Talk detail

Participant	Gupt, Brajesh
Institution	Pennsylvania State University - 104 Davey Lab - University Park - Pennsylvania - USA

Session	QG3	Accepted	Yes	Order	9	Time	17:15	15'
Talk	Oral abstract	Title	Robustness of phenomenological consequences of quantum geometries in loop quantum cosmology
Coauthors
Abstract	Over the past decade loop quantum cosmology (LQC) has matured appreciably while making progress of both fronts: observational signatures in the cosmic microwave background (CMB) and resolution of cosmological singularity. Due to the modified dynamics in the pre-inflationary era the initial conditions for both the background and cosmological perturbations are different from those in the standard inflationary scenario. These modifications can lead to imprints on the CMB. In this talk we study the robustness of these results from various fronts by considering general states of large dispersions for the background evolution as well as more general vacuum states for cosmological perturbations. We find that a generalized notion of the so called effective description emerges. Moreover, general states do not add any new parameter and the previous results are robust under these generalizations. We will also discuss some of the recent developments towards new observational consequences of loop quantum geometry on the CMB.
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Session	CM2-3	Accepted	Yes	Order	99	Time
Talk	Poster abstract	Title	Power suppression at low multipoles in loop quantum cosmology
Coauthors	Ashtekar, Abhay
Abstract	We investigate observational signatures of the Planck scale physics of loop quantum cosmology (LQC) on the cosmic microwave background (CMB) temperature anisotropy spectrum. Due to the modified dynamics in the pre-inflationary era the initial conditions for both the background and cosmological perturbations in LQC are different from those in the standard inflationary scenario. We find that such modifications can lead to observational signatures and provide a new window to explore the CMB anomalies. In particular, we show that LQC admits initial conditions for which the resulting power spectrum at the end of inflation has less power at large wavelengths. This leads to suppression of power in ($\mathcal C_\ell^{TT}$) at low multipoles (l < 30). We compare our results with the recent observational data and compute the consequences of the power suppression on TE and EE polarization spectrum at the corresponding scales, which are expected to be measured by future CMB observations.
Pdf file