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Related papers: Renormalization and Coarse-graining of Loop Quantu…

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Coarse-graining has become an area of tremendous importance within many different research fields. For molecular simulation, coarse-graining bears the promise of finding simplified models such that long-time simulations of large-scale…

Chemical Physics · Physics 2019-09-04 Feliks Nüske , Lorenzo Boninsegna , Cecilia Clementi

In this paper we point out some possible links between different approaches to quantum gravity and theories of the Planck scale physics. In particular, connections between Loop Quantum Gravity, Causal Dynamical Triangulations,…

High Energy Physics - Theory · Physics 2018-05-28 Jakub Mielczarek , Tomasz Trześniewski

We define a class of quantum systems called regular quantum graphs. Although their dynamics is chaotic in the classical limit with positive topological entropy, the spectrum of regular quantum graphs is explicitly computable analytically…

Quantum Physics · Physics 2007-05-23 R. Blümel , Yu. Dabaghian , R. V. Jensen

The choice of the regularization scheme in Loop Quantum Cosmology (LQC) is crucial for the predicted phenomenology. We outline how the improved scheme can be naturally realized in Quantum Reduced Loop Gravity, describing the Universe as an…

General Relativity and Quantum Cosmology · Physics 2016-04-11 Emanuele Alesci , Francesco Cianfrani

Recent years have witnessed rapid advances in graph representation learning, with the continuous embedding approach emerging as the dominant paradigm. However, such methods encounter issues regarding parameter efficiency, interpretability,…

Machine Learning · Computer Science 2026-01-22 Qika Lin , Zhen Peng , Kaize Shi , Kai He , Yiming Xu , Jian Zhang , Erik Cambria , Mengling Feng

We review the techniques used to renormalize quantum field theories at several loop orders. This includes the techniques to systematically extract the infinities in a Feynman integral and the implementation of the algorithm within computer…

High Energy Physics - Theory · Physics 2007-05-23 J. A. Gracey

We propose and illustrate an approach to coarse-graining the dynamics of evolving networks (networks whose connectivity changes dynamically). The approach is based on the equation-free framework: short bursts of detailed network evolution…

Social and Information Networks · Computer Science 2012-02-28 Katherine A. Bold , Karthikeyan Rajendran , Balázs Ráth , Ioannis G. Kevrekidis

The origin of classical predictability is investigated for the one dimensional harmonic chain considered as a closed quantum mechanical system. By comparing the properties of a family of coarse-grained descriptions of the chain, we conclude…

Quantum Physics · Physics 2009-10-31 Todd A. Brun , James B. Hartle

Loop quantum gravity is an approach to quantum gravity that starts from the Hamiltonian formulation in terms of a connection and its canonical conjugate. Quantization proceeds in the spirit of Dirac: First one defines an algebra of basic…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Jerzy Lewandowski , Andrzej Okolow , Hanno Sahlmann , Thomas Thiemann

We study two-dimensional quantum gravity on arbitrary genus Riemann surfaces in the Kaehler formalism where the basic quantum field is the (Laplacian of the) Kaehler potential. We do a careful first-principles computation of the fixed-area…

High Energy Physics - Theory · Physics 2015-12-09 Adel Bilal , Laetitia Leduc

To understand the dynamics of loop quantum gravity, the deparametrized model of gravity coupled to a scalar field is studied in a simple case, where the graph underlying the spin network basis is one loop based at a single vertex. The…

General Relativity and Quantum Cosmology · Physics 2019-06-20 Cong Zhang , Jerzy Lewandowski , Haida Li , Yongge Ma

The general method of graph coarsening or graph reduction has been a remarkably useful and ubiquitous tool in scientific computing and it is now just starting to have a similar impact in machine learning. The goal of this paper is to take a…

Machine Learning · Computer Science 2021-06-23 Jie Chen , Yousef Saad , Zechen Zhang

Quantum theory has shown its superiority in enhancing machine learning. However, facilitating quantum theory to enhance graph learning is in its infancy. This survey investigates the current advances in quantum graph learning (QGL) from…

Machine Learning · Computer Science 2023-02-03 Shuo Yu , Ciyuan Peng , Yingbo Wang , Ahsan Shehzad , Feng Xia , Edwin R. Hancock

A coarse graining operation of spatially homogeneous quantum states based on an SU(1,1) Lie group structure has recently been proposed in [1] and used in [2] to compute an explicit renormalisation group flow in the context of loop quantum…

General Relativity and Quantum Cosmology · Physics 2021-07-07 Norbert Bodendorfer , Fabian Haneder

In this PhD thesis, we introduced a new strategy to investigate the kinematical and physical predictions of self dual Loop Quantum Gravity (LQG) and by-passed the old problem of implementing quantum mechanically the so called reality…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Jibril Ben Achour

A first step towards implementing a notion of coarse graining in an intrinsically Lorentzian, discrete quantum- gravity approach, namely causal set quantum gravity is taken. It makes use of an abstract notion of scale, based on counting the…

General Relativity and Quantum Cosmology · Physics 2018-02-14 Astrid Eichhorn

In this thesis, we focus on higher-curvature extensions of Einstein gravity as toy models to probe universal properties of conformal field theory (CFT) using the gauge/gravity duality. In this context, we are particularly interested in…

High Energy Physics - Theory · Physics 2022-07-27 Javier Moreno

Continual learning on graphs tackles the problem of training a graph neural network (GNN) where graph data arrive in a streaming fashion and the model tends to forget knowledge from previous tasks when updating with new data. Traditional…

Machine Learning · Computer Science 2024-01-09 Xiaoxue Han , Zhuo Feng , Yue Ning

We define a modification of LQG in which graphs are required to consist in piecewise linear edges, which we call piecewise linear LQG (plLQG). At the diffeomorphism invariant level, we prove that plLQG is equivalent to standard LQG, as long…

General Relativity and Quantum Cosmology · Physics 2010-01-21 Jonathan Engle

The dynamical cluster approximation (DCA) and its DCA$^+$ extension use coarse-graining of the momentum space to reduce the complexity of quantum many-body problems, thereby mapping the bulk lattice to a cluster embedded in a dynamical…

Strongly Correlated Electrons · Physics 2016-05-04 P. Staar , M. Jiang , U. R. Hähner , T. C. S. Schulthess , T. A. Maier