Clarifying State Dependence in CHSH: Optimal Angular Configurations for the Four Bell States
Abstract
We identify and correct a common pedagogical omission in the presentation of the CHSH inequality. The angular configuration {0, π/2, π/4, -π/4}, historically optimal for the singlet state |Ψ⁻⟩, yields S=0 when incorrectly applied to other Bell states such as |Φ⁺⟩ using the standard CHSH form. We demonstrate that each Bell state requires specific angular configurations and reveal the duality between two canonical forms of CHSH. We provide a complete table of optimal configurations for all four Bell states, Python verification code, and specific educational protocols. This work, developed under the Kaelion Project v3.0, emphasizes that entanglement certification requires state-specific geometric alignment.
Fields of Study & Subjects
Quantum Mechanics and Applications
Quantum Information and Cryptography
Quantum Computing Algorithms and Architecture
Publication details
- Journal / source
- Zenodo (CERN European Organization for Nuclear Research)
- Publication date
- 9 January 2026
- Language
- EN
- Document type
- Preprint