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Related papers: Graphical Evolution of Spin Network States

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This paper introduces a probabilistic approach for tracking the dynamics of unweighted and directed graphs using state-space models (SSMs). Unlike conventional topology inference methods that assume static graphs and generate point-wise…

Signal Processing · Electrical Eng. & Systems 2024-09-13 Victor M. Tenorio , Elvin Isufi , Geert Leus , Antonio G. Marques

In loop quantum gravity, states of quantum geometry are represented by classes of knotted graphs, equivalent under diffeomorphisms. Thus, it is worthwhile to enumerate and distinguish these classes. This paper looks at the case of 4-regular…

General Relativity and Quantum Cosmology · Physics 2023-02-09 Daniel Cartin

We illustrate the relationship between spin networks and their dual representation by labelled triangulations of space in 2+1 and 3+1 dimensions. We apply this to the recent proposal for causal evolution of spin networks. The result is…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Fotini Markopoulou

Spinfoam models provide a covariant formulation of the dynamics of loop quantum gravity. They are non-perturbatively defined in the group field theory (GFT) framework: the GFT partition function defines the sum of spinfoam transition…

General Relativity and Quantum Cosmology · Physics 2015-05-28 Etera R. Livine , Daniele Oriti , James P. Ryan

Results that illuminate the physical interpretation of states of nonperturbative quantum gravity are obtained using the recently introduced loop variables. It is shown that: i) While local operators such as the metric at a point may not be…

High Energy Physics - Theory · Physics 2011-04-20 Abhay Ashtekar , Carlo Rovelli , Lee Smolin

We present a Hamiltonian that can be used for amplifying the signal from a quantum state, enabling the measurement of a macroscopic observable to determine the state of a single spin. We prove a general mapping between this Hamiltonian and…

Quantum Physics · Physics 2007-05-23 A. Kay

We derive a spacetime formulation of quantum general relativity from (hamiltonian) loop quantum gravity. In particular, we study the quantum propagator that evolves the 3-geometry in proper time. We show that the perturbation expansion of…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Michael P Reisenberger , Carlo Rovelli

Motivated by the idea that, in the background-independent framework of a Quantum Theory of Gravity, entanglement is expected to play a key role in the reconstruction of spacetime geometry, we investigate the possibility of using the…

General Relativity and Quantum Cosmology · Physics 2017-03-21 Fabio M. Mele

We study the time evolution of continuous-time quantum walks on randomly changing graphs. At certain moments edges of the graph appear or disappear with a given probability. We focus on the case when the time interval between subsequent…

Quantum Physics · Physics 2014-09-04 Zoltán Darázs , Tamás Kiss

Several approaches to the dynamics of loop quantum gravity involve discretizing the equations of motion. The resulting discrete theories are known to be problematic since the first class algebra of constraints of the continuum theory…

General Relativity and Quantum Cosmology · Physics 2009-01-16 Rodolfo Gambini , Jorge Pullin

The spinfoam framework is a proposal for a regularized path integral for quantum gravity. Spinfoams define quantum space-time structures describing the evolution in time of the spin network states for quantum geometry derived from Loop…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Maité Dupuis

The spin network simulator model represents a bridge between (generalised) circuit schemes for standard quantum computation and approaches based on notions from Topological Quantum Field Theories (TQFTs). The key tool is provided by the…

Quantum Physics · Physics 2009-01-06 Annalisa Marzuoli , Mario Rasetti

The time evolution of physical systems is described by differential equations, which depend on abstract quantities like energy and force. Traditionally, these quantities are derived as functionals based on observables such as positions and…

Machine Learning · Computer Science 2023-07-12 Suresh Bishnoi , Ravinder Bhattoo , Jayadeva , Sayan Ranu , N M Anoop Krishnan

We provide a mathematically and conceptually robust notion of quantum superpositions of graphs. We argue that, crucially, quantum superpositions of graphs require node names for their correct alignment, which we demonstrate through a…

General Relativity and Quantum Cosmology · Physics 2023-03-09 Pablo Arrighi , Marios Christodoulou , Amélia Durbec

I introduce a new type of continuous-time quantum walk on graphs called the quantum snake walk, the basis states of which are fixed-length paths (snakes) in the underlying graph. First I analyze the quantum snake walk on the line, and I…

Quantum Physics · Physics 2013-05-29 Ansis Rosmanis

In this thesis we consider the problem of dynamics in canonical loop quantum gravity, primarily in the context of deparametrized models, in which a scalar field is taken as a physical time variable for the dynamics of the gravitational…

General Relativity and Quantum Cosmology · Physics 2021-01-01 Ilkka Mäkinen

As a toy model for the implementation of the diffeomorphism constraint, the interpretation of the resulting states, and the treatment of ordering ambiguities in loop quantum gravity, we consider the Hilbert space of spatially diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Hanno Sahlmann

I describe a possible perspective on the current state of loop quantum gravity, at the light of the developments of the last years. I point out that a theory is now available, having a well-defined background-independent kinematics and a…

General Relativity and Quantum Cosmology · Physics 2011-05-25 Carlo Rovelli

Within the framework of an idealized theoretical model, we study the effect of external static homogeneous exchange and magnetic field on the spin part of the singlet wave function of two electrons. We begin by revising the traditional…

Quantum Physics · Physics 2021-11-09 S. V. Kuplevakhsky , S. V. Bengus

We introduce a change of perspective on tensor network states that is defined by the computational graph of the contraction of an amplitude. The resulting class of states, which we refer to as tensor network functions, inherit the…

Quantum Physics · Physics 2025-01-06 Wen-Yuan Liu , Si-Jing Du , Ruojing Peng , Johnnie Gray , Garnet Kin-Lic Chan