Quantum

Quantum has published 229 Papers in 4 Volumes, as well as 31 Views in Quantum Views.

Quantum SDP-Solvers: Better upper and lower bounds

Joran van Apeldoorn, András Gilyén, Sander Gribling, and Ronald de Wolf,

Quantum 4, 230 (2020).

Brandão and Svore [14] recently gave quantum algorithms for approximately solving semidefinite programs, which in some regimes are faster than the best-possible classical algorithms in terms…

Paper

Maximum $N$-body correlations do not in general imply genuine multipartite entanglement

Christopher Eltschka and Jens Siewert,

Quantum 4, 229 (2020).

The existence of correlations between the parts of a quantum system on the one hand, and entanglement between them on the other, are different properties. Yet, one intuitively would identify…

Paper

Computational universality of symmetry-protected topologically ordered cluster phases on 2D Archimedean lattices

Austin K. Daniel, Rafael N. Alexander, and Akimasa Miyake,

Quantum 4, 228 (2020).

What kinds of symmetry-protected topologically ordered (SPTO) ground states can be used for universal measurement-based quantum computation in a similar fashion to the 2D cluster state? 2D S…

Paper

Completely positive master equation for arbitrary driving and small level spacing

Evgeny Mozgunov and Daniel Lidar,

Quantum 4, 227 (2020).

Markovian master equations are a ubiquitous tool in the study of open quantum systems, but deriving them from first principles involves a series of compromises. On the one hand, the Redfield…

Paper

Data re-uploading for a universal quantum classifier

Adrián Pérez-Salinas, Alba Cervera-Lierta, Elies Gil-Fuster, and José I. Latorre,

Quantum 4, 226 (2020).

A single qubit provides sufficient computational capabilities to construct a universal quantum classifier when assisted with a classical subroutine. This fact may be surprising since a singl…

Perspective

Contextuality is topological

Shane Mansfield,

Quantum Views 4, 31 (2020).

Contextuality Contextuality is a feature that arises in the empirical predictions of quantum theory, but which cannot arise in classical physics. First identified through the work of Bell [1…

Perspective

Stretching the limits of multiparticle entanglement

Géza Tóth,

Quantum Views 4, 30 (2020).

The classification of entangled mixed states in multiparticle systems is a difficult task. Even for three parties, six classes arise that are inequivalent under Local Operations and Classica…

News

Quantum is hiring another editorial assistant

Quantum continues to grow and is hiring an editorial assistant. For now, this is a part-time position for six months based in Vienna. To learn more have a look at …

Paper

A change of perspective: switching quantum reference frames via a perspective-neutral framework

Augustin Vanrietvelde, Philipp A. Hoehn, Flaminia Giacomini, and Esteban Castro-Ruiz,

Quantum 4, 225 (2020).

Treating reference frames fundamentally as quantum systems is inevitable in quantum gravity and also in quantum foundations once considering laboratories as physical systems. Both fields the…

Perspective

Perspective on: Duality in Quantum Quenches and Classical Approximation Algorithms: Pretty Good or Very Bad

Nicholas Chancellor,

Quantum Views 4, 29 (2020).

This paper examines both a quantum, and highly related quantum inspired algorithm based on an instantaneous quantum quench. Since this algorithm uses a transverse field (single bit flip) dri…

Paper

Quantized Three-Ion-Channel Neuron Model for Neural Action Potentials

Tasio Gonzalez-Raya, Enrique Solano, and Mikel Sanz,

Quantum 4, 224 (2020).

The Hodgkin-Huxley model describes the conduction of the nervous impulse through the axon, whose membrane's electric response can be described employing multiple connected electric circuits…

Paper

From estimation of quantum probabilities to simulation of quantum circuits

Hakop Pashayan, Stephen D. Bartlett, and David Gross,

Quantum 4, 223 (2020).

Investigating the classical simulability of quantum circuits provides a promising avenue towards understanding the computational power of quantum systems. Whether a class of quantum circuits…

Paper

Ideal Projective Measurements Have Infinite Resource Costs

Yelena Guryanova, Nicolai Friis, and Marcus Huber,

Quantum 4, 222 (2020).

We show that it is impossible to perform ideal projective measurements on quantum systems using finite resources. We identify three fundamental features of ideal projective measurements and…

Paper

Quantum algorithms and lower bounds for convex optimization

Shouvanik Chakrabarti, Andrew M. Childs, Tongyang Li, and Xiaodi Wu,

Quantum 4, 221 (2020).

While recent work suggests that quantum computers can speed up the solution of semidefinite programs, little is known about the quantum complexity of more general convex optimization. We pre…

Paper

Convex optimization using quantum oracles

Joran van Apeldoorn, András Gilyén, Sander Gribling, and Ronald de Wolf,

Quantum 4, 220 (2020).

We study to what extent quantum algorithms can speed up solving convex optimization problems. Following the classical literature we assume access to a convex set via various oracles, and we…

Paper

Hypergraph framework for irreducible noncontextuality inequalities from logical proofs of the Kochen-Specker theorem

Ravi Kunjwal,

Quantum 4, 219 (2020).

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 proof of the…