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The Spin-Foam Approach to Quantum Gravity [PDF]

Living Reviews in Relativity, 2013
This article reviews the present status of the spin-foam approach to the quantization of gravity. Special attention is payed to the pedagogical presentation of the recently-introduced new models for four-dimensional quantum gravity.
Alejandro Perez
doaj   +10 more sources

Spin Foams and Canonical Quantization [PDF]

Symmetry, Integrability and Geometry: Methods and Applications, 2012
This review is devoted to the analysis of the mutual consistency of the spin foam and canonical loop quantizations in three and four spacetime dimensions.
Sergei Alexandrov, Marc Geiller, Karim Noui   +2 more
doaj   +8 more sources

Positivity of Spin Foam Amplitudes [PDF]

Classical and Quantum Gravity, 2001
The amplitude for a spin foam in the Barrett-Crane model of Riemannian quantum gravity is given as a product over its vertices, edges and faces, with one factor of the Riemannian 10j symbols appearing for each vertex, and simpler factors for the edges ...
Ambjørn J, Arnsdorf M, Ashtekar A, Baez J C, Baez J C, Baez J C, Baez J C, Barrett J W, Barrett J W, Carter J S, Christensen J D, Crane L, Freidel L, J Daniel Christensen, John C Baez, Kauffman L, Massey W, Oriti D, Press W H, Rourke C, Yetter D N   +20 more
core   +8 more sources

4-dimensional Spin-foam Model with Quantum Lorentz Group [PDF]

, 2011
We study the quantum group deformation of the Lorentzian EPRL spin-foam model. The construction uses the harmonic analysis on the quantum Lorentz group.
Han, Muxin
core   +4 more sources

Group field theories for all loop quantum gravity

New Journal of Physics, 2015
Group field theories represent a second quantized reformulation of the loop quantum gravity state space and a completion of the spin foam formalism. States of the canonical theory, in the traditional continuum setting, have support on graphs of arbitrary
Daniele Oriti, James P Ryan, Johannes Thürigen   +2 more
doaj   +2 more sources

Four-Dimensional Spin Foam Perturbation Theory [PDF]

Symmetry, Integrability and Geometry: Methods and Applications, 2011
We define a four-dimensional spin-foam perturbation theory for the BF-theory with a B∧B potential term defined for a compact semi-simple Lie group G on a compact orientable 4-manifold M.
João Faria Martins, Aleksandar Mikovic
doaj   +5 more sources

Optimizing Osseodensification Drilling for Dental Implant Placement: An In Vitro Study [PDF]

Clinical and Experimental Dental Research
Objectives This study aims to optimize the parameters of osseodensification drilling (OD) to improve the primary stability of dental implants in low‐density bone.
Xingru Tao, Jie Yang, Tai Ma, Ming Chen, Qinglong An, Dedong Yu   +5 more
doaj   +2 more sources

Enhancing Tennis Practice: Sensor Fusion and Pose Estimation with a Smart Tennis Ball [PDF]

Sensors
This article demonstrates the integration of sensor fusion for pose estimation and data collection in tennis balls, aiming to create a smaller, less intrusive form factor for use in progressive learning during tennis practice.
Yu Kit Foo, Xi Li, Rami Ghannam
doaj   +2 more sources

How-to Compute EPRL Spin Foam Amplitudes

Universe, 2022
Spin foam theory is a concrete framework for quantum gravity where numerical calculations of transition amplitudes are possible. Recently, the field became very active, but the entry barrier is steep, mainly because of its unusual language and notions ...
Pietro Donà, Pietropaolo Frisoni
doaj   +1 more source

Elucidating the Chirality-Induced Spin Selectivity Effect of Co-Doped NiO Deposited on Ni Foam for Highly Stable Zn-Air Batteries. [PDF]

ACS Appl Mater Interfaces
Park YS, Lee J, Lee H, Park JB, Yun J, Lee CU, Moon S, Lee S, Kim S, Kim JH, Kim D, Han J, Kim DW, Moon J.   +13 more
europepmc   +2 more sources