A5010799698- Quantum Mechanics and Applications
- Quantum Information and Cryptography
- Philosophy and History of Science
- Advanced Thermodynamics and Statistical Mechanics
- Quantum Computing Algorithms and Architecture
- Biofield Effects and Biophysics
- Statistical Mechanics and Entropy
- Bayesian Modeling and Causal Inference
- Cosmology and Gravitation Theories
- Computational Drug Discovery Methods
- Black Holes and Theoretical Physics
- Noncommutative and Quantum Gravity Theories
- Orbital Angular Momentum in Optics
- advanced mathematical theories
- Experimental and Theoretical Physics Studies
- Metaheuristic Optimization Algorithms Research
- Chaos-based Image/Signal Encryption
- Computability, Logic, AI Algorithms
- Quantum Electrodynamics and Casimir Effect
- Neural Networks and Applications
- Thermal Radiation and Cooling Technologies
- Relativity and Gravitational Theory
- Gaussian Processes and Bayesian Inference
- Strong Light-Matter Interactions
- Molecular spectroscopy and chirality
University of Massachusetts Boston
2020-2023
Boston University
2021
Stellenbosch University
2021
Austrian Academy of Sciences
2014-2020
Universidade Federal do Rio Grande do Norte
2017-2020
Institute for Quantum Optics and Quantum Information Innsbruck
2017
University of Vienna
2014-2017
The University of Queensland
2010-2013
Centre for Quantum Computation and Communication Technology
2011
Queensland University of Technology
2010-2011
A causal model is an abstract representation of a physical system as directed acyclic graph (DAG), where the statistical dependencies are encoded using graphical criterion called 'd-separation'. Recent work by Wood and Spekkens shows that models cannot, in general, provide faithful quantum systems. Since d-separation encodes form Reichenbach's common cause principle (RCCP), whose validity questionable mechanics, we propose generalized separation rule does not assume RCCP. We prove new...
Models of quantum systems on curved space-times lack sufficient experimental verification. Some speculative theories suggest that properties, such as entanglement, may exhibit entirely different behavior to purely classical systems. By measuring this effect or thereof, we can test the hypotheses behind several models. For instance, predicted by Ralph and coworkers [T C Ralph, G J Milburn, T Downes, Phys. Rev. A, 79(2):22121, 2009, Pienaar, New Journal Physics, 16(8):85008, 2014], a bipartite...
Wave-particle duality has become one of the flagships quantum mechanics. This counterintuitive concept is highlighted in a delayed-choice experiment, where experimental setup that reveals either particle or wave nature system decided after entered apparatus. Here we consider experiments from perspective device-independent causal models and show their equivalence to prepare-and-measure scenario. Within this framework, Wheeler's original proposal its variant using control simple classical...
Abstract The unification of the theory relativity and quantum mechanics is a long-standing challenge in contemporary physics. Experimental techniques optics have only recently reached maturity required for investigation systems under influence non-inertial motion, such as being held at rest gravitational fields, or subjected to uniform accelerations. Here, we report on experiments which genuine state an entangled photon pair exposed series different We measure entanglement witness g-values...
Toy models for quantum evolution in the presence of closed timelike curves have gained attention recent literature due to strange effects they predict. The circuits that give rise these appear quite abstract and contrived, as require nontrivial interactions between future past lead infinitely recursive equations. We consider special case which there is no interaction inside curve, referred an open curve (OTC), only local effect increase time elapsed by a clock carried system. Remarkably,...
This paper presents a framework for Quantum causal modeling based on the interpretation of causality as relation between an observer's probability assignments to hypothetical or counterfactual experiments. The is principle `causal sufficiency': that it should be possible make inferences about interventions using only probabilities from single `reference experiment' plus structure in form DAG. leads several interesting results: we find quantum measurements deserve special status distinct...
In the literature on quantum reference frames, internal (relative) properties of a system are defined as those which preserved under an arbitrary change frame. For spins, these all by proper spatial rotations laboratory. However, this approach does not account for hypothetical possibility laboratory becoming entangled to system, described second (the `Wigner's friend' scenario), in case relationship between two laboratories is rotation, but fundamentally quantum. To overcome limitation, we...
The event formalism is a nonlinear extension of quantum field theory designed to be compatible with the closed time-like curves that appear in general relativity. Whilst reducing standard flat space-time leads testably different predictions for entanglement distribution curved space. In this paper we introduce more version and use it analyse practicality an experimental test its Earthʼs gravitational well.
The authors use Bayesian probability theory to extend the ``QBism'' interpretation of quantum mechanics by showing how one may derive Born's rule from a set assumptions where state and measurement are described relative ``reference measurement.'' result gives insight into rule, even if does not support subjective underlying QBism.
Abstract A causal scenario is a graph that describes the cause and effect relationships between all relevant variables in an experiment. deemed ‘not interesting’ if there no device-independent way to distinguish predictions of classical physics from any generalised probabilistic theory (including quantum mechanics). Conversely, interesting one which exists gap different operational theories, as occurs for example Bell-type experiments. Henson, Lal Pusey (HLP) recently proposed sufficient...
Recently, there has been much interest in the evolution of quantum particles on closed time-like curves (CTCs). However, such models typically assume point-like with only two degrees freedom - a very questionable assumption given relativistic setting problem. We show that it is possible to generalise Deutsch model CTCs fields using equivalent circuit formalism. give examples for coherent, squeezed and single-photon states interacting CTC via beamsplitter. The then generalised further account...
We construct a qubit algebra from field creation and annihilation operators acting on global vacuum state. Particles to be used as qubits are created the by near-deterministic single particle source. Our formulation makes space-time dependence of explicit, preparing way for quantum computation within framework. The method can generalized deal with interacting whose wavepackets not perfectly matched each other. give an example how calculate Heisenberg evolution simple two-qubit circuit,...
Reichenbach's principle asserts that if two observed variables are found to be correlated, then there should a causal explanation of these correlations.Furthermore, the is in terms common cause, conditional probability distribution over given complete cause factorize.The generalized by formalism models, which relationships among constrain form their joint distribution.In quantum case, however, correlations Bell experiments cannot explained manner would seem demand.Motivated this, we...
Nonlinear modifications to the laws of quantum mechanics have been proposed as a possible way consistently describe information processing in presence closed timelike curves. These recently generated controversy due exotic information-theoretic effects, including breaking cryptography and radically speeding up both classical computers. The physical interpretation such theories, however, is still unclear. We consider large class operationally-defined theories that contain "nonlinear boxes"...
Modern approaches to causal modeling give a central role interventions, which require the active input of an observer and introduces explicit `causal arrow time'. Causal models typically adopt mechanistic interpretation, according direction is intrinsic process being studied. Here we investigate whether might be contribution from observer, rather than property process. Working within counterfactual non-mechanistic interpretation developed in arXiv:1806.00895, propose definition `quantum...
According to the subjective Bayesian interpretation of quantum theory (QBism), mechanics is a tool that an agent would be wise use when making bets about natural phenomena. In particular, Born rule understood decision-making norm, ideal which one should strive meet even if usually falling short in practice. What required for make decisions conform mechanics? Here we investigate how realistic (hence non-ideal) might deviate from its decisions. To do so simulate simple as...
It is currently unknown whether the laws of physics permit time travel into past. While general relativity indicates theoretical possibility causality violation, it now widely accepted that a theory quantum gravity must play an essential role in such cases. As striking example, logical paradoxes usually associated with violation can be resolved by effects. We ask explicit construction allows might turn teach us something about gravity. Taking toy model Deutsch as starting point, Part I we...