External quantum fluctuations select measurement contexts

• URL: http://arxiv.org/abs/2501.04664v1
• Date: Wed, 08 Jan 2025 18:22:34 GMT
• Title: External quantum fluctuations select measurement contexts
• Authors: Jonte R. Hance, Ming Ji, Tomonori Matsushita, Holger F. Hofmann,
• Abstract summary: Quantum paradoxes show that the outcomes of different quantum measurements cannot be described by a single measurement-independent reality. We show that external quantum fluctuations, represented by the initial state of the measurement apparatus, play an essential role in the selection of the context.
• Score: 0.03749861135832072
• License:
• Abstract: Quantum paradoxes show that the outcomes of different quantum measurements cannot be described by a single measurement-independent reality. Any theoretical description of a quantum measurement implies the selection of a specific measurement context. Here, we investigate generalised quantum measurements, in order to identify the mechanism by which this specific context is selected. We show that external quantum fluctuations, represented by the initial state of the measurement apparatus, play an essential role in the selection of the context. This has the non-trivial consequence that, when considering measurements other than just idealised projection-valued measures, different outcomes of a single measurement setup can represent different measurement contexts. We further show this result underpins recent claims that contextuality can occur in scenarios without measurement incompatibility.

Related papers

• Entanglement measurement based on convex hull properties [0.0]
  We will propose a scheme for measuring quantum entanglement, which starts with treating the set of quantum separable states as a convex hull of quantum separable pure states. Although a large amount of data is required in the measurement process, this method is not only applicable to 2-qubit quantum states, but also a entanglement measurement method that can be applied to any dimension and any fragment.
  arXiv  Detail & Related papers  (2024-11-08T08:03:35Z)
• Effect of the readout efficiency of quantum measurement on the system entanglement [44.99833362998488]
  We quantify the entanglement for a particle on a 1d quantum random walk under inefficient monitoring. We find that the system's maximal mean entanglement at the measurement-induced quantum-to-classical crossover is in different ways by the measurement strength and inefficiency.
  arXiv  Detail & Related papers  (2024-02-29T18:10:05Z)
• Measurement-Device-Independent Detection of Beyond-Quantum State [53.64687146666141]
  We propose a measurement-device-independent (MDI) test for beyond-quantum state detection. We discuss the importance of tomographic completeness of the input sets to the detection.
  arXiv  Detail & Related papers  (2023-12-11T06:40:13Z)
• Enhanced Entanglement in the Measurement-Altered Quantum Ising Chain [43.80709028066351]
  Local quantum measurements do not simply disentangle degrees of freedom, but may actually strengthen the entanglement in the system. This paper explores how a finite density of local measurement modifies a given state's entanglement structure.
  arXiv  Detail & Related papers  (2023-10-04T09:51:00Z)
• Quantitative relations between different measurement contexts [0.054390204258189995]
  In quantum theory, a measurement context is defined by an basis in a Hilbert space, where each basis vector represents a specific measurement outcome. We show that the probabilities that describe the paradoxes of quantum contextuality can be derived from a very small number of inner products. The nonlocality of quantum entanglement can be traced back to a local inner product representing the relation between measurement contexts in only one system.
  arXiv  Detail & Related papers  (2023-05-24T08:26:09Z)
• Quantifying measurement-induced quantum-to-classical crossover using an open-system entanglement measure [49.1574468325115]
  We study the entanglement of a single particle under continuous measurements. We find that the entanglement at intermediate time scales shows the same qualitative behavior as a function of the measurement strength.
  arXiv  Detail & Related papers  (2023-04-06T09:45:11Z)
• Experimentally determining the incompatibility of two qubit measurements [55.41644538483948]
  We describe and realize an experimental procedure for assessing the incompatibility of two qubit measurements. We demonstrate this fact in an optical setup, where the qubit states are encoded into the photons' polarization degrees of freedom.
  arXiv  Detail & Related papers  (2021-12-15T19:01:44Z)
• How well can we guess the outcome of measurements of non-commuting observables? [0.0]
  Heisenberg's uncertainty relation says there is an ultimate limit to how precisely we may predict the outcome of position and momentum measurements on a quantum system. We show that this limit may be violated by an arbitrarily large factor if one aims, instead, to guess the unknown value of a past measurement.
  arXiv  Detail & Related papers  (2021-03-30T13:31:36Z)
• Observing a Topological Transition in Weak-Measurement-Induced Geometric Phases [55.41644538483948]
  Weak measurements in particular, through their back-action on the system, may enable various levels of coherent control. We measure the geometric phases induced by sequences of weak measurements and demonstrate a topological transition in the geometric phase controlled by measurement strength. Our results open new horizons for measurement-enabled quantum control of many-body topological states.
  arXiv  Detail & Related papers  (2021-02-10T19:00:00Z)
• Contextuality of quantum fluctuations characterized by conditional weak values of entangled states [0.0]
  Quantum theory indicates that the effective distribution of values taken by the physical property depends on the specific measurement context based on which these values are determined and weak values have been identified as the contextual values. Here, the relation between classical statistics and quantum contextuality is explored by considering systems entangled with a quantum reference. The results show that mixed state statistics are consistent with a wide range of potential contexts, indicating that the precise definition of a context requires maximal quantum coherence in both state preparation and measurement.
  arXiv  Detail & Related papers  (2020-09-14T01:50:43Z)
• Quantifying coherence of quantum measurements [0.0]
  We show that any statistical distance can be adopted to define a coherence monotone of measurement. We specifically introduce a coherence monotone of measurement in terms of off-diagonal elements of Positive-Operator-Valued Measure (POVM) components.
  arXiv  Detail & Related papers  (2020-08-10T09:57:28Z)

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.