248 citations · 939 across the 17 of their papers we have counts for
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Quantum gravity asymptotics from the SU(2) 15j symbol
John W. Barrett, Winston J. Fairbairn, Frank Hellmann
The asymptotics of the SU(2) 15j symbol are obtained using coherent states for the boundary data. The geometry of all non-suppressed boundary data is given. For some boundary data,…
Canonical Analysis of Algebraic String Actions
Winston J. Fairbairn, Karim Noui, Francesco Sardelli
We investigate the canonical aspects of the algebraic first order formulation of strings introduced two decades ago by Balachandran and collaborators. We slightly enlarge the Lagra…
A Summary of the asymptotic analysis for the EPRL amplitude
John W. Barrett, Richard J. Dowdall, Winston J. Fairbairn +2
We review the basic steps in building the asymptotic analysis of the Euclidean sector of new spin foam models using coherent states, for Immirzi parameter less than one. We focus o…
Lorentzian spin foam amplitudes: graphical calculus and asymptotics
John W. Barrett, Richard J. Dowdall, Winston J. Fairbairn +2
The amplitude for the 4-simplex in a spin foam model for quantum gravity is defined using a graphical calculus for the unitary representations of the Lorentz group. The asymptotics…
Asymptotic analysis of the EPRL four-simplex amplitude
John W. Barrett, R. J. Dowdall, Winston J. Fairbairn +2
The semiclassical limit of a 4-simplex amplitude for a spin foam quantum gravity model with an Immirzi parameter is studied. If the boundary state represents a non-degenerate 4-sim…