# The variance of the CMB temperature gradient: a new signature of a multiply connected Universe

@article{Aurich2021TheVO, title={The variance of the CMB temperature gradient: a new signature of a multiply connected Universe}, author={Ralf Aurich and Thomas Buchert and Martin J. France and Frank Steiner}, journal={Classical and Quantum Gravity}, year={2021}, volume={38} }

In this work we investigate the standard deviation of the cosmic microwave background (CMB) temperature gradient field as a signature for a multiply connected nature of the Universe. CMB simulations of a spatially infinite Universe model within the paradigm of the standard cosmological model present non-zero two-point correlations at any angular scale. This is in contradiction with the extreme suppression of correlations at scales above 60° in the observed CMB maps. Universe models with…

## One Citation

Complete Relativity: Nature of observables

- 2021

A complete relativity of all observables with scale invariance in physical laws is postulated and discussed.Along with definitions of new terms which may be used in follow-up articles written in the…

## References

SHOWING 1-10 OF 120 REFERENCES

The circles-in-the-sky signature for three spherical universes

- Physics
- 2006

The mysteriously low cosmic microwave background (CMB) power on the largest scales might point to a Universe which consists of a multi-connected space. In addition to a suppression of large-scale…

Significance of the largest scale CMB fluctuations in WMAP

- Physics
- 2004

We investigate anomalies reported in the Cosmic Microwave Background maps from the Wilkinson Microwave Anisotropy Probe (WMAP) satellite on very large angular scales and discuss possible…

Unexpected topology of the temperature fluctuations in the cosmic microwave background

- Physics, MathematicsAstronomy & Astrophysics
- 2019

We study the topology generated by the temperature fluctuations of the cosmic microwave background (CMB) radiation, as quantified by the number of components and holes, formally given by the Betti…

Planck 2015 results: XVIII. Background geometry and topology of the Universe

- Physics
- 2016

Maps of cosmic microwave background (CMB) temperature and polarization from the 2015 release of Planck data provide the highest quality full-sky view of the surface of last scattering available to…

COBE and global topology: an example of the application of the identified circles principle

- Physics
- 2000

The significance to which the cosmic microwave background (CMB) observations by the satellite COBE can be used to refute a specific observationally based hypothesis for the global topology…

No large-angle correlations on the non-Galactic microwave sky

- Physics
- 2009

We investigate the angular two-point correlation function of temperature in the Wilkinson Microwave Anisotropy Probe (WMAP) maps. Updating and extending earlier results, we confirm firm the lack of…

Topology beyond the horizon: how far can it be probed?

- Physics
- 2015

The standard cosmological model does not determine the spatial topology of the universe. This article revisits the signature of a non-trivial topology on the properties of the cosmic microwave…

Planck 2013 results - XXIII. Isotropy and statistics of the CMB

- Physics
- 2014

We test the statistical isotropy and Gaussianity of the cosmic microwave background (CMB) anisotropies using observations made by the Planck satellite. Our results are based mainly on the full Planck…

The Cosmic Microwave Background for a Nearly Flat Compact Hyperbolic Universe

- Physics
- 2000

The fluctuations of the cosmic microwave background (CMB) are investigated for a hyperbolic universe with finite volume. Four-component models with radiation, matter, vacuum energy, and an extra…

Planck evidence for a closed Universe and a possible crisis for cosmology

- PhysicsNature Astronomy
- 2019

The recent Planck Legacy 2018 release has confirmed the presence of an enhanced lensing amplitude in cosmic microwave background power spectra compared with that predicted in the standard Λ cold dark…