69 citations · 841 across the 44 of their papers we have counts for
44 papers
Polytopic Quantum Resource Theories: Geometry and Structures
Moein Naseri, Chirag Srivastava, Chandan Datta +2
Quantum resource theories provide a unifying framework to quantify, compare, and manipulate quantum resources under well-defined operational constraints. Here, we consider any reso…
Decoupling local classicality from classical explainability: A noncontextual model for bilocal classical theory and a locally-classical but contextual theory
Sina Soltani, Marco Erba, David Schmid +1
We construct an ontological model for the theory known as bilocal classical theory doi.org/10.1103/PhysRevA.102.052216. To our knowledge, this is only the second time that an ontol…
Noncontextual ontological models of operational probabilistic theories
Sina Soltani, Marco Erba, David Schmid +1
An experiment or theory is classically explainable if it can be reproduced by some noncontextual ontological model. In this work, we adapt the notion of ontological models and gene…
Generalised Process Theories
John H. Selby, Maria E. Stasinou, Matt Wilson +1
Process theories provide a powerful framework for describing compositional structures across diverse fields, from quantum mechanics to computational linguistics. Traditionally, the…
Shadows and subsystems of generalized probabilistic theories: when tomographic incompleteness is not a loophole for contextuality proofs
David Schmid, John H. Selby, Vinicius P. Rossi +2
It is commonly believed that failures of tomographic completeness undermine assessments of nonclassicality in noncontextuality experiments. In this work, we study how such failures…
Noncontextuality inequalities for prepare-transform-measure scenarios
David Schmid, Roberto D. Baldijão, John H. Selby +2
We provide the first systematic technique for deriving witnesses of contextuality in prepare-transform-measure scenarios. More specifically, we show how linear quantifier eliminati…
Symmetry-induced failures of tomographic locality: Constructing foil theories by twirling
Daniel Centeno, Marco Erba, Thomas D. Galley +7
Tomographic locality is a principle commonly used in the program of finding axioms that pick out quantum theory within the landscape of possible theories. The principle asserts the…
Robustness of contextuality under different types of noise as quantifiers for parity-oblivious multiplexing tasks
Amanda M. Fonseca, Vinicius P. Rossi, Roberto D. Baldijão +2
Generalised contextuality is the notion of nonclassicality powering up a myriad of quantum tasks, among which is the celebrated case of a two-party information processing task wher…
Kirkwood-Dirac representations beyond quantum states (and their relation to noncontextuality)
David Schmid, Roberto D. Baldijão, Yìlè Yīng +2
Kirkwood-Dirac representations of quantum states are increasingly finding use in many areas within quantum theory. Usually, representations of this sort are only applied to provide…
Every non-signalling channel is common-cause realizable
Paulo J. Cavalcanti, John H. Selby, Ana Belén Sainz
In this work we show that the set of non-signalling resources of a locally-tomographic generalised probabilistic theory (GPT), such as quantum and classical theory, coincides with…
Addressing some common objections to generalized noncontextuality
David Schmid, John H. Selby, Robert W. Spekkens
When should a given operational phenomenology be deemed to admit of a classical explanation? When it can be realized in a generalized-noncontextual ontological model. The case for…
Any consistent coupling between classical gravity and quantum matter is fundamentally irreversible
Thomas D. Galley, Flaminia Giacomini, John H. Selby
When gravity is sourced by a quantum system, there is tension between its role as the mediator of a fundamental interaction, which is expected to acquire nonclassical features, and…
Contextuality with vanishing coherence and maximal robustness to dephasing
Vinicius P. Rossi, David Schmid, John H. Selby +1
Generalized contextuality is a resource for a wide range of communication and information processing protocols. However, contextuality is not possible without coherence, and so can…
Time symmetry in quantum theories and beyond
John H. Selby, Maria E. Stasinou, Stefano Gogioso +1
There exists a stark tension among different formulations of quantum theory as some are inherently time-symmetric while others are time-asymmetric. This tension is crisply captured…
Simulating all multipartite non-signalling channels via quasiprobabilistic mixtures of local channels in generalised probabilistic theories
Paulo J. Cavalcanti, John H. Selby, Jamie Sikora +1
Non-signalling quantum channels -- relevant in, e.g., the study of Bell and Einstein-Podolsky-Rosen scenarios -- may be simulated via affine combinations of local operations in bip…
A linear program for testing nonclassicality and an open-source implementation
John H. Selby, Elie Wolfe, David Schmid +2
A well motivated method for demonstrating that an experiment resists any classical explanation is to show that its statistics violate generalized noncontextuality. We here formulat…
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 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…
Post-quantum steering is a stronger-than-quantum resource for information processing
Paulo J. Cavalcanti, John H. Selby, Jamie Sikora +2
We present the first instance where post-quantum steering is a stronger-than-quantum resource for information processing -- remote state preparation. In addition, we show that the…
Uniqueness of noncontextual models for stabilizer subtheories
David Schmid, Haoxing Du, John H. Selby +1
We give a complete characterization of the (non)classicality of all stabilizer subtheories. First, we prove that there is a unique nonnegative and diagram-preserving quasiprobabili…
A no-go theorem on the nature of the gravitational field beyond quantum theory
Thomas D. Galley, Flaminia Giacomini, John H. Selby
Recently, table-top experiments involving massive quantum systems have been proposed to test the interface of quantum theory and gravity. In particular, the crucial point of the de…
Correlations constrained by composite measurements
John H. Selby, Ana Belén Sainz, Victor Magron +2
How to understand the set of correlations admissible in nature is one outstanding open problem in the core of the foundations of quantum theory. Here we take a complementary viewpo…
Unscrambling the omelette of causation and inference: The framework of causal-inferential theories
David Schmid, John H. Selby, Robert W. Spekkens
Using a process-theoretic formalism, we introduce the notion of a causal-inferential theory: a triple consisting of a theory of causal influences, a theory of inferences (of both t…
Revisiting dynamics of quantum causal structures -- when can causal order evolve?
John H. Selby, Ana Belén Sainz, Paweł Horodecki
Recently, there has been substantial interest in studying the dynamics of quantum theory beyond that of states, in particular, the dynamics of channels, measurements, and higher-or…