Local state antimarking : Nonlocality without entanglement
- URL: http://arxiv.org/abs/2605.09710v1
- Date: Sun, 10 May 2026 19:18:07 GMT
- Title: Local state antimarking : Nonlocality without entanglement
- Abstract summary: We study quantum nonlocality within the framework of local state antidistinguishability.<n>We present an ensemble of product states that is not globally antidistinguishable, but choosing states from it, without replacement, produces such sequences.
- Score: 0.7874708385247353
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: A set of quantum states is said to be antidistinguishable if, upon being given a randomly chosen state, it is possible to identify a state that the system was definitively not prepared in. In this work, we begin with a study of quantum nonlocality within the framework of local state antidistinguishability (LSAD), and find that any ensemble of mutually orthogonal multipartite pure states is locally antidistinguishable. We then extend this paradigm by introducing the task of local state antimarking (LSAM), where a non-repetitive sequence from a known set of multipartite states is randomly selected and distributed to spatially separated parties who must identify at least one sequence that was not supplied using LOCC only. We present an ensemble of product states that is not globally antidistinguishable, but choosing states from it, without replacement, produces such sequences of states which are globally antidistinguishable but not locally-revealing a form of nonlocality without entanglement. Finally, we compare LSAD and LSAM with conclusive local state discrimination and conclusive local state marking. We demonstrate that no strict hierarchy exists between these paradigms: there exist product-state ensembles that permit one task while strictly forbidding the other, and vice versa.
Related papers
- Resourcefulness without Resource: Geometric Origins and Robustness [43.748379918040854]
A prevailing intuition holds that quantum protocols using only free states confer no operational advantage.<n>Known instances include nonlocality without entanglement and, more recently, nonstabilizerness without magic.<n>By contrast, non-free ensembles admit memory-assisted attacks that fully erase the gap, exposing a sharp operational asymmetry between free and resource-carrying ensembles.
arXiv Detail & Related papers (2026-06-30T11:30:00Z) - Integrating Local and Global Entropy for Uncertainty Quantification in LLMs [28.285388648427737]
We show that hidden-state geometric entropy (global uncertainty) and token-level entropy (local uncertainty) are statistically near-orthogonal.<n>We propose Global-Local Uncertainty (GLU), an unsupervised, single-pass score that fuses the two signals via a multiplicative gate.
arXiv Detail & Related papers (2026-06-02T20:57:14Z) - Nonlocality without entanglement in exclusion of quantum states [0.0]
We study the task of quantum state exclusion, focusing on antidistinguishability and its generalization to $x$-antidistinguishability.<n>Our results reveal striking differences between state exclusion and the more familiar task of state discrimination.
arXiv Detail & Related papers (2026-02-17T09:38:37Z) - Information recycling in coherent state discrimination [41.99844472131922]
We propose and analyze a strategy for distinguishing among N phase-symmetric coherent states.<n>We show that for N > 2, the "failure" states of UD retain residual information about the original input states.<n>Our results open up new possibilities for adaptive and sequential discrimination protocols in continuous-variable settings.
arXiv Detail & Related papers (2025-11-04T01:07:00Z) - Classifying locally distinguishable sets: No activation across bipartitions [0.0]
We provide different structures of locally distinguishable product and entangled states which do not allow the conversion.<n>In a multipartite system, this study becomes more involved as there exist multipartite locally distinguishable sets which cannot be converted to locally indistinguishable sets.
arXiv Detail & Related papers (2025-07-14T18:15:31Z) - Conclusive Local State Marking: More Nonlocality With No Entanglement [0.0]
Nonlocality exhibited by ensembles of composite quantum states is a striking nonclassical feature of quantum theory.<n>We show that certain ensembles of product states can exhibit a stronger form of nonlocality than entangled ensembles traditionally considered highly nonlocal.
arXiv Detail & Related papers (2025-06-11T05:59:42Z) - General detectability measure [45.85698554568285]
Distinguishing resource states from resource-free states is a fundamental task in quantum information.<n>We derived the optimal exponential decay rate of the failure probability for detecting a given $n$-tensor product state.
arXiv Detail & Related papers (2025-01-16T05:39:22Z) - Unextendibility, uncompletability, and many-copy indistinguishable ensembles [49.1574468325115]
We show that the complement of any bipartite pure entangled state is spanned by product states which form a nonorthogonal unextendible product basis (nUPB) of maximum cardinality.<n>We also report a class of multipartite many-copy indistinguishable ensembles for which local indistinguishability property increases with decreasing number of mixed states.
arXiv Detail & Related papers (2023-03-30T16:16:41Z) - Detection of Beyond-Quantum Non-locality based on Standard Local Quantum
Observables [46.03321798937856]
We show that device independent detection cannot distinguish beyond-quantum non-local states from standard quantum states.
This paper gives a device dependent detection based on local observables to distinguish any beyond-quantum non-local state from all standard quantum states.
arXiv Detail & Related papers (2023-01-10T20:19:34Z) - Locally unidentifiable subset of quantum states and its resourcefulness
in secret password distribution [0.0]
We introduce a hitherto unexplored form of quantum nonlocality, termed local subset unidentifiability.
We show that this nonlocality is stronger than other existing forms of quantum nonlocality.
We anticipate potential applications of this nonlocality for future quantum technologies.
arXiv Detail & Related papers (2022-09-22T12:17:11Z) - Genuine activation of nonlocality: From locally available to locally
hidden information [13.939388417767136]
Quantum nonlocality has different manifestations that, in general, are revealed by local measurements of parts of a composite system.
We show that there exist sets that are locally distinguishable but without local redundancy.
We suggest an application, namely, local hiding of information, that allows us to locally hide locally available information without losing any part.
arXiv Detail & Related papers (2021-04-24T12:02:48Z) - Unambiguous discrimination of Fermionic states through local operations
and classical communication [68.8204255655161]
The paper studies unambiguous discrimination of Fermionic states through local operations and classical communication (LOCC)
We show that it is not always possible to distinguish two Fermionic states through LOCC unambiguously with the same success probability as if global measurements were allowed.
arXiv Detail & Related papers (2020-09-11T21:08:52Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.