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Related papers: Fast quantum computation at arbitrarily low energy

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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

I report a tight upper bound of the maximum speed of evolution from one quantum state $\rho$ to another $\rho'$ with fidelity $F(\rho,\rho')$ less than or equal to an arbitrary but fixed value under the action of a time-independent…

Quantum Physics · Physics 2013-05-29 H. F. Chau

Cloud-based quantum computers do not provide users with access to hardware-level information such as the underlying Hamiltonians, which obstructs the characterization of their physical properties. We propose a method to infer the energy…

Quantum Physics · Physics 2025-12-18 Nobumasa Ishida , Yoshihiko Hasegawa

Quantum speed limits are rigorous estimates on how fast a state of a quantum system can depart from the initial state in the course of quantum evolution. Most known quantum speed limits, including the celebrated Mandelstam-Tamm and…

Quantum Physics · Physics 2021-06-02 Nikolai Il`in , Oleg Lychkovskiy

Quantum speed limits set the maximal pace of state evolution. Two well-known limits exist for a unitary time-independent Hamiltonian: the Mandelstam-Tamm and Margolus-Levitin bounds. The former restricts the rate according to the state…

Quantum Physics · Physics 2022-10-07 Gal Ness , Andrea Alberti , Yoav Sagi

The Margolus-Levitin (ML) bound says that for any time-independent Hamiltonian, the time needed to evolve from one quantum state to another is at least $\pi \alpha(\epsilon) / (2 \langle E-E_0 \rangle)$, where $\langle E-E_0 \rangle$ is the…

Quantum Physics · Physics 2023-10-06 H. F. Chau

The quantum speed limit indicates the maximal evolution speed of the quantum system. In this work, we determine speed limits on the informational measures, namely the von Neumann entropy, maximal information, and coherence of quantum…

Quantum Physics · Physics 2022-06-16 Brij Mohan , Siddhartha Das , Arun Kumar Pati

The traditional quantum speed limits are not attainable for many physical processes, as they tend to be loose and fail to determine the exact time taken by quantum systems to evolve. To address this, we derive exact quantum speed limits for…

Quantum Physics · Physics 2023-08-30 Arun K. Pati , Brij Mohan , Sahil , Samuel L. Braunstein

In this paper, we derive sharp lower bounds, also known as quantum speed limits, for the time it takes to transform a quantum system into a state such that an observable assumes its lowest average value. We assume that the system is…

Quantum Physics · Physics 2021-06-02 Dan Allan , Niklas Hörnedal , Ole Andersson

We prove fundamental rigorous bounds on the speed of quantum evolution for a quantum system coupled to a thermal bath. The bounds are formulated in terms of expectation values of few-body observables derived from the system-bath…

Quantum Physics · Physics 2024-08-20 N. Il'in , A. Aristova , O. Lychkovskiy

The quantum speed limit is a fundamental concept in quantum mechanics, which aims at finding the minimum time scale or the maximum dynamical speed for some fixed targets. In a large number of studies in this field, the construction of valid…

Quantum Physics · Physics 2020-06-09 Yanyan Shao , Bo Liu , Mao Zhang , Haidong Yuan , Jing Liu

The speed limit provides an upper bound for the dynamical evolution time of a quantum system. Here, we introduce the notion of quantum acceleration limit for unitary time evolution of quantum systems under time-dependent Hamiltonian. We…

Quantum Physics · Physics 2023-12-20 Arun Kumar Pati

Quantum speed limits are the boundaries that define how quickly one quantum state can transform into another. Instead of focusing on the transformation between pairs of states, we provide bounds on the speed limit of quantum evolution by…

Quantum Physics · Physics 2025-11-10 Abolfazl Farmanian , Vahid Karimipour

Quantum speed limits such as the Mandelstam-Tamm or Margolus-Levitin bounds offer a quantitative formulation of the energy-time uncertainty principle that constrains dynamics over short times. We show that the spectral form factor, a…

Quantum Physics · Physics 2024-02-06 Amit Vikram , Victor Galitski

Quantum speed limits provide upper bounds on the rate with which a quantum system can move away from its initial state. Here, we provide a different kind of speed limit, describing the divergence of a perturbed open system from its…

Quantum Physics · Physics 2024-08-28 Benjamin Yadin , Satoya Imai , Otfried Gühne

Over the last few decades, developments in the physical limits of computing and quantum computing have increasingly taught us that it can be helpful to think about physics itself in computational terms. For example, work over the last…

Quantum Physics · Physics 2007-05-23 Michael P. Frank

The quantum speed limit describes how quickly a quantum system can evolve in time from an initial state to a final state under a given dynamics. Here, we derive a generalised quantum speed limit (GQSL) for arbitrary time-continuous…

Quantum Physics · Physics 2023-12-27 Dimpi Thakuria , Abhay Srivastav , Brij Mohan , Asmita Kumari , Arun Kumar Pati

We consider Hamiltonian quantum systems with energy bandwidth \Delta E and show that each measurement that determines the time up to an error \Delta t generates at least the entropy (\hbar/(\Delta t \Delta E))^2/2. Our result describes…

Quantum Physics · Physics 2007-05-23 Dominik Janzing , Thomas Beth

One of the most widely known building blocks of modern physics is Heisenberg's indeterminacy principle. Among the different statements of this fundamental property of the full quantum mechanical nature of physical reality, the uncertainty…

Quantum Physics · Physics 2017-10-17 Sebastian Deffner , Steve Campbell

Quantum speed limit (QSL) is the study of fundamental limits on the evolution time of quantum systems. For instance, under the action of a time-independent Hamiltonian, the evolution time between an initial and a final quantum state obeys…

Quantum Physics · Physics 2024-05-17 H. F. Chau , Wenxin Zeng
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