scholarly journals Nonlocal matching condition and scale-invariant spectrum in bouncing cosmology

2006 ◽  
Vol 73 (10) ◽  
Author(s):  
Chong-Sun Chu ◽  
Ko Furuta ◽  
Feng-Li Lin
Keyword(s):  
Matching Condition ◽  
Scale Invariant ◽  
Bouncing Cosmology

GENERAL MATCHING CONDITIONS IN BOUNCING COSMOLOGY AND CMB SPECTRUM

2007 ◽  
Vol 22 (25n28) ◽  
pp. 1937-1944
Author(s):  
CHONG-SUN CHU ◽  
KO FURUTA ◽  
FENG-LI LIN
Keyword(s):  
Noncommutative Geometry ◽  
Matching Condition ◽  
Effective Theory ◽  
Causality Condition ◽  
Scale Invariant ◽  
Matching Conditions ◽  
Local Causality ◽  
Bouncing Cosmology ◽  
Before And After ◽  
Specific Scenario

To clarify the issue of obtaining the scale invariant CMB spectrum in bouncing cosmology, we examine the matching condition between the metric perturbations before and after the bounce. We prove a no-go theorem: independent of the details of the matching condition, a scale invariant spectrum is impossible as long as the local causality condition is satisfied. In our framework, it is easy to show that a violation of local causality around the bounce is needed in order to give a scale invariant spectrum. We study a specific scenario of this possibility by considering a nonlocal effective theory inspired by noncommutative geometry around the bounce and show that a scale invariant spectrum is possible.

Preheating in the nonminimal derivative coupling curvaton model with nonstandard kinetic matter term

2019 ◽  
Vol 34 (15) ◽  
pp. 1950079 ◽  
Author(s):  
Xinfei Li ◽  
Jinbo Fan ◽  
Xin Liu ◽  
Gao-Ming Deng ◽  
Yong-Chang Huang
Keyword(s):  
Large Scale ◽  
Scale Invariant ◽  
Curvature Perturbation ◽  
Derivative Coupling ◽  
Bouncing Cosmology

The curvaton scenario received much attention recently. It provides an alternative way to generate scale-invariant perturbations for the observed universe, besides the standard inflation paradigm. This paper studies the preheating in the nonminimal derivative coupling curvaton model with a nonstandard kinetic matter term, as a consequence of the large scale power spectrums of curvature perturbation. It is found that the nonstandard kinetic matter term is able to modify the behavior of the preheating, compared to the nonminimal derivative coupling curvaton model with standard kinetic matter term. Our result may provide an insight to the preheating process for bouncing cosmology or brane-inspired cosmology.

scholarly journals A smooth bouncing cosmology with scale invariant spectrum

2007 ◽  
Vol 2007 (11) ◽  
pp. 010-010 ◽  
Author(s):  
Paolo Creminelli ◽  
Leonardo Senatore
Keyword(s):  
Scale Invariant ◽  
Bouncing Cosmology

Scale-Invariant Theory of Optical Properties of Fractal Clusters

1990 ◽  
Author(s):  
Vadim A. Markel ◽  
Leonid S. Muratov ◽  
Mark I. Stockman ◽  
Thomas F. George
Keyword(s):  
Optical Properties ◽  
Invariant Theory ◽  
Scale Invariant ◽  
Fractal Clusters

Best Matching: Technical Details

2018 ◽  
Author(s):  
Flavio Mercati
Keyword(s):  
Point Particle ◽  
Euclidean Group ◽  
Scale Invariant ◽  
Similarity Group ◽  
N Body Problem ◽  
Technical Details ◽  
Matching Procedure ◽  
Principal Fibre ◽  
Principal Fibre Bundle ◽  
Gauge Connection

The best matching procedure described in Chapter 4 is equivalent to the introduction of a principal fibre bundle in configuration space. Essentially one introduces a one-dimensional gauge connection on the time axis, which is a representation of the Euclidean group of rotations and translations (or, possibly, the similarity group which includes dilatations). To accommodate temporal relationalism, the variational principle needs to be invariant under reparametrizations. The simplest way to realize this in point–particle mechanics is to use Jacobi’s reformulation of Mapertuis’ principle. The chapter concludes with the relational reformulation of the Newtonian N-body problem (and its scale-invariant variant).

Sign in / Sign up

Export Citation Format

Share Document