[Todos CMAT] Nueva actividad del Workshop: Charla de Teresa Krick

[Diego Armentano]

Hola a todos.
Esta tarde a las 16:00hs Teresa Krick va  a dar una charla en el marco del
Workshop en Complejidad, el cual se esta desarrollando en el piso 14 del
CMAT.
Saludos,
  Diego

Título:

   *On arithmetic effective Nullstellensätze and **implicitization problems*

Abstract:

Joint work  with Carlos D'Andrea and Martin Sombra, on precise bounds for
the effective Nullstellensatz and the implicitation problem  in their
arithmetic aspects.

The Nullstellensatz establishes that if f_1,...,f_s in k[x_1,...,x_n] are
polynomials with no common roots in the algebraic closure of the field k,
then they satisfy a Bezout identity 1=g_1f_1+...+g_sf_s for some polynomials
g_1,...,g_s in k[x_1,...,x_n].

The implicitization problem consists in computing equations for an
algebraic variety from a given rational parameterization of it. The typical
case is when the variey is a hypersurface, in which case it is defined by a
single ``implicit equation'' and the problem
consists in computing  it.

I will discuss degree and height bounds for these problems for the cases
when the polynomials are defined over the rational numbers or over a field
of rational functions, which we obtain by studying
heights of varieties in multiprojective spaces.



_______________________________________________
Todos-dm mailing list
Todos-dm en dm.uba.ar
http://mail.dm.uba.ar/mailman/listinfo/todos-dm
------------ próxima parte ------------
Se ha borrado un adjunto en formato HTML...
URL: <http://www.cmat.edu.uy/pipermail/todos/attachments/20110412/064b2133/attachment.html>