Abstract:
We investigates non-transitive temporal logic with the "tomorrow" operator. In this logic, the operator "necessary" $\Box$ coincides with the operator “possible” $\Diamond$ (or almost coincides in reflexive case). In addition to the basic properties of the reflexive non-transitive logic ${{\mathcal L}}^r$ (decidability, finite approximability), admissible rules of this logic are investigated. The main result consists in proving the structural completeness of this logic and its tabular extensions.
Keywords:modal logic, frame and model Kripke, admissible and globally admissible inference rule.
UDC:510.643; 517.11
Received: 29.04.2023 Received in revised form: 18.12.2023 Accepted: 26.02.2024