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Related papers: Quantum lower and upper speed limits

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We develop further the approach to upper and lower bounds in quantum dynamics via complex analysis methods which was introduced by us in a sequence of earlier papers. Here we derive upper bounds for non-time averaged outside probabilities…

Spectral Theory · Mathematics 2014-12-30 David Damanik , Serguei Tcheremchantsev

Adiabatic quantum computation is based on the adiabatic evolution of quantum systems. We analyse a particular class of qauntum adiabatic evolutions where either the initial or final Hamiltonian is a one-dimensional projector Hamiltonian on…

Quantum Physics · Physics 2015-05-13 Avatar Tulsi

Geometric phase is a concept of central importance in virtually every branch of physics. In this paper, we show that the evolution time of a cyclically evolving quantum system is restricted by the system's energy resources and the geometric…

Quantum Physics · Physics 2023-12-18 Niklas Hörnedal , Ole Sönnerborn

A theorem of Hegerfeldt shows that if the spectrum of the Hamiltonian is bounded from below, then the propagation speed of certain probabilities does not have an upper bound. We prove a theorem analogous to Hegerfeldt's that appertains to…

Quantum Physics · Physics 2009-11-10 S. Wickramasekara , A. Bohm

The adiabatic theorem provides sufficient conditions for the time needed to prepare a target ground state. While it is possible to prepare a target state much faster with more general quantum annealing protocols, rigorous results beyond the…

Quantum Physics · Physics 2023-11-28 Luis Pedro García-Pintos , Lucas T. Brady , Jacob Bringewatt , Yi-Kai Liu

The "speed" of unitary quantum evolution was recently shown to be connected to entanglement in multipartite quantum systems. Here, we discuss a tighter version of the Mandelstam-Tamm uncertainty relation that depends on the Fisher…

Quantum Physics · Physics 2012-06-01 Florian Fröwis

Quantum algorithms can deliver asymptotic speedups over their classical counterparts. However, there are few cases where a substantial quantum speedup has been worked out in detail for reasonably-sized problems, when compared with the best…

Quantum Physics · Physics 2019-07-24 Earl Campbell , Ankur Khurana , Ashley Montanaro

The question of how fast a quantum state can evolve has attracted a considerable attention in connection with quantum measurement, metrology, and information processing. Since only orthogonal states can be unambiguously distinguished, a…

Quantum Physics · Physics 2015-05-13 Lev B. Levitin , Tommaso Toffoli

We study quantum annealing for combinatorial optimization with Hamiltonian $H = z H_f + H_0$ where $H_f$ is diagonal, $H_0=-|\phi \rangle \langle \phi|$ is the equal superposition state projector and $z$ the annealing parameter. We…

Quantum Physics · Physics 2023-10-24 Aarón Villanueva , Peyman Najafi , Hilbert J. Kappen

We provide a compendium of inequalities between several quantum state distinguishability measures. For each measure these inequalities consist of the sharpest possible upper and lower bounds in terms of another measure. Some of these…

Quantum Physics · Physics 2014-10-24 Koenraad M. R. Audenaert

We revisit key notions related to the evolution of quantum information in few-body quantum mechanics (fbQM) and, for a wide class of dispersion relations, prove uniform bounds on the maximal speed of propagation of quantum information for…

Quantum Physics · Physics 2025-02-28 Israel Michael Sigal , Xiaoxu Wu

We present a simple derivation of the formula for the Hamiltonian operator(s) that achieve the fastest possible unitary evolution between given initial and final states. We discuss how this formula is modified in pseudo-Hermitian quantum…

Quantum Physics · Physics 2009-11-13 Ali Mostafazadeh

Given the initial and final states of a quantum system, the speed of transportation of state vector in the projective Hilbert space governs the quantum speed limit. Here, we ask the question what happens to the quantum speed limit under…

Quantum Physics · Physics 2024-08-16 Abhay Srivastav , Vivek Pandey , Arun K Pati

The Bremermann-Bekenstein bound is a fundamental bound on the maximal rate with which information can be transmitted. However, its derivation relies on rather weak estimates and plausibility arguments, which make the application of the…

Quantum Physics · Physics 2017-06-14 Thiago V. Acconcia , Sebastian Deffner

We perform a comprehensive analysis of the set of parameters $\{r_{i}\}$ that provide the energy distribution of pure qutrits that evolve towards a distinguishable state at a finite time $\tau$, when evolving under an arbitrary and…

Quantum Physics · Physics 2021-07-28 Francisco J. Sevilla , Andrea Valdés-Hernández , Alan J. Barrios

It has recently been shown that small quantum subsystems generically equilibrate, in the sense that they spend most of the time close to a fixed equilibrium state. This relies on just two assumptions: that the state is spread over many…

Quantum Physics · Physics 2015-05-30 Anthony J. Short , Terence C. Farrelly

We give a quantum algorithm for solving instances of the satisfiability problem, based on adiabatic evolution. The evolution of the quantum state is governed by a time-dependent Hamiltonian that interpolates between an initial Hamiltonian,…

Quantum Physics · Physics 2007-05-23 Edward Farhi , Jeffrey Goldstone , Sam Gutmann , Michael Sipser

Quantum Speed Limits (QSLs) rule the minimum time for a quantum state to evolve into a distinguishable state in an arbitrary physical process. These fundamental results constrain a notion of distance travelled by the quantum state, known as…

Quantum Physics · Physics 2021-05-10 Adolfo del Campo

For both unitary and open qubit dynamics, we compare asymmetry monotone-based bounds on the minimal time required for an initial qubit state to evolve to a final qubit state from which it is probabilistically distinguishable with fixed…

Quantum Physics · Physics 2018-10-02 T. J. Volkoff , K. B. Whaley

We derive a family of quantum speed limit results in time independent systems with pure states and a finite dimensional state space, by using a geometric method based on right invariant action functionals on SU(N). The method relates speed…

Quantum Physics · Physics 2014-10-14 Benjamin Russell , Susan Stepney
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