arXiv subjects
Publications and source records attributed to Christoph Kesting.
We compare Fornasiero and Terzo's framework of generic derivations on algebraically bounded structures with Le\'on S\'anchez and Tressl's differentially large fields. We show in the case of a single derivation that genericity and differential largeness coincide for \'ez-fields, as introduced by Walsberg and Ye. We also show that an NTP$_2$ algebraically bounded structure remains NTP$_2$ after expanding by a generic derivation.
We prove relative quantifier elimination for Pal's multiplicative valued difference fields with an added lifting map of the residue field. Furthermore, we generalize a $\mathrm{NIP}$ transfer result for valued fields by Jahnke and Simon to $\mathrm{NTP}_2$ to show that said valued difference fields are $\mathrm{NTP}_2$ if and only if value group and residue field are.
James Freitag showed that the Klein j-function is not paffian over the complex numbers. We expand on this result by showing that a restriction of the Klein j-function to the imaginary interval (0, i) is not pfaffian over the real field exponential field in the sense of Miller and Speissegger.
We prove a dichotomy for o-minimal fields $\mathcal{R}$, expanded by a $T$-convex valuation ring (where $T$ is the theory of $\mathcal{R}$) and a compatible monomial group. We show that if $T$ is power bounded, then this expansion of $\mathcal{R}$ is model complete (assuming that $T$ is), it has a distal theory, and the definable sets are geometrically tame. On the other hand, if $\mathcal{R}$ defines an exponential function, then the natural numbers are externally definable in our expansion, precluding any sort of model theoretic tameness.