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Related papers: Coarse graining flow of spin foam intertwiners

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We study the predictability of emergent phenomena in complex systems. Using nearest neighbor, one-dimensional Cellular Automata (CA) as an example, we show how to construct local coarse-grained descriptions of CA in all classes of Wolfram's…

Cellular Automata and Lattice Gases · Physics 2015-06-26 Navot Israeli , Nigel Goldenfeld

The asymptotics of some spin foam amplitudes for a quantum 4-simplex is known to display rapid oscillations whose frequency is the Regge action. In this note, we reformulate this result through a difference equation, asymptotically…

General Relativity and Quantum Cosmology · Physics 2011-08-09 Valentin Bonzom

This paper explores the potential of Physics-Informed Neural Networks (PINNs) to serve as Reduced Order Models (ROMs) for simulating the flow field within stirred tank reactors (STRs). We solve the two-dimensional stationary Navier-Stokes…

Computational Engineering, Finance, and Science · Computer Science 2025-07-16 Veronika Trávníková , Daniel Wolff , Nico Dirkes , Stefanie Elgeti , Eric von Lieres , Marek Behr

Coarse-grained models are a core computational tool in theoretical chemistry and biophysics. A judicious choice of a coarse-grained model can yield physical insight by isolating the essential degrees of freedom that dictate the…

Statistical Mechanics · Physics 2023-04-12 Shriram Chennakesavalu , David J. Toomer , Grant M. Rotskoff

We present a new approach to coarse-graining of variables describing dust flow in GR. It is based on assigning quasi-local shear, twist and expansion to 2-dimensional surfaces with the help of isometric embeddings into the 3-dimensional…

General Relativity and Quantum Cosmology · Physics 2015-05-14 Mikolaj Korzynski

Coarse graining model is a promising way to analyze and visualize large-scale networks. The coarse-grained networks are required to preserve the same statistical properties as well as the dynamic behaviors as the initial networks. Some…

Physics and Society · Physics 2011-05-31 An Zeng , Linyuan Lu

We simulate the two-dimensional XY model in the flow representation by a worm-type algorithm, up to linear system size $L=4096$, and study the geometric properties of the flow configurations. As the coupling strength $K$ increases, we…

Statistical Mechanics · Physics 2021-06-30 Bao-Zong Wang , Pengcheng Hou , Chun-Jiong Huang , Youjin Deng

Electrostatic interactions between macroions largely govern the equilibrium thermodynamic and dynamical properties of charge-stabilized colloidal suspensions and polyelectrolyte solutions. Predicting the properties of such complex,…

Soft Condensed Matter · Physics 2012-12-11 Alan R. Denton

We develop coarse-grained particle approaches for studying the elastic mechanics of vesicles with heterogeneous membranes having phase-separated domains. We perform simulations both of passive shape fluctuations and of active systems where…

Soft Condensed Matter · Physics 2023-02-28 David A. Rower , Paul J. Atzberger

We discuss various features and details of two versions of the Barrett-Crane spin foam model of quantum gravity, first of the Spin(4)-symmetric Riemannian model and second of the SL(2,C)-symmetric Lorentzian version in which all tetrahedra…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hendryk Pfeiffer

The permeability of complex porous materials can be obtained via direct flow simulation, which provides the most accurate results, but is very computationally expensive. In particular, the simulation convergence time scales poorly as…

Compressing and pruning large machine learning models has become a critical step towards their deployment in real-world applications. Standard pruning and compression techniques are typically designed without taking the structure of the…

It is known that a trained Restricted Boltzmann Machine (RBM) on the binary Monte Carlo Ising spin configurations, generates a series of iterative reconstructed spin configurations which spontaneously flow and stabilize to the critical…

Disordered Systems and Neural Networks · Physics 2022-05-11 Dimitrios Giataganas , Ching-Yu Huang , Feng-Li Lin

A coarse-grained simulation model eliminates microscopic degrees of freedom and represents a polymer by a simplified structure. A priori, two classes of coarse-grained models may be distinguished: those which are designed for a specific…

Soft Condensed Matter · Physics 2007-05-23 J. Baschnagel , J. P. Wittmer , H. Meyer

We propose a simple model for density fluctuations of aerodynamic grains, embedded in a turbulent, gravitating gas disk. The model combines a calculation for the behavior of a group of grains encountering a single turbulent eddy, with a…

Earth and Planetary Astrophysics · Physics 2015-12-23 Philip F. Hopkins

Entangled granular systems exhibit mechanical rigidity and resistance to deformation, reminiscent of cohesive materials, due to their reduced degrees of freedom and contact friction. A quantitative understanding of how classical granular…

Soft Condensed Matter · Physics 2026-02-11 Palash Sarate , Mohd. Ilyas Bhat , Tejas G. Murthy , Prerna Sharma

The spin network simulator model represents a bridge between (generalized) circuit schemes for standard quantum computation and approaches based on notions from Topological Quantum Field Theories (TQFT). More precisely, when working with…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Silvano Garnerone , Annalisa Marzuoli , Mario Rasetti

Sand production is an important issue for many hydrocarbon recovery applications in unconsolidated reservoirs. The model using the Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) can capture micro-scale features…

Computational Engineering, Finance, and Science · Computer Science 2022-11-14 Daniyar Kazidenov , Furkhat Khamitov , Yerlan Amanbek

Spin networks appear in a number of areas, for instance in lattice gauge theories and in quantum gravity. They describe the contraction of intertwiners according to the underlying network. We show that a certain generating function of…

General Relativity and Quantum Cosmology · Physics 2015-11-24 Bianca Dittrich , Jeff Hnybida

We carry out a numerical study on the dynamics of a single non-Brownian flexible fiber in two-dimensional Couette flows at finite Reynolds numbers. We employ the bead-spring model of flexible fibers to extend the fluid particle dynamics…

Soft Condensed Matter · Physics 2023-04-05 Jian Su , Kun Ma , Zhongyu Yan , Qiaolin He , Xinpeng Xu