290 research outputs found
How universe evolves with cosmological and gravitational constants
With a basic varying space-time cutoff , we study a regularized
and quantized Einstein-Cartan gravitational field theory and its domains of
ultraviolet-unstable fixed point and ultraviolet-stable
fixed point of the gravitational gauge coupling
. Because the fundamental operators of quantum
gravitational field theory are dimension-2 area operators, the cosmological
constant is inversely proportional to the squared correlation length
. The correlation length characterizes an
infrared size of a causally correlate patch of the universe. The cosmological
constant and the gravitational constant are related by a
generalized Bianchi identity. As the basic space-time cutoff
decreases and approaches to the Planck length , the universe
undergoes inflation in the domain of the ultraviolet-unstable fixed point
, then evolves to the low-redshift universe in the domain of
ultraviolet-stable fixed point . We give the quantitative
description of the low-redshift universe in the scaling-invariant domain of the
ultraviolet-stable fixed point , and its deviation from the
CDM can be examined by low-redshift cosmological
observations, such as supernova Type Ia.Comment: typo corrections, the final version to appear in Nucl. Phys. B
(2015). 24 pages and 6 figure
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