Nonanomalous measure of realism-based nonlocality

2020

Found Phys

Section: Elements Of Realitymentioning

confidence: 99%

Hardy’s Paradox as a Demonstration of Quantum Irrealism

Engelbert

2020

Found Phys

“…By maximizing the contextual realism-based nonlocality over all possible contexts, Gomes and Angelo then introduced the bipartite realism-based nonlocality [28]…”

Section: Preliminary Conceptsmentioning

confidence: 99%

“…Inspired by the lack of such a clear link between realism and violations of the local causality hypothesis, a notion of nonlocality has recently been put forward that makes explicit use of a criterion of realism [27]. This novel aspect of nonlocality counts with a nonanomalous quantifier, is remarkably more resilient to noise than other quantum resources, and reduces to bipartite entanglement for pure states [28,29].…”

mentioning

confidence: 99%

Tripartite realism-based quantum nonlocality

Fucci

2019

Phys. Rev. A

Self Cite

From an operational criterion of physical reality, a quantifier of realism-based nonlocality was recently introduced for two-part quantum states. This measure has shown to capture aspects that are rather different from Bell nonlocality. Here we take a step further and introduce a tripartite realism-based nonlocality quantifier. We show that this measure reduces to genuine tripartite entanglement for a certain class of pure tripartite states and manifests itself in correlated mixed states even in the absence of quantum correlations. A case study for noisy GHZ and W states points out the existence of scenarios where the realism-based nonlocality is monogamous.

“…where The BA criterion for the occurrence of realism, (2), and the quantification of its violation, (3), count by now with further developments and applications [46][47][48][49]. All these works are, however, strictly connected with discrete-spectrum observables.…”

Section: Basic Concepts and Uncertainty Relationmentioning

confidence: 99%

“…A few years ago, Bilobran and Angelo (BA) introduced a measurementbased criterion of reality which allowed for the quantification of the degree of reality of a discrete-spectrum observable for a given multipartite quantum state [45]. This approach led to further foundational developments, as, for instance, the definition of the realism-based nonlocality [46,47], which captures nonlocal aspects that are dramatically different from Bell nonlocality, and the derivation of an information-reality complementarity relation [48], which is shown to apply even to scenarios of weak disturbances. Interestingly, this framework received experimental corroboration via weak measurements implemented in a photonic platform [49].…”

Section: Introductionmentioning

confidence: 99%

Quantifying continuous-variable realism

Freire

2019

Phys. Rev. A

Self Cite

The debate instigated by the seminal works of Einstein, Podolsky, Rosen, and Bell put the notions of realism and nonlocality at the core of almost all philosophical and physical discussions underlying the foundations of quantum mechanics. However, while experimental criteria and quantifiers are by now well established for nonlocality, there is no clear quantitative measure for the degree of reality associated with continuous variables such as position and momentum. This work aims at filling this gap. Considering position and momentum as effectively discrete observables, we implement an operational notion of projective measurement and, from that, a criterion of reality for theses quantities. Then we introduce a quantifier for the degree of irreality of a discretized continuous variable which, when applied to the conjugated pair position-momentum, is shown to obey an uncertainty relation, meaning that quantum mechanics prevents classical realism for conjugated quantities. As an application of our formalism, we study the emergence of elements of reality in an instance where a Gaussian state is submitted to the dissipative dynamics implied by the Caldirola-Kanai Hamiltonian. In particular, at equilibrium, we make some links with the measurement problem and identify aspects that can be taken as the quantum counterpart for the notion of rest.