A general hidden variable model for the two-qubits system

TL;DR

This paper extends Bell's hidden variable model to arbitrary two-qubits states and observables, providing a more general and minimal hidden variable description with potential implications for quantum foundations.

Contribution

It introduces a generalized hidden variable model for two-qubits systems that encompasses arbitrary states and observables, including a minimal model with a single hidden variable.

Findings

Model applies to all two-qubits states and observables

Provides a minimal hidden variable description with one variable

Discusses implications for quantum theory and nonlocality

Abstract

We generalize Bell's hidden variable model describing the singlet state of a two-qubits system by extending it to arbitrary states and observables. As in the original work, we assume a uniform, state-independent probability distribution for the hidden variables which are identified with the unit vectors of a 3-dimensional real space. By slightly modifying our model, we provide also a minimal hidden variable description of the two-qubits system, relying on a single hidden variable. We discuss the main features and the implications of the model.