Quantum causal models via QBism: the short version

Abstract

This paper is a concise summary of the main ideas presented in the companion paper `Quantum causal models via Quantum Bayesianism'[arXiv:1806.00895]. I present the proposed definition of a quantum causal model with minimal background and justification, focusing only on its essential physical properties. The mathematical structure and definitions are provided as an Appendix. I discuss the possible physical significance of the fact that the model is symmetric under causal inversion.