A spin-foam vertex amplitude with the correct semiclassical limit
Abstract
Spin-foam models are hoped to provide a dynamics for loop quantum gravity. These start from the Plebanski formulation of gravity, in which gravity is obtained from a topological field theory, BF theory, through constraints, which, however, select more than one gravitational sector, as well as an unphysical degenerate sector. We show this is why terms beyond the needed Feynman-prescribed one appear in the semiclassical limit of the EPRL spin-foam amplitude. By quantum mechanically isolating a single gravitational sector, we modify this amplitude, yielding a spin-foam amplitude for loop quantum gravity with the correct semiclassical limit.
Cite
@article{arxiv.1201.2187,
title = {A spin-foam vertex amplitude with the correct semiclassical limit},
author = {Jonathan Engle},
journal= {arXiv preprint arXiv:1201.2187},
year = {2015}
}
Comments
5 pages; sign error corrected, further clarification regarding the semi-classical limit added, as well as other minor changes