TY - JOUR TI - Notes on the decidability of addition and the Frobenius map for polynomials and rational functions AU - Chompitaki, Dimitra AU - Kamarianakis, Manos AU - Pheidas, Thanases TI - Notes on the decidability of addition and the Frobenius map for polynomials and rational functions AB - Let pbe a prime number, Fp a finite field with pelements, Fan algebraic extension of Fp and z a variable. We consider the structure of addition and the Frobenius map (i.e., x →xp) in the polynomial rings F[z] and in fields F(z) of rational functions. We prove that any question about F[z] in the structure of addition and Frobenius map may be effectively reduced to questions about the similar structure of the field F. Furthermore, we provide an example which shows that a fact which is true for addition and the Frobenius map in the polynomial rings F[z] fails to be true in F(z). As a consequence, certain methods used to prove model completeness for polynomials do not suffice to prove model completeness for similar structures for fields of rational functions F(z), a problem that remains open even for F= Fp. VL - 2022 IS - Number 57 PY - 2022 SN - 0137-2904 C1 - 2084-2589 SP - 53 EP - 60 DO - 10.4467/20842589RM.22.004.16661 UR - https://ejournals.eu/en/journal/reports-on-mathematical-logic/article/notes-on-the-decidability-of-addition-and-the-frobenius-map-for-polynomials-and-rational-functions KW - decidability KW - model completeness KW - Frobenius map KW - polynomial rings KW - rational functions