Valued difference fields and NTP2
Résumé
We show that the theory of the non-standard Frobenius automorphism, acting on an algebraically closed valued field of equal characteristic 0, is NTP2. More generally, we prove that a contractive sigma-henselian valued difference field of characteristic 0 is NTP2, provided both the residue difference field and the value group (as an ordered difference group) are NTP2. In addition, we demonstrate an analogous result for a possible refinement of NTP2 called resilience.