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Related papers: Non-unitary Time Evolution via the Chebyshev Expan…

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We present a model of discrete quantum evolution based on quantum correlations between the evolving system and a reference quantum clock system. A quantum circuit for the model is provided, which in the case of a constant Hamiltonian is…

Quantum Physics · Physics 2016-07-06 A. Boette , R. Rossignoli , N. Gigena , M. Cerezo

We establish a direct connection between spread complexity and quantum circuit complexity by demonstrating that spread complexity emerges as a limiting case of a circuit complexity framework built from two fundamental operations:…

High Energy Physics - Theory · Physics 2026-05-19 Cameron Beetar , Eric L Graef , Jeff Murugan , Horatiu Nastase , Hendrik J R Van Zyl

In light of recent exciting progress in building up quantum computing facilities based on both optical and cold-atom techniques, the algorithms for quantum simulations of particle-physics systems are in rapid progress. In this paper, we…

High Energy Physics - Phenomenology · Physics 2021-05-12 Ying Chen , Yunheng Ma , Shun Zhou

Feynman's circuit-to-Hamiltonian construction connects quantum computation and ground states of many-body quantum systems. Kitaev applied this construction to demonstrate QMA-completeness of the local Hamiltonian problem, and Aharanov et…

Quantum Physics · Physics 2018-09-28 Johannes Bausch , Elizabeth Crosson

We get the computable error bounds for generalized Cornish-Fisher expansions for quantiles of statistics provided that the computable error bounds for Edgeworth-Chebyshev type expansions for distributions of these statistics are known. The…

Statistics Theory · Mathematics 2017-03-06 V. V. Ulyanov , M. Aoshima , Y. Fujikoshi

Time dependent quantum systems have become indispensable in science and its applications, particularly at the atomic and molecular levels. Here, we discuss the approximation of closed time dependent quantum systems on bounded domains, via…

Analysis of PDEs · Mathematics 2017-09-19 Joseph W. Jerome

Unitary and dissipative models of quantum dynamics are linear maps on the space of states or density matrices. This linearity encodes the superposition principle, a key feature of quantum theory. However, this principle can break down in…

Quantum Physics · Physics 2025-10-31 Orion Lee , Qian Cao , Yogesh N. Joglekar , Kater Murch

We propose a new variational quantum algorithm, which we refer to as TIMES-ADAPT, that prepares time-evolved states in a low-energy or symmetric subspace of a time-independent Hamiltonian on a quantum computer. Using a specially trained…

We consider the problem of learning the evolution operator for the time-dependent Schr\"{o}dinger equation, where the Hamiltonian may vary with time. Existing neural network-based surrogates often ignore fundamental properties of the…

Machine Learning · Statistics 2026-04-07 Yash Patel , Unique Subedi , Ambuj Tewari

The discrete Chebyshev polynomials $t_n(x,N)$ are orthogonal with respect to a distribution function, which is a step function with jumps one unit at the points $x=0,1,..., N-1$, N being a fixed positive integer. By using a double integral…

Classical Analysis and ODEs · Mathematics 2011-10-14 J. H. Pan , R. Wong

Efficient and stable algorithms for the calculation of spectral quantities and correlation functions are some of the key tools in computational condensed matter physics. In this article we review basic properties and recent developments of…

Other Condensed Matter · Physics 2007-05-23 Alexander Weisse , Gerhard Wellein , Andreas Alvermann , Holger Fehske

We present two new quantum algorithms for reaction-diffusion equations that employ the truncated Chebyshev polynomial approximation. This method is employed to numerically solve the ordinary differential equation emerging from the…

Quantum Physics · Physics 2025-10-24 Manish Kumar

We consider a natural dimension reduction technique for the Liouville-von Neumann equation for a mixed quantum system based on evaluation of a trace formula combined with a direct expansion in modified Chebyshev polynomials. This reduction…

Computational Physics · Physics 2010-03-26 Giacomo Mazzi , Ben Leimkuhler

We develop a method for the determination of thecdynamics of dissipative quantum systems in the limit of large number of quanta N, based on the 1/N-expansion of Heidmann et al. [ Opt. Commun. 54, 189 (1985) ] and the quantum-classical…

Quantum Physics · Physics 2009-10-31 Kirill N. Alekseev , Jan Perina

A new numerical method is introduced to study the problem of time evolution of generic non-linear dynamical systems in four-dimensional spacetimes. It is assumed that the time level surfaces are foliated by a one-parameter family of…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Peter Csizmadia , Andras Laszlo , Istvan Racz

The minimal evolution time between two distinguishable states is of fundamental interest in quantum physics. Very recently Mirkin et al. argue that some most common quantum-speed-limit (QSL) bounds which depend on the actual evolution time…

Quantum Physics · Physics 2017-05-31 Xin Liu , Wei Wu , Chao Wang

Realisation of experiments even on small and medium-scale quantum computers requires an optimisation of several parameters to achieve high-fidelity operations. As the size of the quantum register increases, the characterisation of quantum…

Quantum Physics · Physics 2020-08-11 F. Martínez-García , D. Vodola , M. Müller

Time evolution of macroscopic systems is re-examined primarily through further analysis and extension of the equation of motion for the density matrix $\rho(t)$. Because $\rho$ contains both classical and quantum-mechanical probabilities it…

Statistical Mechanics · Physics 2009-11-10 W. T. Grandy

We develop a method for computing the Bogoliubov transformation experienced by a confined quantum scalar field in a globally hyperbolic spacetime, due to the changes in the geometry and/or the confining boundaries. The method constructs a…

Quantum Physics · Physics 2021-10-26 Luis C. Barbado , Ana L. Báez-Camargo , Ivette Fuentes

An analytical solution to the time evolution of decay of one and two identical noninteracting particles is presented using the formalism of resonant states. It is shown that the time-dependent wave function and hence the survival and…

Quantum Physics · Physics 2017-02-20 Gastón García-Calderón