Abstract
A filling curve $\gamma$ on a based surface $S$ determines a pseudo-Anosov
homeomorphism $P(\gamma)$ of $S$ via the process of "point-pushing along
$\gamma$." We consider the relationship between the self-intersection number
$i(\gamma)$ of $\gamma$ and the dilatation of $P(\gamma)$; our main result is
that the dilatation is bounded between $(i(\gamma)+1)^1/5$ and
$9^i(\gamma)$. We also bound the least dilatation of any pseudo-Anosov in the
point-pushing subgroup of a closed surface and prove that this number tends to
infinity with genus. Lastly, we investigate the minimal entropy of any
pseudo-Anosov homeomorphism obtained by pushing along a curve with
self-intersection number $k$ and show that, for a closed surface, this number
grows like $łog(k)$.
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