36 citations · 325 across the 50 of their papers we have counts for
51 papers · 1 filter
Negative quasiprobabilities redistribute (and complex ones reduce) the information in unabsorbed photons
Jonte R. Hance
Negative Kirkwood--Dirac quasiprobabilities are credited with the quantum advantage of interaction-free measurement and postselected metrology. We test that claim on the task inter…
Quantum Approximate Optimisation Algorithm for Protein Sidechain Packing
Sebastian O. M. Stewart, Nick Chancellor, Jonte R Hance +1
Sidechain packing is a critical stage in protein folding, with direct implications for structure-based drug discovery. Google DeepMind's tool, AlphaFold2, predicts protein backbone…
Frame dependence of Kochen-Specker contextuality for relativistic spin systems
Jonte R. Hance, Ruben Campos Delgado
We ask whether Kochen-Specker contextuality is Lorentz invariant. On the full Hilbert space, it is, since boosts act unitarily. Restricted to spin, it is not: momentum acts as an e…
The Quantum Plumber's Problem
Nicolas G. Underwood, Holger F. Hofmann, Jonte R. Hance
Recent work quantified the notion of quantum counterfactual gain for an extended Elitzur-Vaidman bomb test style scenario, through a connection to the negativity of the Kirkwood-Di…
Why three? A two-level system with four mutually unbiased questions
Jonte R. Hance
Two sharp yes/no questions are mutually unbiased if and only if their involutions anticommute. A set of unbiased questions is therefore a Clifford algebra, whose maximal size is od…
Impact of Data Loss in Postprocessing on Training and Inference of Quantum Neural Networks
Soraya V. Panambalom, Edoardo Altamura, Nick Chancellor +1
As quantum hardware scales to larger devices, the classical software layers that interface with it must evolve in step. Postprocessing routines developed and tested primarily in si…
Convex conservation of von Neumann entropy implies unitarity or antiunitarity
Nicolas G. Underwood, Jonte R. Hance
On the space of density matrices , Kadison's theorem establishes that all invertible convex transformations are unitarity or antiunitary. For a finite Hilber…
Implementation of nonlocal multi-photon interference by mode swapping
Holger F. Hofmann, Yuki Kodama, Jonte R. Hance
Multi-photon interference can be observed using independently generated photons as input. In the most simple case, these photons meet up at a beam splitter, resulting in quantum in…
What meter interference can tell us about the statistics of weak measurements
Holger F. Hofmann, Tomonori Matsushita, Masayoshi Isobe +1
It is widely assumed that the quantum fluctuations of the meter readout in a weak measurement make it impossible to identify the contributions originating from the individual value…
Phase-Space Representations of Quantum Error-Correcting Codes
Enrico Bozzetto, Jonte R. Hance
We connect the structure theorem for quasiprobability representations to quantum error correction. For a code space invariant under a subgroup of an extended Weyl-Heisenberg group,…
Classical Limit: Dissipation of Spekkens' Generalised Contextuality under Decoherence
Enrico Bozzetto, Jonte R. Hance
When does a decohering quantum system become classical? Generalised noncontextuality gives one criterion, for scenarios rich enough in preparations: a system is classical once its…
How to unitarily map between any two pure states with a single closed-form exponential
Peter T. J. Bradshaw, Marcus Gouveia, Jonte R. Hance
It is well-known that any two pure quantum states (in the same Hilbert space) can be mapped to any other using unitary transformations. However, previous approaches to this problem…
The non-local Hong-Ou-Mandel effect
Yuki Kodama, Jonte R. Hance, Holger F. Hofmann
Two-photon interference effects arise because photons are indistinguishable particles. In the wellknown Hong-Ou-Mandel (HOM) effect, the transmission of two photons at a beam split…
Warring Contextualities - Provably Classical vs Provably Nonclassical
Enrico Bozzetto, Jonte R. Hance
In the literature, there are two differing definitions of contextuality: Kochen and Specker's, and Spekkens' (or ``generalised''). However, researchers using one of these definitio…
Noncontextual versus contextual interferometry
Jonte R. Hance, Jakov Krnic, Jan-Åke Larsson
Feynman famously said that single-particle interference is ``a phenomenon which is impossible to explain in any classical way, and which has in it the heart of quantum mechanics.''…
Quantum-Like Correlations from Local Hidden-Variable Theories Under Conservation Law
Alejandro J. Garza, Jonte R. Hance
The precision with which we can measure operators that do not commute with conserved quantities is limited by the need to preserve the associated global symmetries. We show how to…
Limits of Absoluteness of Observed Events in Timelike Scenarios: A No-Go Theorem
Sumit Mukherjee, Jonte R. Hance
Wigner's Friend-type paradoxes challenge the assumption that events are absolute -- that when we measure a system, we obtain a single result, which is not relative to anything or a…
Reply to "Counterfactual communication not achieved yet -- A Comment on Salih et al. (2022)"
Hatim Salih, Jonte R. Hance, Will McCutcheon +1
In his Comment on our recent paper ``The laws of physics do not prohibit counterfactual communication'', \textit{npj Quantum Information} (2022) 8:60, Popescu argues that the claim…
Quantum Contextuality Requires Counterfactual Gain
Yuki Sagawa, Jonte R. Hance, Holger F. Hofmann +1
Quantum contextuality, where measurement outcomes depend on the measurement context, implies a failure of classical realism in quantum systems. As recently shown, the transition be…
Sufficiency of the counterfactual account of Lüders' rule to rule out ontological models of quantum mechanics
Alisson Tezzin, Bárbara Amaral, Jonte R. Hance
Ontological models, as used in the generalised contextuality literature, play a central role in current research on quantum foundations, providing a framework for defining classica…
Deterministic Underlying States are incompatible with a Counterfactual account of Lüders' rule
Alisson Tezzin, Bárbara Amaral, Jonte R. Hance
In this work, we show that a counterfactual account of L"uders' rule -- which we argue is naturally implied by the mathematical structure of the rule itself -- rules out underlying…
External quantum fluctuations select measurement contexts
Jonte R. Hance, Ming Ji, Tomonori Matsushita +1
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…
Fermion and Boson Pairs in Beamsplitters and MZIs
Jonte R. Hance
In this short Topical Review, we look at something typically considered trivial, but not given formally elsewhere -- the behaviour of first multiple fermions, then multiple bosons,…
Counterfactuality, back-action, and information gain in multi-path interferometers
Jonte R. Hance, Tomonori Matsushita, Holger F. Hofmann
The presence of an absorber in one of the paths of an interferometer changes the output statistics of that interferometer in a fundamental manner. Since the individual quantum part…