Abstract view
Higher Order Tangents to Analytic Varieties along Curves


Published:20030201
Printed: Feb 2003
Rüdiger W. Braun
Reinhold Meise
B. A. Taylor
Abstract
Let $V$ be an analytic variety in some open set in $\mathbb{C}^n$
which contains the origin and which is purely $k$dimensional. For a
curve $\gamma$ in $\mathbb{C}^n$, defined by a convergent Puiseux
series and satisfying $\gamma(0) = 0$, and $d \ge 1$, define $V_t :=
t^{d} \bigl( V\gamma(t) \bigr)$. Then the currents defined by $V_t$
converge to a limit current $T_{\gamma,d} [V]$ as $t$ tends to zero.
$T_{\gamma,d} [V]$ is either zero or its support is an algebraic
variety of pure dimension $k$ in $\mathbb{C}^n$. Properties of such
limit currents and examples are presented. These results will be
applied in a forthcoming paper to derive necessary conditions for
varieties satisfying the local Phragm\'enLindel\"of condition that
was used by H\"ormander to characterize the constant coefficient
partial differential operators which act surjectively on the space of
all real analytic functions on $\mathbb{R}^n$.