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Related papers: Hemispherical Power Asymmetry from Scale-Dependent…

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Recent measurements of the temperature field of Cosmic Microwave Background (CMB) provide tantalising evidence for violation of Statistical Isotropy (SI) that constitutes a fundamental tenet of contemporary cosmology. CMB space based…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Suvodip Mukherjee , Tarun Souradeep

One of the foundations of the Standard Model of Cosmology is statistical isotropy, which can be tested, among other probes, through the study of the Cosmic Microwave Background (CMB). However, a hemispherical power asymmetry on large scales…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-15 C. Gimeno-Amo , R. B. Barreiro , E. Martínez-González , A. Marcos-Caballero

A persistent signal of power asymmetry on opposite hemispheres of CMB sky was seen in full-sky temperature measurements made so far. This asymmetry was seen in microwave sky from WMAP as well as PLANCK satellites, and calls for attention…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-03 Pavan K. Aluri , Arman Shafieloo

We study temperature and polarization anisotropies of the cosmic microwave background (CMB) radiation sourced from primordial cross-bispectra between metric perturbations and vector fields, which are generated from the inflation model where…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-18 Maresuke Shiraishi , Shohei Saga , Shuichiro Yokoyama

We review aspects of Cosmic Microwave Background (CMB) spectral distortions which do not appear to have been fully explored in the literature. In particular, implications of recent evidences of heating of the intergalactic medium (IGM) by…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 G. De Zotti , M. Negrello , G. Castex , A. Lapi , M. Bonato

We perform a joint analysis of the power spectrum and the bispectrum of the CMB temperature and polarization anisotropies to improve the constraints on isocurvature modes. We construct joint likelihoods, both for the existing Planck data,…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-19 Thomas Montandon , Guillaume Patanchon , Bartjan van Tent

We consider cosmological scenarios in which density perturbations are generated by the quantum fluctuations of the inflaton field at early times; the late time dynamics involves a modulus which first dominates the energy density of the…

High Energy Physics - Phenomenology · Physics 2015-03-09 Koushik Dutta , Anshuman Maharana

Non-linear effects in the early Universe generate non-zero bispectra of the cosmic microwave background (CMB) temperature and polarization, even in the absence of primordial non-Gaussianity. In this paper, we compute the contributions from…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-09 Pedro Carrilho , Karim A. Malik

Observations indicate that large-scale anomalies exist in the fluctuations of the cosmic microwave background. In these anomalies, the hemispherical power amplitude asymmetry has a correlation length comparable to that of the observable…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-19 Qiaoli Yang , Yunqi Liu , Haoran Di

Planck's residuals of the CMB temperature power spectrum present a curious oscillatory shape that resembles an extra smoothing effect of lensing and is the source of the lensing anomaly. The smoothing effect of lensing to the CMB…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-22 Guillem Domènech , Xingang Chen , Marc Kamionkowski , Abraham Loeb

We investigate the primordial scalar perturbations in the thermal dissipative inflation where the radiation component (thermal bath) persists and the density fluctuations are thermally originated. The perturbation generated in this model is…

Astrophysics · Physics 2009-11-10 Wolung Lee , Li-Zhi Fang

We investigate the potential of the galaxy power spectrum to constrain compensated isocurvature perturbations (CIPs), primordial fluctuations in the baryon density that are compensated by fluctuations in CDM density to ensure an unperturbed…

Cosmology and Nongalactic Astrophysics · Physics 2020-09-22 Alexandre Barreira , Giovanni Cabass , Kaloian D. Lozanov , Fabian Schmidt

Anomalies in the large-scale CMB temperature sky measured by WMAP have been suggested as possible evidence for a violation of statistical isotropy on large scales. In any physical model for broken isotropy, there are testable consequences…

Astrophysics · Physics 2008-12-18 Cora Dvorkin , Hiranya V. Peiris , Wayne Hu

We study the cosmic microwave background (CMB) anisotropy in the scenario where the baryon asymmetry of the universe is generated from a condensation of a scalar field. In such a scenario, the scalar condensation may acquire fluctuation…

High Energy Physics - Phenomenology · Physics 2009-09-29 Takeo Moroi , Hitoshi Murayama

It is proposed that if quantum states of space-time are coherent on null surfaces, holographic Planck-scale fluctuations of inflationary horizons dominate the formation of primordial scalar curvature perturbations. It is shown that the…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Craig Hogan

We reconsider the observed CMB dipolar asymmetry in the context of open inflation, where a supercurvature mode might survive the bubble nucleation. If such a supercurvature mode modulates the amplitude of the curvature power spectrum, it…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Christian Byrnes , Guillem Domènech , Misao Sasaki , Tomo Takahashi

As additional perturbative degrees of freedom, it is known that magnetic fields of inflationary origin can source curvature perturbations on super-Hubble scales. By requiring the magnetic generated curvature to remain smaller than its…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Christophe Ringeval , Teruaki Suyama , Jun'ichi Yokoyama

The recent Planck results and future releases on the horizon present a key opportunity to address a fundamental question in inflationary cosmology of whether primordial density perturbations have a quantum or thermal origin, i.e. whether…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-20 Sam Bartrum , Arjun Berera , Joao G. Rosa

We present the first Bayesian constraints on the single field inflationary reheating era obtained from Cosmic Microwave Background (CMB) data. After demonstrating that this epoch can be fully characterized by the so-called reheating…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jerome Martin , Christophe Ringeval

A common explanation for the CMB power asymmetry is to introduce a dipolar modulation at the stage of inflation, where the primordial power spectrum is spatially varying. If the universe in the stage of inflation is Finslerian, and if the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-28 Xin Li , Hai-Nan Lin
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