Local Inaccessibility of Random Classical Information and Their Implications in the Change Point Problem

Snehasish Roy Chowdhury; Subhendu B. Ghosh; Tathagata Gupta; Anandamay Das Bhowmik; Sutapa Saha; Some Sankar Bhattacharya; Tamal Guha

arXiv · 2307.08457

Local Inaccessibility of Random Classical Information and Their Implications in the Change Point Problem

Snehasish Roy Chowdhury·Subhendu B. Ghosh·Tathagata Gupta·Anandamay Das Bhowmik·Sutapa Saha·Some Sankar Bhattacharya·Tamal Guha

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Abstract

Discrimination of quantum states under local operations and classical communication (LOCC) is an intriguing question in the context of local retrieval of classical information, encoded in the multipartite quantum systems. All the local quantum state discrimination premises, considered so far, mimic a basic communication set-up, where the spatially separated decoding devices are independent of any additional input. Here, exploring a generalized communication scenario, we introduce a framework for input-dependent local quantum state discrimination, which we call local random authentication (LRA). We report that impossibility of LRA certifies the presence of entangled states in the ensemble, a feature absent from erstwhile nonlocality arguments based on local state discrimination. Additionally, we explore the salient features of this state discrimination prototype for arbitrary set of orthogonal quantum states and compare them with the traditional notion of local quantum state discrimination. Finally, our results reveal a fundamental information-theoretic implications in the local estimation of quantum change point problems.

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Snehasish Roy Chowdhury, Subhendu B. Ghosh, Tathagata Gupta, Anandamay Das Bhowmik, Sutapa Saha, Some Sankar Bhattacharya, Tamal Guha. 2023-07-17. Local Inaccessibility of Random Classical Information and Their Implications in the Change Point Problem. https://arxiv.org/abs/2307.08457

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