDOMORPHISMS PRESERVING OUTER RANK IN TWO VARIABLES

Published online by Cambridge University Press:  16 February 2012

YONG JIN
Affiliation:
School of Mathematics, Jilin University, 130012 Changchun, PR China (email: [email protected])
XIANKUN DU*
Affiliation:
School of Mathematics, Jilin University, 130012 Changchun, PR China (email: [email protected])
*
For correspondence; e-mail: [email protected]
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Abstract

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An endomorphism φ of a polynomial ring is said to preserve outer rank if φ sends each polynomial to one with the same outer rank. For the polynomial ring in two variables over a field of characteristic 0 we prove that an endomorphism φ preserving outer rank is an automorphism if one of the following conditions holds: (1) the Jacobian of φ is a nonzero constant; (2) the image of φ contains a coordinate; (3) φ has a ‘fixed point’.

Type
Research Article
Copyright
Copyright © Australian Mathematical Publishing Association Inc. 2012

Footnotes

Supported by NSF of China (No.11071097) and ‘211 Project’ and ‘985 Project’ of Jilin University.

References

[1]Bergman, G. M., ‘Supports of derivations, free factorizations, and ranks of fixed subgroups in free groups’, Trans. Amer. Math. Soc. 351 (1999), 15311550.CrossRefGoogle Scholar
[2]Campbell, L. A. and Yu, J.-T., ‘Two dimensional coordinate polynomials and dominant maps’, Comm. Algebra 28 (2000), 22972301.CrossRefGoogle Scholar
[3]Costa, D. L., ‘Retracts of polynomial algebras’, J. Algebra 44 (1977), 492502.CrossRefGoogle Scholar
[4]Drensky, V. and Yu, J.-T., ‘Test polynomials for automorphisms of polynomial and free associative algebras’, J. Algebra 207 (1998), 491510.CrossRefGoogle Scholar
[5]van den Essen, A. and Shpilrain, V., ‘Some combinatorial questions about polynomial maps’, J. Pure Appl. Algebra 119 (1997), 4752.CrossRefGoogle Scholar
[6]Gong, S.-J. and Yu, J.-T., ‘The linear coordinate preserving problem’, Comm. Algebra 36 (2008), 13541364.CrossRefGoogle Scholar
[7]Gong, S.-J. and Yu, J.-T., ‘Test elements, retracts and automorphic orbits’, J. Algebra 320 (2008), 30623068.CrossRefGoogle Scholar
[8]Jelonek, Z., ‘A solution of the problem of van den Essen and Shpilrian’, J. Pure Appl. Algebra 137 (1999), 4955.CrossRefGoogle Scholar
[9]Jelonek, Z., ‘Test polynomials’, J. Pure Appl. Algebra 147 (2000), 125132.CrossRefGoogle Scholar
[10]Lyndon, R. and Schupp, P., Combinatorial Group Theory. Reprint of the 1977 edition, Classics in Mathematics (Springer, Berlin, 2001).Google Scholar
[11]McKay, J. H. and Wang, S. S. S., ‘An inversion formula for two polynomials in two variables’, J. Pure Appl. Algebra 40 (1986), 245257.CrossRefGoogle Scholar
[12]Mikhalev, A. A. and Zolotykh, A. A., ‘The rank of an element of the free color Lie (p-) superalgebra’, Dokl. Akad. Nauk 334 (1994), 690693; English translation: Russian Acad. Sci. Dokl. Math. 49 (1994)(1), 189–193.Google Scholar
[13]Shpilrain, V. and Yu, J.-T., ‘Polynomial retracts and the Jacobian conjecture’, Trans. Amer. Math. Soc. 352 (2000), 477484.CrossRefGoogle Scholar
[14]Shpilrain, V. and Yu, J.-T., ‘Test polynomials, retracts, and the Jacobian conjecture’, in: Affine Algebraic Geometry, Contemporary Mathematics, 369 (American Mathematical Society, Providence, RI, 2005), pp. 253259.CrossRefGoogle Scholar
[15]Umirbaev, U. U., ‘On ranks of elements of free groups’, Fundam. Prikl. Mat. 2 (1996), 313315.Google Scholar
[16]Yang, Q., ‘Retracts, test elements and automorphic orbit problem for polynomial algebras’. Master’s Thesis, Jilin University, China, 2010.Google Scholar
[17]Yu, J.-T., ‘Automorphic orbit problem for polynomial algebras’, J. Algebra 319 (2008), 966970.CrossRefGoogle Scholar