No-masking theorem for observables

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Bhowmick, Swapnil, Srivastav, Abhay, Pati, Arun Kumar
Natura: Preprint
Pubblicazione: 2022
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866910567039500288
author Bhowmick, Swapnil
Srivastav, Abhay
Pati, Arun Kumar
author_facet Bhowmick, Swapnil
Srivastav, Abhay
Pati, Arun Kumar
contents The no-masking theorem for quantum information proves that it is impossible to encode an arbitrary input state into a larger bipartite entangled state such that the full information is stored in the correlation but the individual subsystems have no information about the input state. Here, we ask the question: Is it possible to mask an observable such that the information about the observable is available in the joint system, but individual subsystems reveal nothing about the imprints of the observable? This generalizes the notion of masking to observables. We show that a universal unitary that can mask an arbitrary observable in any dimension does not exist. For a qubit system, we show that the masking operation for a given observable is locally unitarily connected to the SWAP operation. This suggests a conservation law for information content of observables that goes beyond the conservation laws under symmetry operations. Furthermore, we prove that the unconditional no-bit commitment result follows from the no-masking theorem for observables. Our results can have important applications in quantum information and quantum communication where we encode information not in states but in observables.
format Preprint
id arxiv_https___arxiv_org_abs_2209_12261
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle No-masking theorem for observables
Bhowmick, Swapnil
Srivastav, Abhay
Pati, Arun Kumar
Quantum Physics
The no-masking theorem for quantum information proves that it is impossible to encode an arbitrary input state into a larger bipartite entangled state such that the full information is stored in the correlation but the individual subsystems have no information about the input state. Here, we ask the question: Is it possible to mask an observable such that the information about the observable is available in the joint system, but individual subsystems reveal nothing about the imprints of the observable? This generalizes the notion of masking to observables. We show that a universal unitary that can mask an arbitrary observable in any dimension does not exist. For a qubit system, we show that the masking operation for a given observable is locally unitarily connected to the SWAP operation. This suggests a conservation law for information content of observables that goes beyond the conservation laws under symmetry operations. Furthermore, we prove that the unconditional no-bit commitment result follows from the no-masking theorem for observables. Our results can have important applications in quantum information and quantum communication where we encode information not in states but in observables.
title No-masking theorem for observables
topic Quantum Physics
url https://arxiv.org/abs/2209.12261