Causal fermion systems as a candidate for a unified physical theory

Felix Finster,Johannes Kleiner

doi:10.1088/1742-6596/626/1/012020

Felix Finster, Johannes Kleiner

Open Access

https://doi.org/10.1088/1742-6596/626/1/012020

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Abstract

The theory of causal fermion systems is an approach to describe fundamental physics. Giving quantum mechanics, general relativity and quantum field theory as limiting cases, it is a candidate for a unified physical theory. We here give a non-technical introduction.

Highlights

The theory of causal fermion systems has the same conceptual structure consisting of mathematical objects and a principle which singles out the physical configurations
Separable means that the Hilbert space has an at most countable orthonormal basis
It is important to note that each regularization gives rise to a different causal fermion system, describing a physical space-time with a different microstructure

Summary

Introduction

We have succeeded in constructing a causal fermion system starting from a system of Dirac wave functions in Minkowski space. The construction is guided by the usual structure of a Dirac wave function ψ, which to every space-time point x associates a spinor ψ(x). In the setting of causal fermion systems, for a space-time point x ∈ M we define the spin space Sx ⊂ H as the image of the operator x, Sx := x(H) .

Results

Conclusion