{ "id": "2401.07235", "version": "v1", "published": "2024-01-14T09:23:39.000Z", "updated": "2024-01-14T09:23:39.000Z", "title": "Dynamic Probability Logics: Axiomatization & Definability", "authors": [ "Somayeh Chopoghloo", "Massoud Pourmahdian" ], "categories": [ "math.LO" ], "abstract": "We first study probabilistic dynamical systems from logical perspective. To this purpose, we introduce the finitary dynamic probability logic} ($\\mathsf{DPL}$), as well as its infinitary extension $\\mathsf{DPL}_{\\omega_1}\\!$. Both these logics extend the (modal) probability logic ($\\mathsf{PL}$) by adding a temporal-like operator $\\bigcirc$ (denoted as dynamic operator) which describes the dynamic part of the system. We subsequently provide Hilbert-style axiomatizations for both $\\mathsf{DPL}$ and $\\mathsf{DPL}_{\\omega_1}\\!$. We show that while the proposed axiomatization for $\\mathsf{DPL}$ is strongly complete, the axiomatization for the infinitary counterpart supplies strong completeness for each countable fragment $\\mathbb{A}$ of $\\mathsf{DPL}_{\\omega_1}\\!$. Secondly, our research focuses on the (frame) definability of important properties of probabilistic dynamical systems such as measure-preserving, ergodicity and mixing within $\\mathsf{DPL}$ and $\\mathsf{DPL}_{\\omega_1}$. Furthermore, we consider the infinitary probability logic $\\mathsf{InPL}_{\\omega_1}$ (probability logic with initial probability distribution) by disregarding the dynamic operator. This logic studies {\\em Markov processes with initial distribution}, i.e. mathematical structures of the form $\\langle \\Omega, \\mathcal{A}, T, \\pi\\rangle$ where $\\langle \\Omega, \\mathcal{A}\\rangle$ is a measurable space, $T: \\Omega\\times \\mathcal{A}\\to [0, 1]$ is a Markov kernel and $\\pi: \\mathcal{A}\\to [0, 1]$ is a $\\sigma$-additive probability measure. We prove that many natural stochastic properties of Markov processes such as stationary, invariance, irreducibility and recurrence are $\\mathsf{InPL}_{\\omega_1}$-definable.", "revisions": [ { "version": "v1", "updated": "2024-01-14T09:23:39.000Z" } ], "analyses": { "keywords": [ "axiomatization", "definability", "infinitary counterpart supplies strong completeness", "markov processes", "finitary dynamic probability logic" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }