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Related papers: Quantum Natural Gradient

200 papers

Consider the following distributed optimization scenario. A worker has access to training data that it uses to compute the gradients while a server decides when to stop iterative computation based on its target accuracy or delay…

Machine Learning · Computer Science 2022-04-28 Chung-Yi Lin , Victoria Kostina , Babak Hassibi

Many machine learning problems can be expressed as the optimization of some cost functional over a parametric family of probability distributions. It is often beneficial to solve such optimization problems using natural gradient methods.…

Machine Learning · Statistics 2020-02-14 Michael Arbel , Arthur Gretton , Wuchen Li , Guido Montufar

Accelerating the convergence of second-order optimization, particularly Newton-type methods, remains a pivotal challenge in algorithmic research. In this paper, we extend previous work on the \textbf{Quadratic Gradient (QG)} and rigorously…

Optimization and Control · Mathematics 2026-04-01 John Chiang

The quantum geometric tensor (QGT) fundamentally encodes the geometry and topology of quantum states in both Hermitian and non-Hermitian regimes. While adiabatic perturbation theory links its real part (quantum metric) and imaginary part…

Quantum Physics · Physics 2025-12-19 Ze-Hao Huang , Hai-Tao Ding , Li-Jun Lang

A quantum trajectory describes the evolution of a quantum system undergoing indirect measurement. In the discrete-time setting, the state of the system is updated by applying Kraus operators according to the measurement results. From an…

Quantum Physics · Physics 2022-04-04 Maël Bompais , Nina H. Amini , Clément Pellegrini

We construct a classical algorithm that designs quantum circuits for algorithmic quantum simulation of arbitrary qudit channels on fault-tolerant quantum computers within a pre-specified error tolerance with respect to diamond-norm…

Quantum Physics · Physics 2015-09-23 Dong-Sheng Wang , Barry C. Sanders

Thermal states play a fundamental role in various areas of physics, and they are becoming increasingly important in quantum information science, with applications related to semi-definite programming, quantum Boltzmann machine learning,…

Quantum Physics · Physics 2025-11-13 Dhrumil Patel , Mark M. Wilde

Quantum simulation has begun to penetrate the field of quantum chemistry in hopes of efficiently calculating ground state energies and approximating real-time evolution. With modern research highlighting nonadiabatic dynamics, tunably…

Quantum Physics · Physics 2026-05-08 Joshua M. Courtney , P. C. Stancil

We put forward a strategy to encode a quantum operation into the unmodulated dynamics of a quantum network without the need of external control pulses, measurements or active feedback. Our optimization scheme, inspired by supervised machine…

Quantum Physics · Physics 2016-07-21 Leonardo Banchi , Nicola Pancotti , Sougato Bose

Quantum machine learning and optimization are exciting new areas that have been brought forward by the breakthrough quantum algorithm of Harrow, Hassidim and Lloyd for solving systems of linear equations. The utility of {classical} linear…

Quantum Physics · Physics 2021-03-02 Iordanis Kerenidis , Anupam Prakash

Gradient-based optimization is a key ingredient of variational quantum algorithms, with applications ranging from quantum machine learning to quantum chemistry and simulation. The parameter-shift rule provides a hardware-friendly method for…

Quantum Physics · Physics 2025-10-08 Leonardo Banchi , Dominic Branford , Chetan Waghela

The description of a closed quantum system is extended with the identification of an underlying substructure enabling an expanded formulation of dynamics in the Heisenberg picture. Between measurements a ``state point" moves in an…

Quantum Physics · Physics 2026-01-21 Anthony John Bracken

The geometry of Hamiltonian's eigenstates is encoded in the quantum geometric tensor (QGT). It contains both the Berry curvature, central to the description of topological matter and the quantum metric. So far the full QGT has been measured…

Mesoscale and Nanoscale Physics · Physics 2021-09-08 Qing Liao , Charly Leblanc , Jiahuan Ren , Feng Li , Yiming Li , Dmitry Solnyshkov , Guillaume Malpuech , Jiannian Yao , Hongbing Fu

Quantum optimal control theory (QOCT) aims at finding an external field that drives a quantum system in such a way that optimally achieves some predefined target. In practice this normally means optimizing the value of some observable, a so…

Quantum Physics · Physics 2011-09-19 Alberto Castro , I. V. Tokatly

The quantum geometric tensor (QGT) is a fundamental concept for characterizing the local geometry of quantum states. After casting the geometry of pure quantum states and extracting the QGT, we generalize the geometry to mixed quantum…

Quantum Physics · Physics 2024-07-19 Xu-Yang Hou , Zheng Zhou , Xin Wang , Hao Guo , Chih-Chun Chien

Many experimental proposals for noisy intermediate scale quantum devices involve training a parameterized quantum circuit with a classical optimization loop. Such hybrid quantum-classical algorithms are popular for applications in quantum…

Quantum Physics · Physics 2019-02-04 Jarrod R. McClean , Sergio Boixo , Vadim N. Smelyanskiy , Ryan Babbush , Hartmut Neven

We discuss a Quantum Non-Demolition Measurement (QNDM) protocol to estimate the derivatives of a cost function with a quantum computer. %This is a key step for the implementation of variational quantum circuits. The cost function, which is…

Quantum Physics · Physics 2023-06-07 Paolo Solinas , Simone Caletti , Giovanni Minuto

We consider a generic framework of optimization algorithms based on gradient descent. We develop a quantum algorithm that computes the gradient of a multi-variate real-valued function $f:\mathbb{R}^d\rightarrow \mathbb{R}$ by evaluating it…

Quantum Physics · Physics 2019-02-19 András Gilyén , Srinivasan Arunachalam , Nathan Wiebe

Variational quantum circuits are used in quantum machine learning and variational quantum simulation tasks. Designing good variational circuits or predicting how well they perform for given learning or optimization tasks is still unclear.…

Quantum Physics · Physics 2022-08-18 Junyu Liu , Francesco Tacchino , Jennifer R. Glick , Liang Jiang , Antonio Mezzacapo

In this paper, we discuss a geometrodynamical approach to particle physics, in which quantum mechanics is no more than an approximated model of nature in the microscopic scale. We derive quantum mechanics from the concept of non-local…

General Relativity and Quantum Cosmology · Physics 2020-02-05 Tomer Shushi