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arXiv · 2602.05309

Fractal dimension of the cosmic web with different galaxy types

Ana Elisa Lima·Julianne C. Soares·Ana Carolina S. Tavares·Mariana V. Taveira·Sharon Teles·Amanda R. Lopes·Marcelo B. Ribeiro
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Abstract

The fractal dimension $D$ is used to map the large-scale galaxy distribution in the Universe by color types: blue, green and red. Using a $NUVrK$-complete COSMOS2020 subsample of 618,952 galaxies observed up to $z=4$, number densities were derived and plotted against two cosmological distance measures, the luminosity and comoving (galaxy area) distances, in order to estimate $D$ for each galaxy color type in two redshift intervals: $z\gtrless1$. We found a general gradient $D_{\mathrm{blue}}> D_{\mathrm{red}}>D_{\mathrm{green}}$ with $D=1.40-2.03$ for $z<1$. For $1 D_{\mathrm{green}}>D_{\mathrm{red}}$, and the fractal dimension values are lower, $D=0.03-0.44$. These results suggest that the fractal dimension is a sensitive diagnostic for how galaxy populations trace the evolving cosmic web, and confirm the fractal dimension as a useful tool for observational mapping of large-scale structure by galaxy color.

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Ana Elisa Lima, Julianne C. Soares, Ana Carolina S. Tavares, Mariana V. Taveira, Sharon Teles, Amanda R. Lopes, Marcelo B. Ribeiro. 2026-02-05. Fractal dimension of the cosmic web with different galaxy types. https://arxiv.org/abs/2602.05309

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