# Alleviating the tension in CMB using Planck-scale Physics

@article{Ashtekar2020AlleviatingTT, title={Alleviating the tension in CMB using Planck-scale Physics}, author={Abhay Ashtekar and Brajesh Gupt and Donghui Jeong and Vijayakumar Sreenath}, journal={arXiv: Cosmology and Nongalactic Astrophysics}, year={2020} }

Certain anomalies in the CMB bring out a tension between the six-parameter flat $\Lambda$CDM model and the CMB data. We revisit the PLANCK analysis with loop quantum cosmology (LQC) predictions and show that LQC alleviates both the large-scale power anomaly and the tension in the lensing amplitude. These differences arise because, in LQC, the primordial power spectrum is scale dependent for small $k$, with a specific power suppression. We conclude with a prediction of larger optical depth and…

## 14 Citations

Large scale anomalies in the CMB and non-Gaussianity in bouncing cosmologies

- PhysicsClassical and Quantum Gravity
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We propose that several of the anomalies that have been observed at large angular scales in the CMB have a common origin in a cosmic bounce that took place before the inflationary era. The bounce…

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We study the compatibility of the quantum homogeneitiy and isotropy hypothesis (QHIH), proposed by Ashtekar and Gupt to restrict the choice of vacuum state for the cosmological perturbations in Loop…

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We study the imprint that certain quantization ambiguities may leave in effective regimes of the hybrid loop quantum description of cosmological perturbations. More specifically, in the case of…

Quantization ambiguities and the robustness of effective descriptions of primordial perturbations in hybrid Loop Quantum Cosmology

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- 2021

We study the imprint that certain quantization ambiguities may leave in effective regimes of the hybrid loop quantum description of cosmological perturbations. More specifically, in the case of…

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- MathematicsClassical and Quantum Gravity
- 2021

The authors previously introduced a diffeomorphism-invariant definition of a homogeneous and isotropic sector of loop quantum gravity (LQG), along with a program to embed loop quantum cosmology (LQC)…

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