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Related papers: Geometry of quantum complexity

200 papers

As a new step towards defining complexity for quantum field theories, we map Nielsen operator complexity for $SU(N)$ gates to two-dimensional hydrodynamics. We develop a tractable large $N$ limit that leads to regular geometries on the…

High Energy Physics - Theory · Physics 2022-10-05 Pablo Basteiro , Johanna Erdmenger , Pascal Fries , Florian Goth , Ioannis Matthaiakakis , René Meyer

Conventional quantum computing entails a geometry based on the description of an n-qubit state using 2^{n} infinite precision complex numbers denoting a vector in a Hilbert space. Such numbers are in general uncomputable using any…

Quantum Physics · Physics 2015-06-05 Andrew J. Hanson , Gerardo Ortiz , Amr Sabry , Yu-Tsung Tai

Quantum complexity measures the difficulty of obtaining a given state starting from a typically unentangled state. In this work, we show that complexity, when defined through the minimization of a Riemannian cost functional over the…

Quantum Physics · Physics 2025-06-05 Nadir Samos Sáenz de Buruaga

A new functional calculus, developed recently for a fully non-perturbative treatment of quantum gravity, is used to begin a systematic construction of a quantum theory of geometry. Regulated operators corresponding to areas of 2-surfaces…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Abhay Ashtekar , Jerzy Lewandowski

We define the algorithmic complexity of a quantum state relative to a given precision parameter, and give upper bounds for various examples of states. We also establish a connection between the entanglement of a quantum state and its…

Quantum Physics · Physics 2009-11-11 Caterina Mora , Hans Briegel

In Nielsen's geometric approach to quantum complexity, the introduction of a suitable geometrical space, based on the Lie group formed by fundamental operators, facilitates the identification of complexity through geodesic distance in the…

Quantum Physics · Physics 2025-04-03 Satyaki Chowdhury , Martin Bojowald , Jakub Mielczarek

In physics, two systems that radically differ at short scales can exhibit strikingly similar macroscopic behaviour: they are part of the same long-distance universality class. Here we apply this viewpoint to geometry and initiate a program…

High Energy Physics - Theory · Physics 2023-11-22 Adam R. Brown , Michael H. Freedman , Henry W. Lin , Leonard Susskind

This paper proposes a method of unifying quantum mechanics and gravity based on quantum computation. In this theory, fundamental processes are described in terms of pairwise interactions between quantum degrees of freedom. The geometry of…

Quantum Physics · Physics 2018-04-11 Seth Lloyd

Geometric quantum mechanics, through its differential-geometric underpinning, provides additional tools of analysis and interpretation that bring quantum mechanics closer to classical mechanics: state spaces in both are equipped with…

Quantum Physics · Physics 2024-05-08 Fabio Anza , James P. Crutchfield

An important conjecture within the AdS/CFT correspondence relates holographic spacetime to the quantum computational complexity of the dual quantum field theory. However, the quantitative understanding of this relation is still an open…

High Energy Physics - Theory · Physics 2022-12-02 Johanna Erdmenger , Marius Gerbershagen , Michal P. Heller , Anna-Lena Weigel

The Hilbert space formalism of quantum mechanics is reviewed with emphasis on applications to quantum computing. Standard interferomeric techniques are used to construct a physical device capable of universal quantum computation. Some…

High Energy Physics - Theory · Physics 2007-05-23 K. Svozil

Black Holes have always played a central role in investigations of quantum gravity. This includes both conceptual issues such as the role of classical singularities and information loss, and technical ones to probe the consistency of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Martin Bojowald

This paper develops a geometric model for coupled two-state quantum systems (qubits), which is formulated using geometric (aka Clifford) algebra. It begins by showing how Euclidean spinors can be interpreted as entities in the geometric…

Quantum Physics · Physics 2007-05-23 Timothy F. Havel , Chris J. L. Doran

Determining the quantum circuit complexity of a unitary operation is closely related to the problem of finding minimal length paths in a particular curved geometry [Nielsen et al, Science 311, 1133-1135 (2006)]. This paper investigates many…

Quantum Physics · Physics 2007-05-23 Mark R. Dowling , Michael A. Nielsen

For any quantum algorithm given by a path in the space of unitary operators we define the computational complexity as the typical computational time associated with the path. This time is defined using a quantum time estimator associated…

High Energy Physics - Theory · Physics 2020-04-01 Cesar Gomez

The basic idea of quantum complexity geometry is to endow the space of unitary matrices with a metric, engineered to make complex operators far from the origin, and simple operators near. By restricting our attention to a finite subgroup of…

High Energy Physics - Theory · Physics 2019-02-20 Henry W. Lin

Over the past six years, a detailed framework has been constructed to unravel the quantum nature of the Riemannian geometry of physical space. A review of these developments is presented at a level which should be accessible to graduate…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Abhay Ashtekar

Quantum algorithms are sequences of abstract operations, performed on non-existent computers. They are in obvious need of categorical semantics. We present some steps in this direction, following earlier contributions of Abramsky, Coecke…

Quantum Physics · Physics 2016-11-09 Dusko Pavlovic

Using a recently developed quantization of spherically symmetric gravity coupled to a scalar field, we give a construction of null expansion operators that allow a definition of general, fully dynamical quantum black holes. These operators…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Viqar Husain , Oliver Winkler

We summarize our work on spherically symmetric midi-superspaces in loop quantum gravity. Our approach is based on using inhomogeneous slicings that may penetrate the horizon in case there is one and on a redefinition of the constraints so…

General Relativity and Quantum Cosmology · Physics 2025-05-14 Rodolfo Gambini , Javier Olmedo , Jorge Pullin