Logic and Philosophy of Time

Vol. 7 No. 1 (2026): Logic and Philosophy of Time
Articles

Modeling Radical Indeterminacy in Branching Time Semantics

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Ciro de Florio
Università Cattolic
Aldo Frigerio
Università Cattolica
Filippo Mancini
University of Eastern Piedmont
DOI: https://doi.org/10.54337/lpt.v7i1.10812

Published 07-02-2026

Keywords

  • Radical Indeterminacy,
  • Branching Time Semantics,
  • Doomsday,
  • End of Time

How to Cite

de Florio, C., Frigerio, A., & Mancini, F. (2026). Modeling Radical Indeterminacy in Branching Time Semantics. Logic and Philosophy of Time, 7(1), 1–20. https://doi.org/10.54337/lpt.v7i1.10812

Copyright (c) 2026 Logic and Philosophy of Time

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Abstract

With the primary aim of preserving indeterminism and keeping the future open, several different branching time semantics have been proposed. The temporal frames on which these semantics are based are trees whose branches are typically endless. However, it is a genuine metaphysical possibility that the series of
moments might come to an end. In light of this, a radical notion of indeterminacy can be adopted, one that is formally captured not merely by the branching of the future, but by a tree-like structure of time that, in addition to unbounded branches, also includes branches that terminate (dead branches). In this article, (i) we show how such a temporal frame can be formally developed, (ii) examine some implications of incorporating dead branches for both Peircean and Ockhamist branching time semantics, and (iii) outline a new semantics tailored to this kind of trees.

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