Toward a factually induced space-time quantum logic

A. R. Marlow

Carl H. Brans

Alejandro Ascarate

Based on a clear ontology of material individuals, we analyze in detail the factual semantics of quantum theory, and argue that the basic mathematical formalism of quantum theory is just okay with (a certain form of ) realism and that it is perfectly applicable to quantum gravity. This is basically a process about 'cleansing' the formalism from semantic assumptions and physical referents that it doesn't really need (we use the term 'semantics' in the sense of the factual semantics of a physical theory, and not in the sense of model theory of abstract mathematics or logic). We base our study on the usual non-Boolean lattice of projectors in a Hilbert space and probability measures on it, to which we give a careful physical interpretation using the mentioned tools in order to avoid the usual problems posed by this task. At the end, we study a possible connection with the theory of quantum duration and time proposed in [arXiv:2012.03994, arXiv:2107.06693], for which this paper serves as a philosophical basis, and argue for our view that quantum gravity may show that what we perceive as change in the classical world was just (an ontologically fundamental) quantum collapse all along.

Alejandro Andrés Hnilo

Quantum non-locality has become a popular term. Yet, its precise meaning, and even its mere existence, is the subject of controversies. The main cause of the controversies is the never ending discussion on the appropriate definitions of Locality and Realism in the derivation of Bell's inequalities. On the other hand, Louis Sica derived Bell's inequalities from the hypothesis that time series of outcomes observed in one station do not change if the setting in the other (distant) station is changed. The derivation is based on arithmetical properties of time series only; it does not involve the definitions of Locality, Realism and probabilities, and is valid for series of any length. An important consequence is that violation of Bell's inequalities implies the series recorded (at the same time) in one station to be different if the setting in the other station is changed. This result gives precise meaning to the idea of quantum non-locality, and also makes evident why using it for faster than light signaling is impossible (because the difference is between factual and counter-factual series). Finally, it is demonstrated that series of outcomes, even if they violate Bell's inequalities, can be always embedded in a set of factual and counter-factual data that does hold to Bell's inequalities. Loosely speaking, the factual world may be quantum or not, but the union of factual and counter-factual worlds is always classical.

Gian‐Carlo Rota

A large body of mathematics consists of facts that can be presented and described much like any other natural phenomenon. These facts, at times explicitly brought out as theorems, at other times concealed within a proof, make up most of the applications of mathematics, and are the most likely to survive changes of style and of interest. This ENCYCLOPEDIA will attempt to present the factual body of all mathematics. Clarity of exposition, accessibility to the non-specialist, and a thorough bibliography are required of each author. Volumes will appear in no particular order, but will be organized into sections, each one comprising a recognizable branch of present-day mathematics. Numbers of volumes and sections will be reconsidered as times and needs change. It is hoped that this enterprise will make mathematics more widely used where it is needed, and more accessible in fields in which it can be applied but where it has not yet penetrated because of insufficient information. The present volume is meant to be the first of a series on quantum mechanics and its applications. It deals with the foundations as well as the fascinating logic of quantum mechanics. This volume is more general and at places less factual than other volumes of the ENCYCLOPEDIA; nevertheless the thorough presentation will guide the reader to gain an overview of a theory that, together with relativity, is regarded as the greatest achievement in physics in this century.

Dov M. Gabbay, Kurt Engesser, Daniel J. Lehmann