https://doi.org/10.1140/epjc/s10052-022-10866-0
Regular Article - Theoretical Physics
Galaxy distributions as fractal systems
1
Valongo Observatory, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
2
Department of Astronomy, Observatório Nacional, Rio de Janeiro, Brazil
3
Instituto de Astrofísica de La Plata, CONICET-UNLP, La Plata, Argentina
4
Physics Institute, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
Received:
6
May
2022
Accepted:
28
September
2022
Published online:
10
October
2022
This paper discusses if large scale galaxy distribution samples containing almost one million objects can be characterized as fractal systems. The analysis performed by Teles et al. (Phys Lett B 813:136034, 2021) on the UltraVISTA DR1 survey is extended here to the SPLASH and COSMOS2015 catalogs, hence adding 750k new galaxies with measured redshifts to the studied samples. The standard 
CDM cosmology having 
km/s/Mpc and number density tools required for describing these galaxy distributions as single fractal systems with dimension D are adopted. We use the luminosity distance 
, redshift distance 
and galaxy area distance (transverse comoving distance) 
as relativistic distance definitions to derive galaxy number densities in the redshift interval 
at volume limited subsamples defined by absolute magnitudes in the K-band. Similar to the findings of Teles et al. (2021), the results show two consecutive redshift scales where galaxy distribution data behave as single fractal structures. For 
we found 
for the SPLASH galaxies, and 
for the COSMOS2015. For 
we respectively found 
and 
. These results were verified to be robust under the assumed Hubble constant uncertainty. Calculations considering blue and red galaxies subsamples in both surveys showed that the fractal dimensions of blue galaxies as basically unchanged, but the ones for the red galaxies changed mostly to smaller values, meaning that D may be seen as a more intrinsic property of the distribution of objects in the Universe, therefore allowing for the fractal dimension to be used as a tool to study different populations of galaxies. All results confirm the decades old theoretical prediction of a decrease in the fractal dimension for 
.
© The Author(s) 2022
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
Funded by SCOAP3. SCOAP3 supports the goals of the International Year of Basic Sciences for Sustainable Development.
