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It is remarkable that Heisenberg's position-momentum uncertainty relation leads to the existence of a maximal acceleration for a physical particle in the context of a geometric reformulation of quantum mechanics. It is also known that the…

Quantum Physics · Physics 2024-09-05 Paul M. Alsing , Carlo Cafaro

A quantum search algorithm based on the partial adiabatic evolution\cite{Tulsi2009} is provided. We calculate its time complexity by studying the Hamiltonian in a two-dimensional Hilbert space. It is found that the algorithm improves the…

Data Structures and Algorithms · Computer Science 2015-05-19 Ying-Yu Zhang , Song-Feng Lu

Loop Quantum Gravity faces challenges in constructing a well-defined Hamiltonian constraint and understanding the quantum notion of time. In this paper these issues are studied by quantizing the $U(1)^3$ model, a simplified system…

General Relativity and Quantum Cosmology · Physics 2024-12-02 Sepideh Bakhoda , Yongge Ma

For chaotic quantum dynamics modeled by random unitary circuits, we study the complexity of reduced density matrices of subsystems as a function of evolution time where the initial global state is a product pure state. The state complexity…

Quantum Physics · Physics 2026-04-30 Jeongwan Haah , Douglas Stanford

We construct a formalism for evolving spherically symmetric black hole initial data sets within a canonical approach to quantum gravity. This problem can be formulated precisely in quantum reduced loop gravity, a framework which has been…

General Relativity and Quantum Cosmology · Physics 2019-09-13 Emanuele Alesci , Sina Bahrami , Daniele Pranzetti

We describe a method to simulate Hamiltonian evolution on a quantum computer by repeatedly using a superposition of steps of a quantum walk, then applying a correction to the weightings for the numbers of steps of the quantum walk. This…

Quantum Physics · Physics 2017-02-15 Dominic W. Berry , Leonardo Novo

The attempt to gain a theoretical understanding of the concept of time in quantum mechanics has triggered significant progress towards the search for faster and more efficient quantum technologies. One of such advances consists in the…

A central feature of quantum mechanics is that a measurement is intrinsically probabilistic. As a result, continuously monitoring a quantum system will randomly perturb its natural unitary evolution. The ability to control a quantum system…

Quantum Physics · Physics 2014-09-04 S. J. Weber , A. Chantasri , J. Dressel , A. N. Jordan , K. W. Murch , I. Siddiqi

The "quantum complexity" of a unitary operator measures the difficulty of its construction from a set of elementary quantum gates. While the notion of quantum complexity was first introduced as a quantum generalization of the classical…

Quantum Physics · Physics 2021-11-02 Vir B. Bulchandani , S. L. Sondhi

We investigate the sensing capacity of non-equilibrium dynamics in quantum systems exhibiting Bloch oscillations. By focusing on the resource efficiency of the probe, quantified by quantum Fisher information, we find different scaling…

Quantum Physics · Physics 2025-07-16 Hassan Manshouri , Moslem Zarei , Mehdi Abdi , Sougato Bose , Abolfazl Bayat

The complexity of the quantum state of a multiparticle system and the maximum possible accuracy of its quantum description are connected by a relation similar to the coordinate-momentum uncertainty relation. The coefficient in this relation…

Quantum Physics · Physics 2021-10-01 Yuri I. Ozhigov

We investigate notions of complexity of states in continuous quantum-many body systems. We focus on Gaussian states which include ground states of free quantum field theories and their approximations encountered in the context of the…

High Energy Physics - Theory · Physics 2018-11-15 Shira Chapman , Michal P. Heller , Hugo Marrochio , Fernando Pastawski

By using an exact solution to the time-dependent Schr\"{o}dinger equation with a point source initial condition, we investigate both the time and spatial dependence of quantum waves in a step potential barrier. We find that for a source…

Quantum Physics · Physics 2009-11-07 Jorge Villavicencio , Roberto Romo , Sukey Sosa y Silva

With the growth of geometric science, including the methods of exploring the world of information by means of modern geometry, there has always been a mysterious and fascinating ambiguous link between geometric, topological and dynamical…

Quantum Physics · Physics 2024-09-04 Jamal Elfakir , Brahim Amghar , Abdallah Slaoui , Mohammed Daoud

We study characteristics of quantum evolution which can be called curvature and torsion. The curvature shows a deviation of the state vector in quantum evolution from the geodesic line. The torsion shows a deviation of state vector from the…

Quantum Physics · Physics 2017-04-03 H. P. Laba , V. M. Tkachuk

We study time evolution of a subsystem's density matrix under unitary evolution, generated by a sufficiently complex, say quantum chaotic, Hamiltonian, modeled by a random matrix. We exactly calculate all coherences, purity and…

Quantum Physics · Physics 2012-03-15 Vinayak , Marko Znidaric

The problem of the time of arrival of a quantum system in a specified state is considered in the framework of the repeated measurement protocol and in particular the limit of continuous measurements is discussed. It is shown that for a…

Quantum Physics · Physics 2021-04-07 Varun Dubey , Cedric Bernardin , Abhishek Dhar

We study the temporal evolution of the circuit complexity for a subsystem in harmonic lattices after a global quantum quench of the mass parameter, choosing the initial reduced density matrix as the reference state. Upper and lower bounds…

High Energy Physics - Theory · Physics 2021-05-13 Giuseppe Di Giulio , Erik Tonni

The speed of quantum evolution is limited under finite energy resources. While most quantum speed limits (QSLs) are formulated in terms of quantum states, they can be extended to the evolution operator itself, and thus impose fundamental…

Quantum Physics · Physics 2026-04-28 Hunter Nelson , Edwin Barnes

Quantum simulation using time evolution in phase estimation-based quantum algorithms can yield unbiased solutions of classically intractable models. However, long runtimes open such algorithms to decoherence. We show how measurement-based…

Quantum Physics · Physics 2022-08-11 Woo-Ram Lee , Zhangjie Qin , Robert Raussendorf , Eran Sela , V. W. Scarola