Testing Nonclassicality: The Status of Tomographic Completeness in Generalized Contextuality Experiments

This talk begins by explaining why generalized contextuality serves as the gold standard for identifying nonclassicality in a theory. We will review the concept and its advantages: it is grounded in a Leibnizian principle for theory evaluation, it is universally applicable, experimentally testable, and it encompasses many other notions of nonclassicality. Its universality, for instance, enables the assessment of nonclassicality in transformations. We will briefly illustrate how a linear program can witness contextuality in prepare-transform-measure experiments (https://arxiv.org/abs/2407.09624).

Next, we address a key experimental challenge in testing generalized contextuality: the assumption of tomographic completeness. In prepare-and-measure scenarios, this assumption holds that the available measurements can distinguish all relevant states, and vice versa. We will show why this assumption is central to contextuality tests, and how it can be relaxed: one can still assess nonclassicality using a relative tomographically complete set of procedures, as described in Ref.https://arxiv.org/abs/2409.13024. We conclude by discussing implications and future directions.

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This is a hybrid event:
Room D, the Institute of Physics PAS, Al. Lotników 32/46

Online: Zoom Link, (Passcode: 134595, Meeting ID: 823 8038 0442)

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