PIRSA:21090018

A quantum prediction as a collection of epistemically restricted classical predictions

APA

Braasch, W. (2021). A quantum prediction as a collection of epistemically restricted classical predictions. Perimeter Institute. https://pirsa.org/21090018

MLA

Braasch, William. A quantum prediction as a collection of epistemically restricted classical predictions. Perimeter Institute, Sep. 24, 2021, https://pirsa.org/21090018

BibTex

          @misc{ pirsa_21090018,
            doi = {10.48660/21090018},
            url = {https://pirsa.org/21090018},
            author = {Braasch, William},
            keywords = {Quantum Foundations},
            language = {en},
            title = { A quantum prediction as a collection of epistemically restricted classical predictions},
            publisher = {Perimeter Institute},
            year = {2021},
            month = {sep},
            note = {PIRSA:21090018 see, \url{https://pirsa.org}}
          }
          

William Braasch Dartmouth College

Abstract

A toy model due to Spekkens is constructed by applying an epistemic restriction to a classical theory but reproduces a host of phenomena that appear in quantum theory. The model advances the position that the quantum state may be interpreted as a reflection of an agent’s knowledge. However, the model fails to capture all quantum phenomena because it is non-contextual. Here we show how a theory similar to the one Spekkens proposes requires only a single augmentation to give quantum theory for certain systems. Specifically, one must combine all possible epistemically restricted classical accounts of a quantum experiment. The rule for combination is simple: sum the nonrandom parts of all classical predictions to arrive at the nonrandom part of the quantum prediction.