Path integral representation of spin foam models of 4D gravity
نویسندگان
چکیده
منابع مشابه
Spin Foam Models of Riemannian Quantum Gravity
Using numerical calculations, we compare three versions of the Barrett– Crane model of 4-dimensional Riemannian quantum gravity. In the version with face and edge amplitudes as described by De Pietri, Freidel, Krasnov, and Rovelli, we show the partition function diverges very rapidly for many triangulated 4-manifolds. In the version with modified face and edge amplitudes due to Perez and Rovell...
متن کاملSpin Foam Models of Quantum Gravity
We give a short review of the spin foam models of quantum gravity , with an emphasis on the Barret-Crane model. After explaining the shortcomings of the Barret-Crane model, we briefly discuss two new approaches , one based on the 3d spin foam state sum invariants for the embedded spin networks, and the other based on representing the string scattering amplitudes as 2d spin foam state sum invari...
متن کاملSpin Foam Models for Quantum Gravity
In this article we review the present status of the spin foam formulation of nonperturbative (background independent) quantum gravity. The article is divided in two parts. In the first part we present a general introduction to the main ideas emphasizing their motivation from various perspectives. Riemannian 3-dimensional gravity is used as a simple example to illustrate conceptual issues and ma...
متن کاملSimplicity and closure constraints in spin foam models of gravity
We revise imposition of various constraints in spin foam models of 4-dimensional general relativity. We argue that the usual simplicity constraint must be supplemented by a constraint on holonomies and together they must be inserted explicitly into the discretized path integral. At the same time, the closure constraint must be relaxed so that the new constraint expresses covariance of intertwin...
متن کاملCanonical “Loop” Quantum Gravity and Spin Foam Models
The canonical “loop” formulation of quantum gravity is a mathematically well defined, background independent, non perturbative standard quantization of Einstein’s theory of General Relativity. Some among the most meaningful results of the theory are: 1) the complete calculation of the spectrum of geometric quantities like the area and the volume and the consequent physical predictions about the...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Classical and Quantum Gravity
سال: 2008
ISSN: 0264-9381,1361-6382
DOI: 10.1088/0264-9381/25/24/245010