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Related papers: U(N) tools for Loop Quantum Gravity: The Return of…

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In this work, we investigate the 4d path integral for Euclidean quantum gravity on a hypercubic lattice, as given by the Spin Foam model by Engle, Pereira, Rovelli, Livine, Freidel and Krasnov (EPRL-FK). To tackle the problem, we restrict…

General Relativity and Quantum Cosmology · Physics 2016-05-25 Benjamin Bahr , Sebastian Steinhaus

In this work, we extend the so-called typicality approach, originally formulated in statistical mechanics contexts, to $SU(2)$-invariant spin-network states. Our results do not depend on the physical interpretation of the spin network;…

General Relativity and Quantum Cosmology · Physics 2016-11-02 Fabio Anzà , Goffredo Chirco

We introduce the set of framed convex polyhedra with N faces as the symplectic quotient C^2N//SU(2). A framed polyhedron is then parametrized by N spinors living in C^2 satisfying suitable closure constraints and defines a usual convex…

Mathematical Physics · Physics 2015-06-16 Etera R. Livine

We consider the quantization of gravity as an SL(2,C) gauge theory in terms of Ashtekar's selfdual variables and reality conditions for the spatial metric (RCI) and its evolution (RCII). We start from a holomorphic phase space formulation.…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Hanno Sahlmann , Robert Seeger

In this work, we study the classical and quantum properties of the unique commutative Lorentz-covariant connection for loop quantum gravity. This connection has been found after solving the second-class constraints inherited from the…

General Relativity and Quantum Cosmology · Physics 2011-08-12 Marc Geiller , Marc Lachieze-Rey , Karim Noui

Spin network states are a powerful tool for constructing the $SU(2)$ gauge theories on a graph. In loop quantum gravity (LQG), they have yielded many promising predictions, although progress has been limited by the computational challenge…

General Relativity and Quantum Cosmology · Physics 2023-04-10 Grzegorz Czelusta , Jakub Mielczarek

The simplicial framework of Engle-Pereira-Rovelli-Livine spin-foam models is generalized to match the diffeomorphism invariant framework of loop quantum gravity. The simplicial spin-foams are generalized to arbitrary linear 2-cell…

General Relativity and Quantum Cosmology · Physics 2015-03-13 Wojciech Kamiński , Marcin Kisielowski , Jerzy Lewandowski

Graphical techniques provide a very useful practical device for calculations involving the so-called spin network states, which encode the quantum degrees of freedom of spatial geometry in loop quantum gravity. Graphical calculus of SU(2),…

General Relativity and Quantum Cosmology · Physics 2023-04-04 Emanuele Alesci , Ilkka Mäkinen , Jinsong Yang

We embark on the vast program of integrating the dynamics of Loop Quantum Gravity (LQG). Adopting the strategy of decomposing spin network states into small blocks of (quantum) geometry which can later be glued back together, we focus on…

General Relativity and Quantum Cosmology · Physics 2026-01-30 Mehdi Assanioussi , Etera R. Livine

In this work we investigate the canonical quantization of 2+1 gravity with cosmological constant $\Lambda>0$ in the canonical framework of loop quantum gravity. The unconstrained phase space of gravity in 2+1 dimensions is coordinatized by…

General Relativity and Quantum Cosmology · Physics 2012-08-15 Karim Noui , Alejandro Perez , Daniele Pranzetti

In the context of the quest for a holographic formulation of quantum gravity, we investigate the basic boundary theory structure for loop quantum gravity. In 3+1 space-time dimensions, the boundary theory lives on the 2+1-dimensional…

High Energy Physics - Theory · Physics 2021-01-20 Etera R. Livine

We present a separable version of Loop Quantum Gravity (LQG) based on an inductive system of cubic lattices. We construct semi-classical states for which the LQG operators -- the flux, the area and the volume operators -- have the right…

General Relativity and Quantum Cosmology · Physics 2009-11-24 Johannes Aastrup , Jesper M. Grimstrup

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

We investigate the Hilbert space in the Lorentz covariant approach to loop quantum gravity. We restrict ourselves to the space where all area operators are simultaneously diagonalizable, assuming that it exists. In this sector quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergei Alexandrov

The relation between Loop Quantum Gravity (LQG) and tensor network is explored from the perspectives of bulk-boundary duality and holographic entanglement entropy. We find that the LQG spin-network states in a space $\Sigma$ with boundary…

High Energy Physics - Theory · Physics 2017-01-24 Muxin Han , Ling-Yan Hung

We present a new method for constructing operators in loop quantum gravity. The construction is an application of the general idea of "coherent state quantization", which allows one to associate a unique quantum operator to every function…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Emanuele Alesci , Andrea Dapor , Jerzy Lewandowski , Ilkka Makinen , Jan Sikorski

The study of toy models in loop quantum gravity (LQG), defined as truncations of the full theory, is relevant to both the development of the LQG phenomenology, in cosmology and astrophysics, and the progress towards the resolution of the…

General Relativity and Quantum Cosmology · Physics 2022-07-13 Eneko Aranguren , Iñaki Garay , Etera R. Livine

This paper constructs coherent states for spin networks with planar symmetry. After gauge-fixing, the full SU(2) symmetry is broken to U(1), but one cannot simply use the U(1) limit of SU(2) coherent states, because the planar states…

General Relativity and Quantum Cosmology · Physics 2013-04-30 Donald E. Neville

Loop Quantum Gravity provides a natural truncation of the infinite degrees of freedom of gravity, obtained by studying the theory on a given finite graph. We review this procedure and we present the construction of the canonical theory on a…

General Relativity and Quantum Cosmology · Physics 2012-03-27 Enrique F. Borja , Iñaki Garay , Francesca Vidotto