We acknowledge financial support from the research project PRE2021-098736 funded by MCIN/AEI/10.13039/501100011033 and FSE+. We acknowledge financial support by the research projects PID2020-113689GB-I00, PID2023-149578NB-I00, and PID2020-114414GB-I00, financed by MCIN/AEI/10.13039/501100011033, the project A-FQM-510-UGR20 financed from FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades/Proyecto and by the grants P20_00334 and FQM108, financed by the Junta de Andalucía (Spain). We also acknowledge financial support from AST22.4.4, funded by Consejería de Universidad, Investigación e Innovación and Gobierno de España and Unión Europea – NextGenerationEU. DE acknowledges support from: (1) a Beatriz Galindo senior fellowship (BG20/00224) from the Spanish Ministry of Science and Innovation, (2) projects PID2020-114414GB-100 and PID2020-113689GB-I00 financed by MCIN/AEI/10.13039/501100011033, (3) project P20-00334 financed by the Junta de Andalucía, (4) project A-FQM-510-UGR20 of the FEDER/Junta de Andalucía-Consejería de Transformación Económica, Industria, Conocimiento y Universidades. R.G.B. acknowledges financial support from the Severo Ochoa grant CEX2021-001131-S funded by MCIN/AEI/10.13039/501100011033 and to grant PID2022-141755NB-I00. AFM has received support from RYC2021-031099-I and PID2021-123313NA-I00 of MICIN/AEI/10.13039/501100011033/FEDER,UE, NextGenerationEU/PRT. TRL acknowledges support from Juan de la Cierva fellowship (IJC2020-043742-I). JFB acknowledges support from PID2022-140869NB-100. M.A.-F. acknowledges support from the Emergia program (EMERGIA20-38888) from Consejería de Universidad, Investigación e Innovación de la Junta de Andalucía. J.R. acknowledges financial support from the Spanish Ministry of Science and Innovation through the project PID2022-138896NB-C55. SDP acknowledges financial support from Juan de la Cierva Formación fellowship (FJC2021-047523-I) financed by MCIN/AEI/10.13039/501100011033 and by the European Union ‘NextGenerationEU’/PRTR, Ministerio de Economía y Competitividad under grants PID2019-107408GB-C44, PID2022-136598NB-C32, and is grateful to the Natural Sciences and Engineering Research Council of Canada, the Fonds de Recherche du Québec, and the Canada Foundation for Innovation for funding. This research made use of Astropy, a community-developed core Python (http://www.python.org) package for astronomy (Astropy Collaboration 2022); ipython (Pérez & Granger 2007); matplotlib (Hunter 2007); SciPy, a collection of open-source software for scientific computing in Python (Virtanen et al. 2020); and NumPy, a structure for efficient numerical computation (Harris et al. 2020). Funding for the SDSS and SDSS-II has been provided by the Alfred P. Sloan Foundation, the Participating Institutions, the National Science Foundation, the U.S. Department of Energy, the National Aeronautics and Space Administration, the Japanese Monbukagakusho, the Max Planck Society, and the Higher Education Funding Council for England. The SDSS website is http://www.sdss.org/

Results. We find that, on average, early-type galaxies in voids are approximately 10−20% smaller than their counterparts in denser environments, such as filaments, walls, and clusters, regardless of when they assembled their mass. Additionally, evidence suggests that the mass-size relation for the more massive void galaxies within the early-type sample exhibits a shallower slope, compared to galaxies in denser large-scale environments. In contrast, early-type galaxies in filaments, walls, and clusters exhibit a more consistent mass-size distribution. For stellar masses of log(M⋆/M⊙) = 9 − 10.5, late-type cluster galaxies are smaller and more concentrated than those in lower density environments, such as filaments, walls, and voids; whereas void and filament+wall galaxies exhibit similar size and concentration values. However, for galaxies with masses above 1010.5 M⊙, the sizes of void galaxies become comparable to those in clusters. The trend of smaller low-mass cluster galaxies is primarily driven by galaxies with T50 greater than 7 Gyr.

Conclusions. We conclude that the large-scale environment influences the mass-size relation of galaxies. Assuming that early-type galaxies undergo two growth phases, we find that they primarily grow their mass during the first phase of formation. In voids, the subsequent size growth from minor mergers is less pronounced. This is likely due to slower evolution and reduced minor merger activity or the fact that the void environment inherently has fewer accretion events, or even a combination of these effects. The change in slope for high-mass void galaxies suggests a lower rate of minor accretion. This trend is also evident in late-type void galaxies with masses above ≈1010.5 M⊙, where minor mergers contribute to their size growth. In contrast, late-type quenched cluster galaxies are smaller in size due to interactions within the cluster environment, with early infallers being more strongly affected by these environmental interactions. © The Authors 2025

Methods. We analysed the Petrosian R50 and R90 radii from SDSS DR16 images of a sample of ≈14 000 galaxies inhabiting cosmic voids, filaments and walls, and clusters, with a stellar mass range between 108.5 − 1011 M⊙. We investigated the mass-size relation with respect to the galaxy morphology, as well as with the star formation history (SFH), parametrised across a range of different timescales (T50, T70, and T90).

Context. The mass-size relation is a fundamental galaxy scaling relation that is intrinsically linked to galaxy formation and evolution. The physical processes involved in galaxy growth leave their particular imprint on the relation between the stellar or total mass and galaxy size.

Aims. We aim to explore the effect of the large-scale environment on the stellar mass-size relation using samples and a selection of added-value products from the Calar Alto Void Integral-field Treasury surveY (CAVITY) collaboration.

With funding from the Spanish government through the "Severo Ochoa Centre of Excellence" accreditation (CEX2021-001131-S).

Peer reviewed