| | [No title] (Site not responding. Last check: 2007-10-09) |
 | | (2) The behavior of the integrand at infinity determines whether the expansion of the Green function is genuinely asymptotic in the literal, pointwise sense, or is merely valid in a distributional (Ces\`aro-averaged) sense; this is the difference between the heat kernel and the Schr\"odinger kernel. |
 | | In Section~\ref{sec5} we show that the moment asymptotic expansion, which is the basic building block in the asymptotic expansion of series and integrals,\cite{EK94} can be generalized to distributions, giving expansions that hold in an ``averaged'' or distributional sense explaining, for instance, the small-$t$ behavior of the Schr\"odinger propagator. |
 | | The expansion of $G(t)$ as $t \rightarrow 0^{+}$ will be a distributional or ``averaged'' expansion, in general, but when $g$ has the behavior of the elements of ${\cal K}$ at $\infty$ it becomes a pointwise expansion. |
| www.ma.utexas.edu /mp_arc/papers/97-551 (8980 words) |