Causal Fermion Systems as a Candidate for a Unified Physical Theory

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.Comment: 19 pages, LaTeX, minor improvements (published version

Noether-Like Theorems for Causal Variational Principles

The connection between symmetries and conservation laws as made by Noether's theorem is extended to the context of causal variational principles and causal fermion systems. Different notions of continuous symmetries are introduced. It is proven that these symmetries give rise to corresponding conserved quantities, expressed in terms of so-called surface layer integrals. In a suitable limiting case, the Noether-like theorems for causal fermion systems reproduce charge conservation and the conservation of energy and momentum in Minkowski space. Thus the conservation of charge and energy-momentum are found to be special cases of general conservation laws which are intrinsic to causal fermion systems.Comment: 41 pages, LaTeX, 3 figures, small improvements (published version

If consciousness is dynamically relevant, artificial intelligence isn't conscious

We demonstrate that if consciousness is relevant for the temporal evolution of a system's states -- that is, if it is dynamically relevant -- then AI systems cannot be conscious. That is because AI systems run on CPUs, GPUs, TPUs or other processors which have been designed and verified to adhere to computational dynamics that systematically preclude or suppress deviations. The design and verification preclude or suppress, in particular, potential consciousness-related dynamical effects, so that if consciousness is dynamically relevant, AI systems cannot be conscious

Dynamics of Causal Fermion Systems - Field Equations and Correction Terms for a New Unified Physical Theory

The theory of causal fermion systems is a new physical theory which aims to describe a fundamental level of physical reality. Its mathematical core is the causal action principle. In this thesis, we develop a formalism which connects the causal action principle to a suitable notion of fields on space-time. We derive field equations from the causal action principle and find that the dynamics induced by the field equations conserve a symplectic form which gives rise to an Hamiltonian time evolution if the causal fermion system admits a notion of 'time'. In this way, we establish the dynamics of causal fermion systems. Remarkably, the causal action principle implies that there are correction terms to the field equations, which we subsequently derive and study. In particular, we prove that there is a stochastic and a non-linear correction term and investigate how they relate to the Hamiltonian time evolution. Furthermore, we give theorems which generalize the connection between symmetries and conservation laws in Noether's theorems to the theory of causal fermion systems. The appearance of the particular correction terms is reminiscent of dynamical collapse models in quantum theory

Consciousness Requires Mortal Computation

All organisms compute, though in vastly different ways. Whereas biological systems carry out mortal computation, contemporary AI systems and all previous general purpose computers carry out immortal computation. Here, we show that if Computational Functionalism holds true, consciousness requires mortal computation. This implies that none of the contemporary AI systems, and no AI system that runs on hardware of the type in use today, can be conscious