New evidence and analysis of cosmological-scale asymmetry in galaxy spin directions
In the past several decades, multiple cosmological theories that are based on the contention that the Universe has a major axis have been proposed. Such theories can be based on the geometry of the Universe, or multiverse theories such as black hole cosmology. The contention of a cosmological-scale axis is supported by certain evidence such as the dipole axis formed by the CMB distribution. Here I study another form of the cosmological-scale axis, based on the distribution of the spin direction of spiral galaxies. Data from four different telescopes are analyzed, showing nearly identical axis profiles when the distribution of the redshifts of the galaxies is similar.
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NSF-PAR ID:
10338699
Journal Name:
Journal of astrophysics and astronomy
Volume:
43
Page Range or eLocation-ID:
24
ISSN:
0973-7758
Three-dimensional wide-field galaxy surveys are fundamental for cosmological studies. For higher redshifts (z ≳ 1.0), where galaxies are too faint, quasars still trace the large-scale structure of the Universe. Since available telescope time limits spectroscopic surveys, photometric methods are efficient for estimating redshifts for many quasars. Recently, machine-learning methods are increasingly successful for quasar photometric redshifts, however, they hinge on the distribution of the training set. Therefore, a rigorous estimation of reliability is critical. We extracted optical and infrared photometric data from the cross-matched catalogue of the WISE All-Sky and PS1 3$\pi$ DR2 sky surveys. We trained an XGBoost regressor and an artificial neural network on the relation between colour indices and spectroscopic redshift. We approximated the effective training set coverage with the K-nearest neighbours algorithm. We estimated reliable photometric redshifts of 2 562 878 quasars which overlap with the training set in feature space. We validated the derived redshifts with an independent, clustering-based redshift estimation technique. The final catalogue is publicly available.