# The Theory of Causal Fermion Systems

## Overview of Physical Aspects

## The Elementary Structures

Here you can find an introduction to the elementary structures of the theory and their basic properties.

### What is a Causal Fermion System?

Here you find an introduction to the basic mathematical structures that make up a Causal Fermion System.

### Motivation for F

On this page we give a motivation for the choice of the particular subspace of linear operators in the definition of a CFS.

## The Central Ideas of the Theory

### Causal Action Principle

The Causal Action Principle lies at the heart of the CFS theory.

### The Continuum Limit

The continuum limit is the workhorse behind the derivation of the well established theories.

### The Logic underlying the Derivation of the Classical Field Equations

As the derivation of physical laws in the CFS theory is different from most other theories, we dedicate this page to explain the logic at work.

## Main Results and Ontology

### The Standard Model and General Relativity

On this page we summarize the central physical results obtained so far in the theory of causal fermion systems.

### Quantum Field Theory

In a well-defined limiting case, causal fermion systems give rise to quantum field theory. We here summarize the present status and open problems.

### Why the Dirac Sea?

The original conception of the theory of causal fermion systems took the Dirac Sea as a starting point. Here we explain the motivation for this starting point.

### What is fundamental?

Here we address the question which concepts are fundamental and which are emergent phenomena.

### Underlying physical principles

Here we discuss which physical principles are built in or respected by theory of causal fermion systems.

## Phenomenology

### A Mechanism of Baryogenesis

The theory of causal fermion systems gives rise to a novel mechanism giving rise to a particle/anti-particle asymmetry and the creation of matter.

### A Mechanism for Dark Matter and Dark Energy

The theory of causal fermion systems gives a possible explanation for dark matter and dark energy.

## Wishlists and Relation to Other Theories

### Comments on Quantum Gravity Wishlists

On this page we present a collection of quantum gravity wishlists by various people and comment on what the CFS theory has to say about them.

### Relation to other Theories

Here we explore what sets CFS apart from other approaches to unification/quantum Gravity.