Hostname: page-component-cd9895bd7-lnqnp Total loading time: 0 Render date: 2024-12-27T09:00:42.412Z Has data issue: false hasContentIssue false

Invariant theory for linear differential systems modeled after the grassmannian Gr(n, 2n)

Published online by Cambridge University Press:  22 January 2016

Takeshi Sasaki
Affiliation:
Department of Mathematics, Kobe University, Kobe, 657-8501, Japan
Masaaki Yoshida
Affiliation:
Department of Mathematics, Kyushu University, Fukuoka, 812-8581, Japan
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

We find invariants for the differential systems of rank 2n in n2 variables with n unknowns under the linear changes of the unknowns with variable coefficients. We look for a set of coefficients that determines the other coefficients, and give transformation rules under the linear changes above and coordinate changes. These can be considered as a generalization of the Schwarzian derivative, which is the invariant for second order ordinary differential equations under the change of the unknown by multiplying a non-zero function. Special treatment is done when n = 2: the conformal structure obtained through the Plücker embedding is studied, and a relation with line congruences is discussed.

Keywords

Type
Research Article
Copyright
Copyright © Editorial Board of Nagoya Mathematical Journal 2003

References

[1] Matsumoto, K., Sasaki, T. and Yoshida, M., The monodromy of the period map of a 4-parameter family of K3 surfaces and the hypergeometric function of type (3, 6), Intern. J. of Math., 3 (1992), 1164.Google Scholar
[2] Sasaki, T., Projective Differential Geometry and Linear Homogeneous Differential Equations, Rokko Lectures in Math. 5, Kobe Univ, 1999.Google Scholar
[3] Sasaki, T. and Yoshida, M., Linear differential equations modeled after hyperquadrics, Tôhoku Math. J., 41 (1989), 321348.CrossRefGoogle Scholar
[4] Wilczynski, E. J., Projective Differential Geometry of Curves and Ruled Surfaces, Teubner, 1906.Google Scholar
[5] Yoshida, M., Fuchsian Differential Equations, Vieweg Verlag, 1987.Google Scholar