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Continuous Spontaneous Localization (CSL) model of Quantum Mechanics modifies Schr\"{o}dinger equation by adding non-linear stochastic terms due to which the total energy of a system increases with a constant rate which is proportional to…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-04 Suratna Das , Kinjalk Lochan , Angelo Bassi

Measurements of CMB anisotropy and, more recently, polarization have played a very important role in cosmology. Besides precise determination of various parameters of the `standard' cosmological model, observations have also established…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-02 Tarun Souradeep

Observational Cosmology has indeed made very rapid progress in the past decade. The ability to quantify the universe has largely improved due to observational constraints coming from structure formation Measurements of CMB anisotropy and,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tarun Souradeep

Extensions to the $\Lambda\textrm{CDM}$ model prior to recombination can modify the growth of perturbations around radiation-matter equality, leaving a distinct signature in the matter power spectrum. Upcoming large-scale structure surveys…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-09 Raphaël Kou , Antony Lewis

Emergent cosmological models, together with the Big Bang and bouncing scenarios, are among the possible descriptions of the early Universe. This work aims at clarifying some general features of the primordial tensor power spectrum in this…

General Relativity and Quantum Cosmology · Physics 2018-12-14 Killian Martineau , Aurélien Barrau

A B-mode polarization signal in the cosmic microwave background (CMB) is widely regarded as smoking gun evidence for gravitational waves produced during inflation. Here, we demonstrate that tensor perturbations sourced during…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-22 Kylar Greene , Aurora Ireland , Gordan Krnjaic , Yuhsin Tsai

The Continuous Spontaneous Localization (CSL) model strives to describe the quantum-to-classical transition from the viewpoint of collapse models. However, its original formulation suffers from a fundamental inconsistency in that it is…

Quantum Physics · Physics 2018-10-17 J. Nobakht , M. Carlesso , S. Donadi , M. Paternostro , A. Bassi

Different inflationary models predict oscillatory features in the primordial power spectrum. These can leave an imprint on both the cosmic microwave background (CMB) and the large-scale structure (LSS) of our Universe, that can be searched…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-15 Chenxiao Zeng , Ely D. Kovetz , Xuelei Chen , Yan Gong , Julian B. Muñoz , Marc Kamionkowski

In this work we explore the possibility of variations in the primordial scalar power spectrum around the power-law shape, as predicted by single-field slow-roll inflationary scenarios. We search for the trace of these fluctuations in a…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 Marzieh Farhang , Muhammad Sadegh Esmaeilian

It is well known that CMB temperature anisotropies and polarization can be used to probe the metric perturbations in the early universe. Presently, there exist neither any observational detection of tensor modes of primordial metric…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-23 Gaurav Goswami , Jayanti Prasad

In a recent paper [17], we studied the evolution of the background geometry and scalar perturbations in an inflationary, spatially closed Friedmann-Lema\^itre-Robertson-Walker (FLRW) model having constant positive spatial curvature and…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-24 Béatrice Bonga , Brajesh Gupt , Nelson Yokomizo

We study the degree to which the cosmic microwave background (CMB) can be used to constrain primordial non-Gaussianity involving one tensor and two scalar fluctuations, focusing on the correlation of one polarization $B$ mode with two…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 P. Daniel Meerburg , Joel Meyers , Alex van Engelen , Yacine Ali-Haïmoud

Collapse models explain the absence of quantum superpositions at the macroscopic scale, while giving practically the same predictions as quantum mechanics for microscopic systems. The Continuous Spontaneous Localization (CSL) model is the…

Quantum Physics · Physics 2015-08-10 Andrea Smirne , Angelo Bassi

We study the dynamics and predictions of a new emergent-universe model recently derived within Quantum Reduced Loop Gravity and based on the so-called statistical regularization scheme. These effective geometries show a dynamical transition…

General Relativity and Quantum Cosmology · Physics 2019-04-24 Javier Olmedo , Emanuele Alesci

We revisit an inflationary scenario in which primordial inhomogeneities arise from a quantum collapse, a stochastic mechanism described in the context of quantum collapse theories in its continuous version and within semiclassical gravity.…

General Relativity and Quantum Cosmology · Physics 2026-03-04 María Pía Piccirilli , Gabriel León , Rosa-Laura Lechuga-Solis , Daniel Sudarsky

We consider the effects of entanglement in the initial quantum state of scalar and tensor fluctuations during inflation. We allow the gauge-invariant scalar and tensor fluctuations to be entangled in the initial state and compute…

High Energy Physics - Theory · Physics 2017-01-13 Nadia Bolis , Andreas Albrecht , R. Holman

Detailed study of the scalar and tensor perturbation spectra can provide much information about the primordial fluctuation-generator, be it inflation or something else. The tensor perturbation spectrum may be observable through its…

Astrophysics · Physics 2007-05-23 L. Knox

Non-trivial spatial topology of the Universe can imprint potentially observable signatures on the cosmic microwave background (CMB). In this study, we investigate how deviations from the standard nearly-scale-free primordial power spectrum…

Many models of the early universe predict that there should be primordial tensor perturbations. These leave an imprint into the temperature and polarisation anisotropies of the cosmic microwave background (CMB). The differential equation…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-04 Darsh Kodwani , P. Daniel Meerburg , Ue-Li Pen , Xin Wang

We present Capse.jl, a novel neural network-based emulator designed for rapid and accurate prediction of Cosmic Microwave Background (CMB) temperature, polarization, and lensing angular power spectra. The emulator computes predictions in…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-02 Marco Bonici , Federico Bianchini , Jaime Ruiz-Zapatero