English
Related papers

Related papers: Picturing general quantum subsystems

200 papers

In continuous-variable quantum computation, identifying key elements that enable a quantum computational advantage is a long-standing issue. Starting from the standard results on the necessity of Wigner negativity, we develop a…

Quantum Physics · Physics 2025-03-12 Massimo Frigerio , Antoine Debray , Nicolas Treps , Mattia Walschaers

We provide a universal construction of the category of finite-dimensional C*-algebras and completely positive trace-nonincreasing maps from the rig category of finite-dimensional Hilbert spaces and unitaries. This construction, which can be…

Quantum Physics · Physics 2023-11-16 Pablo Andrés-MartíÂ-nez , Chris Heunen , Robin Kaarsgaard

We introduce categories of extended Gaussian maps and Gaussian relations which unify Gaussian probability distributions with relational nondeterminism in the form of linear relations. Both have crucial and well-understood applications in…

Logic in Computer Science · Computer Science 2023-06-08 Dario Stein , Richard Samuelson

A Bayesian approach to the classification problem is proposed in which random partitions play a central role. It is argued that the partitioning approach has the capacity to take advantage of a variety of large-scale spatial structures, if…

Statistics Theory · Mathematics 2007-06-13 Marc A. Coram

Quantum theory exhibits various nonclassical features, such as measurement incompatibility, contextuality, steering, and Bell nonlocality, which distinguish it from classical physics. These phenomena are often studied separately, but they…

Quantum Physics · Physics 2026-05-25 Tim Achenbach , Andreas Bluhm , Leevi Leppäjärvi , Ion Nechita , Martin Plávala

The aim in many sciences is to understand the mechanisms that underlie the observed distribution of variables, starting from a set of initial hypotheses. Causal discovery allows us to infer mechanisms as sets of cause and effect…

Machine Learning · Computer Science 2025-03-05 Ashka Shah , Adela DePavia , Nathaniel Hudson , Ian Foster , Rick Stevens

We study quantum process tomography given the prior information that the map is a unitary or close to a unitary process. We show that a unitary map on a $d$-level system is completely characterized by a minimal set of $d^2{+}d$ elements…

Quantum Physics · Physics 2014-07-23 Charles H. Baldwin , Amir Kalev , Ivan H. Deutsch

We study the non-uniqueness of factorizations of non zero-divisors into atoms (irreducibles) in noncommutative rings. To do so, we extend concepts from the commutative theory of non-unique factorizations to a noncommutative setting. Several…

Rings and Algebras · Mathematics 2015-09-03 Nicholas R. Baeth , Daniel Smertnig

The operator algebra of fermionic modes is isomorphic to that of qubits, the difference between them is twofold: the embedding of subalgebras corresponding to mode subsets and multiqubit subsystems on the one hand, and the parity…

One of the most basic notions in physics is the partitioning of a system into subsystems, and the study of correlations among its parts. In this work, we explore these notions in the context of quantum reference frame (QRF) covariance, in…

In this paper, we show how a construction of an implicit complexity model can be implemented using concepts coming from the core of von Neumann algebras. Namely, our aim is to gain an understanding of classical computation in terms of the…

Computational Complexity · Computer Science 2009-12-31 Marco Pedicini , Mario Piazza

Simulating complex systems remains an ongoing challenge for classical computers, while being recognised as a task where a quantum computer has a natural advantage. In both digital and analogue quantum simulations the system description is…

Quantum Physics · Physics 2025-03-03 Maite Arcos , Harriet Apel , Toby Cubitt

Subsystems of entangled quantum systems are not traditionally described in a local way. This paper begins to address the issue by constructing an explicit local hidden variable theory for quantum subsystems. The interpretation is based on a…

Quantum Physics · Physics 2017-08-23 Adam Brownstein

Unsupervised image segmentation aims at clustering the set of pixels of an image into spatially homogeneous regions. We introduce here a class of Bayesian nonparametric models to address this problem. These models are based on a combination…

Machine Learning · Statistics 2016-02-10 Richard Yi Da Xu , Francois Caron , Arnaud Doucet

This paper proposes the design and implementation strategy of a novel computing architecture, the Factor Machine. The work is a step towards a general-purpose parallel system operating in a non-sequential manner, exploiting…

Hardware Architecture · Computer Science 2024-02-21 Piotr Dudek

Using a representation of multichannel quantum defect theory in terms of a quantum Poincar\'e map for bound Rydberg molecules, we apply Jung's scattering map to derive a generalized quantum map, that includes the continuum. We show, that…

Chemical Physics · Physics 2009-09-29 Barbara Dietz , Maurice Lombardi , Thomas H Seligman

Given an undirected graph representing similarities between a set of items and an additive measure evaluating the items, we treat the position of a special subset of items in an ordinal ranking through a collection of combinatorial…

Data Structures and Algorithms · Computer Science 2026-05-05 Samuel Boardman

We develop a compositional framework for generalized reversible computing using copy-discard categories and resource theories. We introduce partitioned matrices between partitioned sets as subdistribution matrices which preserve the…

Category Theory · Mathematics 2025-11-18 Clémence Chanavat , Priyaa Varshinee Srinivasan

We study the question of how to decompose Hilbert space into a preferred tensor-product factorization without any pre-existing structure other than a Hamiltonian operator, in particular the case of a bipartite decomposition into "system"…

Quantum Physics · Physics 2021-02-24 Sean M. Carroll , Ashmeet Singh

We identify morphisms of strong profunctors as a categorification of quantum supermaps. These black-box generalisations of diagrams-with-holes are hence placed within the broader field of profunctor optics, as morphisms in the category of…

Quantum Physics · Physics 2024-07-02 James Hefford , Matt Wilson