Patrick Speissegger
(Joint work with Tobias Kaiser) Recall from this post that not all germs in $\H$ have a holomorphic extension that maps definable real domains to definable real domains. In fact, the extension $\t_a$ of the translation $t_a$, for $a\gt 0$, does not even map real domains to real domains. So, in order to describe the…
(Joint work with Tobias Kaiser) The goal of this post is to introduce a rough measure of size for a real domain $U$, based on the level of its boundary function $f_U$. As before, “definable” means “definable in $\Ranexp$”. Let $\I$ be the set of all infinitely increasing $\,f \in \H$ and set $\bo:= \H_{\gt…
(Joint work with Tobias Kaiser) I introduce here the types of domains in $\LL$ used later to describe holomorphic extensions of one-variable functions definable in $\Ranexp$. In this post “definable” means “definable in $\Ranexp$”. DefinitionA set $U \subseteq \LL$ is a real domain if there exist $a \gt 0$ and a continuous function $f =…
(Joint work with Tobias Kaiser) We are interested in holomorphic extensions of one-variable functions definable in $\Ranexp$. Since $\exp$ and $\log$ are two crucial functions definable in $\Ranexp$, the natural domain on which to consider holomorphic extensions of all definable functions is the Riemann surface of the logarithm $$\LL:= (0,\infty) \times \RR$$ with its usual…
(Joint work with Tobias Kaiser) The goal of this post is to describe the Hardy field $\H = \Hanexp$ of the expansion $\Ranexp$ of the real field by all restricted analytic functions and the exponential function, based on van den Dries, Macintyre and Marker’s papers on $\Ranexp$ and on LE-series. In particular, the first paper…