Hostname: page-component-cd9895bd7-gxg78 Total loading time: 0 Render date: 2024-12-26T07:22:48.745Z Has data issue: false hasContentIssue false

Unipotent differential algebraic groups as parameterized differential Galois groups

Published online by Cambridge University Press:  18 July 2013

Andrey Minchenko
Affiliation:
The Hebrew University of Jerusalem, Einstein Institute of Mathematics, Jerusalem, 91904, Israel (an.minchenko@gmail.com)
Alexey Ovchinnikov
Affiliation:
CUNY Queens College, Department of Mathematics, 65-30 Kissena Blvd, Queens, NY 11367, USA CUNY Graduate Center, Department of Mathematics, 365 Fifth Avenue, NY 10016, USA (aovchinnikov@qc.cuny.edu)
Michael F. Singer
Affiliation:
North Carolina State University, Department of Mathematics, Raleigh, NC 27695-8205, USA (singer@ncsu.edu)

Abstract

We deal with aspects of direct and inverse problems in parameterized Picard–Vessiot (PPV) theory. It is known that, for certain fields, a linear differential algebraic group (LDAG) $G$ is a PPV Galois group over these fields if and only if $G$ contains a Kolchin-dense finitely generated group. We show that, for a class of LDAGs $G$, including unipotent groups, $G$ is such a group if and only if it has differential type $0$. We give a procedure to determine if a parameterized linear differential equation has a PPV Galois group in this class and show how one can calculate the PPV Galois group of a parameterized linear differential equation if its Galois group has differential type $0$.

Type
Research Article
Copyright
©Cambridge University Press 2013 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Arreche, C., Computing the differential Galois group of a one-parameter family of second order linear differential equations, (2012), (URL http://arxiv.org/abs/1208.2226).Google Scholar
Cassidy, P., Differential algebraic groups, Amer. J. Math. 94 (1972), 891954(URL http://www.jstor.org/stable/2373764).Google Scholar
Cassidy, P., The differential rational representation algebra on a linear differential algebraic group, J. Algebra 37 (2) (1975), 223238(URL http://dx.doi.org/10.1016/0021-8693(75)90075-7).CrossRefGoogle Scholar
Cassidy, P., Unipotent differential algebraic groups, in Contributions to algebra: Collection of papers dedicated to Ellis Kolchin, pp. 83115 (Academic Press, 1977).CrossRefGoogle Scholar
Cassidy, P., The classification of the semisimple differential algebraic groups and linear semisimple differential algebraic Lie algebras, J. Algebra 121 (1) (1989), 169238(URL http://dx.doi.org/10.1016/0021-8693(89)90092-6).Google Scholar
Cassidy, P. and Singer, M., Galois theory of parametrized differential equations and linear differential algebraic group, IRMA Lect. Math. Theoret. Phys. 9 (2007), 113157 (URL http://dx.doi.org/10.4171/020-1/7).CrossRefGoogle Scholar
Compoint, E. and Singer, M., Computing Galois groups of completely reducible differential equations, J. Symbolic Comput. 28 (4–5) (1999), 473494(URL http://dx.doi.org/10.1006/jsco.1999.0311).CrossRefGoogle Scholar
Curtis, C. W. and Reiner, I., Representation theory of finite groups and associative algebras. (AMS Chelsea Publishing, Providence, RI, 2006), (reprint of the 1962 original).CrossRefGoogle Scholar
Deligne, P. and Milne, J., Tannakian categories, in Hodge cycles, motives, and Shimura varieties, Lecture Notes in Mathematics, Volume 900, pp. 101228 (Springer-Verlag, Berlin, 1981), (URL http://dx.doi.org/10.1007/978-3-540-38955-2_4).Google Scholar
Dreyfus, T., Computing the Galois group of some parameterized linear differential equation of order two, Proceedings of the American Mathematical Society (2012), in press, URL http://arxiv.org/abs/1110.1053.Google Scholar
Dreyfus, T., A density theorem for parameterized differential Galois theory, (2012), (URL http://arxiv.org/abs/1203.2904).Google Scholar
Gillet, H., Gorchinskiy, S. and Ovchinnikov, A., Parameterized Picard–Vessiot extensions and Atiyah extensions, Adv. Math. 238 (2013), 322411(URL http://dx.doi.org/10.1016/j.aim.2013.02.006).CrossRefGoogle Scholar
Gorchinskiy, S. and Ovchinnikov, A., Isomonodromic differential equations and differential categories, (2012), (URL http://arxiv.org/abs/1202.0927).Google Scholar
Grigoriev, D. Y., Complexity for irreducibility testing for a system of linear ordinary differential equations, in Proceedings of the international symposium on symbolic and algebraic computation- ISSAC’90 (ed. Nagata, M. and Watanabe, S.). pp. 225230 (ACM Press, 1990), (URL http://dx.doi.org/10.1145/96877.96932).Google Scholar
Grigoriev, D. Y., Complexity of factoring and calculating the gcd of linear ordinary differential operators, J. Symbolic Comput. 10 (1) (1990), 738(URL http://dx.doi.org/10.1016/S0747-7171(08)80034-X).CrossRefGoogle Scholar
Hardouin, C. and Singer, M., Differential Galois theory of linear difference equations, Math. Ann. 342 (2) (2008), 333377(URL http://dx.doi.org/10.1007/s00208-008-0238-z).Google Scholar
Hrushovski, E., Computing the Galois group of a linear differential equation, Banach Center Publ. 58 (2002), 97138 (URL http://dx.doi.org/10.4064/bc58-0-9).Google Scholar
Kamensky, M., Tannakian formalism over fields with operators, Int. Math. Res. Not. 361 (2012), 163171 (URL http://dx.doi.org/10.1093/imrn/rns190).Google Scholar
Kamensky, M., Model theory and the Tannakian formalism, Trans. Amer. Math. Soc. (2013), in press, (URL http://arxiv.org/abs/0908.0604).Google Scholar
Kaplansky, I., An introduction to differential algebra. (1957).Google Scholar
Kolchin, E., Algebraic matric groups and the Picard–Vessiot theory of homogeneous linear ordinary differential equations, Ann. of Math. (2) 49 (1) (1948), 142(URL http://www.jstor.org/stable/1969111).Google Scholar
Kolchin, E. R., Algebraic groups and algebraic dependence, Amer. J. Math. 90 (1968), 11511164 (URL http://www.jstor.org/stable/2373294).CrossRefGoogle Scholar
Kolchin, E., Differential algebra and algebraic groups. (Academic Press, New York, 1973).Google Scholar
Kolchin, E., Differential algebraic groups. (Academic Press, New York, 1985).Google Scholar
Landesman, P., Generalized differential Galois theory, Trans. Amer. Math. Soc. 360 (8) (2008), 44414495 (URL http://dx.doi.org/10.1090/S0002-9947-08-04586-8).Google Scholar
Manin, J. I., Algebraic curves over fields with differentiation, Izv. Akad. Nauk SSSR. Ser. Mat. 22 (1958), 737756 An English translation appears in Transl. Amer. Math. Soc., Ser., Series 2, Twenty-two papers on algebra, number theory and differential geometry 37 (1964) pp. 59–78.Google Scholar
Minchenko, A. and Ovchinnikov, A., Zariski closures of reductive linear differential algebraic groups, Adv. Math. 227 (3) (2011), 11951224(URL http://dx.doi.org/10.1016/j.aim.2011.03.002).Google Scholar
Minchenko, A., Ovchinnikov, A. and Singer, M., Reductive linear differential algebraic groups and the Galois groups of parameterized linear differential equations, (2013), (URL http://arxiv.org/abs/1304.2693).Google Scholar
Mitschi, C. and Singer, M., Monodromy groups of parameterized linear differential equations with regular singularities, Bull. Lond. Math. Soc. 44 (5) (2012), 913930 (URL http://dx.doi.org/10.1112/blms/bds021).CrossRefGoogle Scholar
Ovchinnikov, A., Tannakian approach to linear differential algebraic groups, Transform. Groups 13 (2) (2008), 413446(URL http://dx.doi.org/10.1007/s00031-008-9010-4).Google Scholar
Ovchinnikov, A., Tannakian categories, linear differential algebraic groups, and parametrized linear differential equations, Transform. Groups 14 (1) (2009), 195223 (URL http://dx.doi.org/10.1007/s00031-008-9042-9).Google Scholar
van der Put, M. and Singer, M., Galois theory of linear differential equations. (Springer, Berlin, 2003), (URL http://dx.doi.org/10.1007/978-3-642-55750-7).Google Scholar
Singer, M., Linear algebraic groups as parameterized Picard–Vessiot Galois groups, J. Algebra 373 (1) (2013), 153161(URL http://dx.doi.org/10.1016/j.jalgebra.2012.09.037).Google Scholar
Springer, T. A., Linear algebraic groups, second edn., Progress in Mathematics, Volume 9 (Birkhäuser Boston Inc,, Boston, MA, 1998), (URL http://dx.doi.org/10.1007/978-0-8176-4840-4).Google Scholar
Tretkoff, C. and Tretkoff, M., Solution of the inverse problem in differential Galois theory in the classical case, Amer. J. Math. 101 (1979), 13271332(URL http://www.jstor.org/stable/2374143).Google Scholar
Trushin, D., Splitting fields and general differential Galois theory, Sbornik: Mathematics 201 (9) (2010), 13231353(URL http://dx.doi.org/10.1070/SM2010v201n09ABEH004114).Google Scholar
Waterhouse, W., Introduction to affine group schemes. (Springer, Berlin, 1979), (URL http://dx.doi.org/10.1007/978-1-4612-6217-6).CrossRefGoogle Scholar
Wibmer, M., Existence of $\partial $-parameterized Picard–Vessiot extensions over fields with algebraically closed constants, J. Algebra 361 (2012), 163171(URL http://dx.doi.org/10.1016/j.jalgebra.2012.03.035).Google Scholar