215 citations · 924 across the 26 of their papers we have counts for
26 papers
Nonclassicality in correlations without causal order
Ravi Kunjwal, Ognyan Oreshkov
Bell scenarios are multipartite scenarios that exclude any signalling between parties. This leads to a strict hierarchy of classical, quantum, and non-signalling correlations in su…
Quantum researcher mobility: the wonderful wizard of Oz who paid for Dorothy's Visa fees
Mehul Malik, Elizabeth Agudelo, Ravi Kunjwal
Historically, science has benefited greatly through the mobility of researchers, whether it has been due to large-scale conflict, the search for new opportunities or a lack thereof…
Trading causal order for locality
Ravi Kunjwal, Ämin Baumeler
Quantum theory admits ensembles of quantum nonlocality without entanglement (QNLWE). These ensembles consist of seemingly classical states (they are perfectly distinguishable and n…
Accessible fragments of generalized probabilistic theories, cone equivalence, and applications to witnessing nonclassicality
John H. Selby, David Schmid, Elie Wolfe +3
The formalism of generalized probabilistic theories (GPTs) was originally developed as a way to characterize the landscape of conceivable physical theories. Thus, the GPT describin…
Contextuality in composite systems: the role of entanglement in the Kochen-Specker theorem
Victoria J Wright, Ravi Kunjwal
The Kochen--Specker (KS) theorem reveals the nonclassicality of single quantum systems. In contrast, Bell's theorem and entanglement concern the nonclassicality of composite quantu…
Contextuality without incompatibility
John H. Selby, David Schmid, Elie Wolfe +3
The existence of incompatible measurements is often believed to be a feature of quantum theory which signals its inconsistency with any classical worldview. To prove the failure of…
Qualitative equivalence between incompatibility and Bell nonlocality
Shiv Akshar Yadavalli, Nikola Andrejic, Ravi Kunjwal
Measurements in quantum theory can fail to be jointly measurable. Like entanglement, this incompatibility of measurements is necessary but not sufficient for violating Bell inequal…
Contextuality in entanglement-assisted one-shot classical communication
Shiv Akshar Yadavalli, Ravi Kunjwal
We consider the problem of entanglement-assisted one-shot classical communication. In the zero-error regime, entanglement can increase the one-shot zero-error capacity of a family…
Understanding the interplay of entanglement and nonlocality: motivating and developing a new branch of entanglement theory
David Schmid, Thomas C. Fraser, Ravi Kunjwal +3
A standard approach to quantifying resources is to determine which operations on the resources are freely available, and to deduce the partial order over resources that is induced…
Joint measurability structures realizable with qubit measurements: incompatibility via marginal surgery
Nikola Andrejic, Ravi Kunjwal
Measurements in quantum theory exhibit incompatibility, i.e., they can fail to be jointly measurable. An intuitive way to represent the (in)compatibility relations among a set of m…
Towards Spacetime Entanglement Entropy for Interacting Theories
Yangang Chen, Lucas Hackl, Ravi Kunjwal +3
Entanglement entropy of quantum fields in gravitational settings is a topic of growing importance. This entropy of entanglement is conventionally computed relative to Cauchy hypers…
The Characterization of Noncontextuality in the Framework of Generalized Probabilistic Theories
David Schmid, John Selby, Elie Wolfe +2
To make precise the sense in which the operational predictions of quantum theory conflict with a classical worldview, it is necessary to articulate a notion of classicality within…
Quantifying Bell: the Resource Theory of Nonclassicality of Common-Cause Boxes
Elie Wolfe, David Schmid, Ana Belén Sainz +2
We take a resource-theoretic approach to the problem of quantifying nonclassicality in Bell scenarios. The resources are conceptualized as probabilistic processes from the setting…
Anomalous weak values and contextuality: robustness, tightness, and imaginary parts
Ravi Kunjwal, Matteo Lostaglio, Matthew F. Pusey
Weak values are quantities accessed through quantum experiments involving weak measurements and post-selection. It has been shown that 'anomalous' weak values (those lying beyond t…
Hypergraph framework for irreducible noncontextuality inequalities from logical proofs of the Kochen-Specker theorem
Ravi Kunjwal
Kochen-Specker (KS) theorem reveals the inconsistency between quantum theory and any putative underlying model of it satisfying the constraint of KS-noncontextuality. A logical pro…
Almost Quantum Correlations are Inconsistent with Specker's Principle
Tomáš Gonda, Ravi Kunjwal, David Schmid +2
Ernst Specker considered a particular feature of quantum theory to be especially fundamental, namely that pairwise joint measurability of sharp measurements implies their global jo…
Beyond the Cabello-Severini-Winter framework: Making sense of contextuality without sharpness of measurements
Ravi Kunjwal
We develop a hypergraph-theoretic framework for Spekkens contextuality applied to Kochen-Specker (KS) type scenarios that goes beyond the Cabello-Severini-Winter (CSW) framework. T…
From statistical proofs of the Kochen-Specker theorem to noise-robust noncontextuality inequalities
Ravi Kunjwal, Robert W. Spekkens
The Kochen-Specker theorem rules out models of quantum theory wherein projective measurements are assigned outcomes deterministically and independently of context. This notion of n…
Contextuality beyond the Kochen-Specker theorem
Ravi Kunjwal
When it isn't possible to tell two distinct experimental procedures apart purely from their input/output statistics, then it seems a plausible hypothesis that the two procedures mu…
From the Kochen-Specker theorem to noncontextuality inequalities without assuming determinism
Ravi Kunjwal, Robert W. Spekkens
The Kochen-Specker theorem demonstrates that it is not possible to reproduce the predictions of quantum theory in terms of a hidden variable model where the hidden variables assign…
An experimental test of noncontextuality without unwarranted idealizations
Michael D. Mazurek, Matthew F. Pusey, Ravi Kunjwal +2
To make precise the sense in which nature fails to respect classical physics, one requires a formal notion of classicality. Ideally, such a notion should be defined operationally,…
Fine's theorem, noncontextuality, and correlations in Specker's scenario
Ravi Kunjwal
A characterization of noncontextual models which fall within the ambit of Fine's theorem is provided. In particular, the equivalence between the existence of three notions is made…
A note on the joint measurability of POVMs and its implications for contextuality
Ravi Kunjwal
The purpose of this note is to clarify the logical relationship between joint measurability and contextuality for quantum observables in view of recent developments [1-4].
Quantum realization of arbitrary joint measurability structures
Ravi Kunjwal, Chris Heunen, Tobias Fritz
In many a traditional physics textbook, a quantum measurement is defined as a projective measurement represented by a Hermitian operator. In quantum information theory, however, th…