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Related papers: Complexity and Time

200 papers

Chaos and complexity entail an entropic and computational obstruction to describing a system, and thus are intrinsically difficult to characterize. In this paper, we consider time evolution by Gaussian Unitary Ensemble (GUE) Hamiltonians…

High Energy Physics - Theory · Physics 2017-11-16 Jordan Cotler , Nicholas Hunter-Jones , Junyu Liu , Beni Yoshida

We study aspects of black holes and quantum chaos through the behavior of computational costs, which are distance notions in the manifold of unitaries of the theory. To this end, we enlarge Nielsen geometric approach to quantum computation…

High Energy Physics - Theory · Physics 2018-09-26 Javier M. Magan

We define the complexity of a continuous-time linear system to be the minimum number of bits required to describe its forward increments to a desired level of fidelity, and compute this quantity using the rate distortion function of a…

Systems and Control · Electrical Eng. & Systems 2023-06-06 Eric Wendel , John Baillieul , Joseph Hollmann

Computational complexity characterizes the usage of spatial and temporal resources by computational processes. In the classical theory of computation, e.g. in the Turing Machine model, computational processes employ only local space and…

Quantum Physics · Physics 2025-09-25 Chris Fields , James F. Glazebrook , Antonino Marciano , Emanuele Zappala

Performance of cryptanalytic quantum search algorithms is mainly inferred from query complexity which hides overhead induced by an implementation. To shed light on quantitative complexity analysis removing hidden factors, we provide a…

Cryptography and Security · Computer Science 2018-11-02 Panjin Kim , Kyung Chul Jeong , Daewan Han

Motivated by the parametrization invariance of cosmological Lagrangians and their equivalence to systems describing the motion of particles in curved backgrounds, we identify the phase space analogue of the notion of proper time. We define…

General Relativity and Quantum Cosmology · Physics 2025-04-15 N. Dimakis

We show that quantum circuit complexity for the unitary time evolution operator of any time-independent Hamiltonian is bounded by linear growth at early times, independent of any choices of the fundamental gates or cost metric. Deviations…

High Energy Physics - Theory · Physics 2024-10-15 S. Shajidul Haque , Ghadir Jafari , Bret Underwood

There are at least a number of ways to formally define complexity. Most of them relate to some kind of minimal description of the studied object. Being this one in form of minimal resources of minimal effort needed to generate the object…

Quantum Physics · Physics 2013-04-25 Yuri Campbell , José Roberto Castilho Piqueira

In this talk we entertain the possibility that the synthesis of general covariance and quantum mechanics requires an extension of the basic kinematical setup of quantum mechanics. According to the holographic principle, regions of spacetime…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Vijay Balasubramanian , Jan de Boer , Djordje Minic

I discuss several aspects of information theory and its relationship to physics and neuroscience. The unifying thread of this somewhat chaotic essay is the concept of Kolmogorov or algorithmic complexity (Kolmogorov Complexity, for short).…

General Physics · Physics 2007-05-23 Giulio Ruffini

We study the relation between quantum computational complexity and general relativity. The quantum computational complexity is proposed to be quantified by the shortest length of geodesic quantum curves. We examine the complexity/volume…

High Energy Physics - Theory · Physics 2018-03-14 Xian-Hui Ge , Bin Wang

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

This paper considers the realizability of quantum gates from the perspective of information complexity. Since the gate is a physical device that must be controlled classically, it is subject to random error. We define the complexity of gate…

Quantum Physics · Physics 2009-11-11 Subhash Kak

We provide the most general forms of covariant and normalized time operators and their probability densities, with applications to quantum clocks, the time of arrival, and Lyapunov quantum operators. Examples are discussed of the profusion…

Quantum Physics · Physics 2015-05-19 G. C. Hegerfeldt , J. G. Muga , J. Muñoz

We propose a new approach for multiverse analysis based on computational complexity, which leads to a new family of "computational" measure factors. By defining a cosmology as a space-time containing a vacuum with specified properties (for…

High Energy Physics - Theory · Physics 2018-04-18 Frederik Denef , Michael R. Douglas , Brian Greene , Claire Zukowski

Quantum circuit complexity has played a central role in recent advances in holography and many-body physics. Within quantum field theory, it has typically been studied in a Lorentzian (real-time) framework. In a departure from standard…

High Energy Physics - Theory · Physics 2022-10-12 Josiah Couch , Yale Fan , Sanjit Shashi

We argue that the complex numbers are an irreducible object of quantum probability. This can be seen in the measurements of geometric phases that have no classical probabilistic analogue. Having complex phases as primitive ingredient…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Charis Anastopoulos

Perturbation theory in quantum mechanics studies how quantum systems interact with their environmental perturbations. Harmonic perturbation is a rare special case of time-dependent perturbations in which exact analysis exists. Some…

Quantum Physics · Physics 2008-01-01 Jie-Hong R. Jiang , Dah-Wei Chiou , Cheng-En Wu

Given a quantum Hamiltonian and its evolution time, the corresponding unitary evolution operator can be constructed in many different ways, corresponding to different trajectories between the desired end-points. A choice among these…

Quantum Physics · Physics 2015-03-05 Apoorva Patel

Quantum computation with quantum data that can traverse closed timelike curves represents a new physical model of computation. We argue that a model of quantum computation in the presence of closed timelike curves can be formulated which…

Quantum Physics · Physics 2008-11-26 Dave Bacon