Browsing 2008 by MFO Scientific Program "OWLF 2007"

Now showing items 1-3 of 3

    • A Characterization of Semisimple Plane Polynomial Automorphisms 

      [OWP-2008-08] Maubach, Stefan; Furter, Jean-Philippe (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-12)
      It is well-known that an element of the linear group $GL_n(\mathbb{C})$ is semisimple if and only if its conjugacy class is Zariski closed. The aim of this paper is to show that the same result holds for the group of complex ...

    • The Nagata automorphism is shifted linearizable 

      [OWP-2008-09] Maubach, Stefan; Poloni, Pierre-Marie (Mathematisches Forschungsinstitut Oberwolfach, 2008-03-13)
      A polynomial automorphism $F$ is called shifted linearizable if there exists a linear map $L$ such that $LF$ is linearizable. We prove that the Nagata automorphism $N:= (X-Y\Delta-Z\Delta^2,Y+Z\Delta,Z)$ where $\Delta=XZ+Y^2$ ...

    • A note on k[z]-Automorphisms in Two Variables 

      [OWP-2008-17] Edo, Eric; Essen, Arno van den; Maubach, Stefan (Mathematisches Forschungsinstitut Oberwolfach, 2008)
      We prove that for a polynomial $f \in k[x, y, z]$ equivalent are: (1)$f$ is a $k[z]$-coordinate of $k[z][x,y]$, and (2) $k[x, y, z]/(f)\cong k^[2]$ and $f(x,y,a)$ is a coordinate in $k[x,y]$ for some $a \in k$. This solves ...