Effect of depolarization on the CHSH inequality: A hands-on approach

Quantum information theory provides a modern framework for understanding the behavior of quantum systems, especially in the presence of noise and environmental interactions. In this paper, we show how instructors can introduce the idea of quantum channels through a concrete application. We analyze the influence of depolarizing noise on the CHSH inequality in bipartite qubit systems. The depolarizing channel serves as a model to illustrate how decoherence affects non-classical correlations. Designed with upper-level undergraduate physics students in mind, our approach emphasizes intuitive understanding and computational transparency, making advanced topics in quantum information more approachable. By integrating foundational theory with calculations that can be performed by students, this work supports the integration of quantum information methods into contemporary physics education and offers a foundation for further student projects.