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Related papers: Obstructions to Bell CMB Experiments

200 papers

We review the present status of Cosmic Microwave Background (CMB) anisotropy observations and discuss the main related astrophysical issues, instrumental effects and data analysis techniques. We summarise the balloon-borne and ground-based…

Astrophysics · Physics 2007-05-23 M. Bersanelli , D. Maino , A. Mennella

This chapter describes how the Cosmic Gravitational Wave Background induces a specific type of CMB polarization and describes the first experiment dedicated to testing this most-promising signature of inflation. This experiment, the…

Astrophysics · Physics 2009-09-29 Brian G. Keating

The no-signalling principle is a fundamental assumption in Bell-inequality and quantum-steering experiments. Nonetheless, experimental imperfections can lead to apparent violations beyond those expected from finite-sample statistics. Here,…

The standard $\Lambda$CDM model of cosmology is largely successful in describing many observations, including precise measurements of the Cosmic Microwave Background (CMB) radiation. However, some intriguing anomalies remain currently…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-13 William Giarè

In most Bell tests, the measurement settings are specially chosen so that the maximal quantum violations of the Bell inequalities can be detected, or at least, the violations are strong enough to be observed. Such choices can usually…

Quantum Physics · Physics 2022-10-21 Weidong Tang

It is generally believed that Bell's inequality holds for the case of entangled states, including two correlated particles or special states of a single particle. Here, we derive a single-particle Bell's inequality for two correlated spin…

Quantum Physics · Physics 2007-05-23 A. Shafiee , M. Golshani

The scalar mode temperature fluctuations of the cosmic microwave background has been derived in a spatially closed universe from two different methods. First, by following the photon trajectory after the last scattering and then from the…

General Relativity and Quantum Cosmology · Physics 2017-09-27 Pedram Niazy , Amir H. Abbassi

The Bell inequalities in three and four correlations are re-derived in general forms showing that three and four data sets, respectively, identically satisfy them regardless of whether they are random, deterministic, measured, predicted, or…

Quantum Physics · Physics 2020-06-24 Louis Sica

We develop a set of controlled, analytic approximations to study the effects of bubble collisions on cosmology. We expand the initial perturbation to the inflaton field caused by the collision in a general power series, and determine its…

High Energy Physics - Theory · Physics 2015-06-04 Roberto Gobbetti , Matthew Kleban

In a recently proposed approach to testing models of inflation by Cosmic Microwave Background (CMB) radiation the reheating temperature is directly expressed in terms of the CMB observables. Its model independent bounds translate in a given…

High Energy Physics - Phenomenology · Physics 2026-04-21 Michał Marciniak , Marek Olechowski , Stefan Pokorski

Since the measurements of COBE/FIRAS in the mid-90's we know that the energy spectrum of the cosmic microwave background (CMB) is extremely close to that of a perfect blackbody at an average temperature T0~2.726K. However, a number of…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-11 Jens Chluba

We describe a new Bell test for two-particle entangled systems that engages an unbounded continuous variable. The continuous variable state is allowed to be arbitrary and inaccessible to direct measurements. A systematic method is…

Quantum Physics · Physics 2014-01-20 X. -F. Qian , C. J. Broadbent , J. H. Eberly

The recent observation of the cosmic microwave background anisotropy by the WMAP confirmed that the lower multipoles are considerably suppressed. From the standpoint of the cosmic variance, it is nothing but a statistical accident.…

High Energy Physics - Phenomenology · Physics 2009-11-10 Masahiro Kawasaki , Fuminobu Takahashi

Opto- and electromechanical systems offer an effective platform to test quantum theory and its predictions at macroscopic scales. To date, all experiments presuppose the validity of quantum mechanics, but could in principle be described by…

Quantum Physics · Physics 2016-02-24 Sebastian G. Hofer , Konrad W. Lehnert , Klemens Hammerer

We derive a Bell-type inequality for observables with arbitrary spectra. For the case of continuous variable systems we propose a possible experimental violation of this inequality, by using squeezed light and homodyne detection together…

Quantum Physics · Physics 2009-02-24 E. Shchukin W. Vogel

The cosmic microwave background (CMB) contains perturbations that are close to Gaussian and isotropic. This means that its information content, in the sense of the ability to constrain cosmological models, is closely related to the number…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-06 Douglas Scott , Dagoberto Contreras , Ali Narimani , Yin-Zhe Ma

A Bell test can rule out local realistic models, and has potential applications in communications and information tasks. For example, a Bell inequality violation can certify the presence of intrinsic randomness in measurement outcomes,…

Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

We analyse the recent claim that a violation of a Bell's inequality has been observed in the $B$--meson system [A. Go, {\em Journal of Modern Optics} {\bf 51} (2004) 991]. The results of this experiment are a convincing proof of quantum…

Quantum Physics · Physics 2009-11-10 A. Bramon , R. Escribano , G. Garbarino

The violation of Bell, CHSH and CH inequalities indicates only that the assumption of "conterfactual definiteness" and/or the probabilistic models used in proofs were incorrect. In this paper we discuss in detail an intimate relation…

Quantum Physics · Physics 2015-08-26 Marian Kupczynski