English
Related papers

Related papers: Deutschian closed timelike curves can create entan…

200 papers

Recent advances have led towards first prototypes of quantum networks in which entanglement is distributed by sources producing bipartite entangled states. This raises the question of which states can be generated in quantum networks based…

Quantum Physics · Physics 2024-03-14 Cornelia Spee , Tristan Kraft

We consider generic pure $n$-qubit states and a general class of pure states of arbitrary dimensions and arbitrarily many subsystems. We characterize those states which can be reached from some other state via Local Operations assisted by…

Quantum Physics · Physics 2017-02-01 C. Spee , J. I. de Vicente , D. Sauerwein , B. Kraus

Quantum correlations are at the heart of many applications in quantum information science and, at the same time, they form the basis for discussions about genuine quantum effects and their difference to classical physics. On one hand,…

Quantum Physics · Physics 2014-08-06 Tobias Moroder , Oleg Gittsovich , Marcus Huber , Otfried Gühne

Boundary time crystals (BTCs) break time-translation symmetry and exhibit long-lived, robust oscillations insensitive to initial conditions. We show that collective spin BTCs can admit emergent topological winding numbers in operator space.…

Quantum Physics · Physics 2026-02-23 Dominik Nemeth , Ahsan Nazir , Alessandro Principi , Robert-Jan Slager

The problem behind this paper is, if the number of queries to unitary operations is fixed, say $k$, then when do local operations and classical communication (LOCC) suffice for optimally distinguishing bipartite unitary operations? We…

Quantum Physics · Physics 2017-12-06 Lvzhou Li , Shenggen Zheng , Haozhen Situ , Daowen Qiu

The generation of long-lived entanglement on an optical clock transition is a key requirement to unlocking the promise of quantum metrology. Arrays of neutral atoms constitute a capable quantum platform for accessing such physics, where…

Atomic Physics · Physics 2022-08-12 Nathan Schine , Aaron W. Young , William J. Eckner , Michael J. Martin , Adam M. Kaufman

We show that a set of linearly independent quantum states $\{(U_{m,n}\otimes I)\rho ^{AB}(U_{m,n}^{\dagger}\otimes I)\}_{m,n=0}^{d-1}$, where $U_{m,n}$ are generalized Pauli matrices, cannot be discriminated deterministically or…

Quantum Physics · Physics 2009-11-10 Heng Fan

It is known that there exist non-local correlations that respect no-signaling criterion, but violate Bell-type inequalities more than quantum-mechanical correlations. Such super quantum correlations were introduced as the Popescu-Rohrlich…

Quantum Physics · Physics 2014-12-15 Indranil Chakrabarty , Tanumoy Pramanik , Arun K Pati , Pankaj Agrawal

We investigate the discrete time crystal (DTC) phase in a qubit ensemble, periodically driven by its interaction with either a photon or a transmon field, which is prone to dissipative leakage. We find this DTC to be robust against changes…

Quantum Physics · Physics 2024-07-09 Tanaya Ray , Shuva Mondal , Ujjwal Sen

Many solutions of Einstein's field equations contain closed timelike curves (CTC). Some of these solutions refer to ordinary materials in situations which might occur in the laboratory, or in astrophysics. It is argued that, in default of a…

General Relativity and Quantum Cosmology · Physics 2009-11-07 W. B. Bonnor

Decoherence is one of the main obstacles in long-distance quantum communication. Recently, the theoretical work of Fr\"{o}wis and W. D\"{u}r (Phys. Rev. Lett. \textbf{106}, 110402 (2011)) and the experiment of Lu \emph{et al.} (Nat. Photon.…

Quantum Physics · Physics 2014-05-13 Yu-Bo Sheng , Lan Zhou

We studied pure state transformations using local operations assisted by finitely many rounds of classical communication ($LOCC_{\mathbb{N}}$) in C. Spee, J.I. de Vicente, D. Sauerwein, B. Kraus, arXiv:1606.04418 (2016). Here, we first of…

Quantum Physics · Physics 2017-02-01 J. I. de Vicente , C. Spee , D. Sauerwein , B. Kraus

In this study, we establish a connection between timelike and spacelike entanglement entropy. We show that timelike entanglement entropy is closely related to spacelike entanglement entropy and its temporal derivative. For a broad class of…

High Energy Physics - Theory · Physics 2026-01-01 Wu-zhong Guo , Song He , Yu-Xuan Zhang

In general relativity, closed timelike curves can break causality with remarkable and unsettling consequences. At the classical level, they induce causal paradoxes disturbing enough to motivate conjectures that explicitly prevent their…

We construct a metrology experiment in which the metrologist can sometimes amend her input state by simulating a closed timelike curve, a worldline that travels backward in time. The existence of closed timelike curves is hypothetical.…

Quantum Physics · Physics 2023-11-07 David R. M. Arvidsson-Shukur , Aidan G. McConnell , Nicole Yunger Halpern

Hance and Hossenfelder recently claim that the extensive experimental confirmations of Bell's Theorem do not in fact demonstrate that nature is nonlocal, but merely that nature can be local only if the distant detector settings in a…

General Physics · Physics 2024-10-10 Kent A. Peacock

We consider one single copy of a mixed state of two qubits and investigate how its entanglement changes under local quantum operations and classical communications (LQCC) of the type $\rho'\sim (A\otimes B)\rho(A\otimes B)^{\dagger}$. We…

Quantum Physics · Physics 2009-11-06 Frank Verstraete , Jeroen Dehaene , Bart De Moor

We show that entanglement guarantees difficulty in the discrimination of orthogonal multipartite states locally. The number of pure states that can be discriminated by local operations and classical communication is bounded by the total…

Quantum Physics · Physics 2009-11-11 M. Hayashi , D. Markham , M. Murao , M. Owari , S. Virmani

We use an alternative approach to show that quantum entanglement-like correlations cannot be reproduced for any classical protocol. In our proposal, quantum geometric restrictions are impose over the physical system related to the existence…

Quantum Physics · Physics 2018-09-12 R. Restrepo-Villegas , E. Agudelo , J. Castrillón , B. A. Rodríguez

A discrete time crystal (DTC) is the paradigmatic example of a phase of matter that occurs exclusively in systems out of equilibrium. This phenomenon is characterized by the spontaneous symmetry breaking of discrete time-translation and…