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Related papers: Causal Fermion Systems and Octonions

200 papers

It is shown that the theory of causal fermion systems gives rise to a novel mechanism for dark matter and dark energy. This mechanism is first worked out for cubical subsets of Minkowski space with periodic boundary conditions. Then it is…

General Relativity and Quantum Cosmology · Physics 2023-03-17 Felix Finster , J. M. Isidro

In this paper, we argue that spacetime in causal fermion systems can be understood as the web of correlations of a many-body quantum system.This argument highlights the fact that causal fermion systems is a completely relational theory. We…

Mathematical Physics · Physics 2025-04-29 Patrick Fischer , Claudio F. Paganini

The octonions are one of the four normed division algebras, together with the real, complex and quaternion number systems. The latter three hold a primary place in random matrix theory, where in applications to quantum physics they are…

Mathematical Physics · Physics 2017-06-21 Peter J. Forrester

After reviewing the theory of "causal fermion systems" (CFS theory) and the "Events, Trees, and Histories Approach" to quantum theory (ETH approach), we compare some of the mathematical structures underlying these two general frameworks and…

Mathematical Physics · Physics 2021-03-08 Felix Finster , Jürg Fröhlich , Marco Oppio , Claudio F. Paganini

The structure of octonionic bimodules is formulated in this paper. It turns out that every octonionic bimodule is a tensor product, the category of octonionic bimodules is isomorphic to the category of real vector spaces. We show that there…

Rings and Algebras · Mathematics 2020-07-13 Qinghai Huo , Guangbin Ren

In this paper, we consider fermionic systems in discrete spacetime evolving with a strict notion of causality, meaning they evolve unitarily and with a bounded propagation speed. First, we show that the evolution of these systems has a…

Quantum Physics · Physics 2014-01-08 Terence C. Farrelly , Anthony J. Short

In the case of systems composed of identical particles, a typical instance in quantum statistical mechanics, the standard approach to separability and entanglement ought to be reformulated and rephrased in terms of correlations between…

Quantum Physics · Physics 2014-05-21 F. Benatti , R. Floreanini

The aim of this paper is to provide a largely self-contained, compact and comprehensible introduction to the basic ideas behind correlation geometry, which underlies the theory of causal fermion system (CFS). A key focus here is on the…

Mathematical Physics · Physics 2026-04-21 Claudio F. Paganini

Fermion systems in discrete space-time are introduced as a model for physics on the Planck scale. We set up a variational principle which describes a non-local interaction of all fermions. This variational principle is symmetric under…

High Energy Physics - Theory · Physics 2007-10-27 Felix Finster

It is shown that, in the non-relativistic limit, causal fermion systems give rise to an effective collapse theory. The nonlinear and stochastic correction terms to the Schr\"odinger equation are derived from the causal action principle. The…

Mathematical Physics · Physics 2024-09-12 Felix Finster , Johannes Kleiner , Claudio F. Paganini

There must exist a reformulation of quantum field theory, even at low energies, which does not depend on classical time. The octonionic theory proposes such a reformulation, leading to a pre-quantum pre-spacetime theory. The ingredients for…

General Physics · Physics 2023-09-01 Tejinder P. Singh

Causal variational principles, which are the analytic core of the physical theory of causal fermion systems, are found to have an underlying Hamiltonian structure, giving a formulation of the dynamics in terms of physical fields in…

Mathematical Physics · Physics 2017-10-17 Felix Finster , Johannes Kleiner

In real-life statistical data, it seems that conditional probabilities for the effect given their causes tend to be less complex and smoother than conditionals for causes, given their effects. We have recently proposed and tested methods…

Statistical Mechanics · Physics 2009-01-30 Dominik Janzing

Can the direction of time and the causal structure of space-time be inferred from operational principles? Causal models and tensor networks offer complementary perspectives: the former encodes cause-effect relations via directed graphs,…

Quantum Physics · Physics 2026-03-16 Carla Ferradini , Giulia Mazzola , V. Vilasini

Causal fermion systems and Riemannian fermion systems are proposed as a framework for describing non-smooth geometries. In particular, this framework provides a setting for spinors on singular spaces. The underlying topological structures…

Mathematical Physics · Physics 2019-05-06 Felix Finster , Niky Kamran

Understanding the causal influences that hold among parts of a system is critical both to explaining that system's natural behaviour and to controlling it through targeted interventions. In a quantum world, understanding causal relations is…

Quantum Physics · Physics 2018-01-22 Jean-Philippe W. MacLean , Katja Ried , Robert W. Spekkens , Kevin J. Resch

Causal fermion systems incorporate local gauge symmetry in the sense that the Lagrangian and all inherent structures are invariant under local phase transformations of the physical wave functions. In the present paper it is explained and…

Mathematical Physics · Physics 2020-08-10 Felix Finster , Sebastian Kindermann

We construct the causal fermion system for globally hyperbolic spacetimes starting in the framework of algebraic quantum field theory. The fermionic projector is identified with the one-particle density operator of a quasi-free Hadamard…

Mathematical Physics · Physics 2026-05-29 Patrick Fischer , Felix Finster

In fundamental theories that accounts for quantum gravitational effects, the spacetime causal structure is expected to be quantum uncertain. Previous studies of quantum causal structure focused on finite-dimensional systems. Here we present…

Quantum Physics · Physics 2019-02-18 Ding Jia

A symmetric monoidal category naturally arises as the mathematical structure that organizes physical systems, processes, and composition thereof, both sequentially and in parallel. This structure admits a purely graphical calculus. This…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Bob Coecke , Raymond Lal