The Cosmic Rush Hour: Rapid Formation of Bright, Massive, Disky, Star-Forming Galaxies as Signatures of Early-Universe Physics
Fuente:
arXiv
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866915509701705728 |
|---|---|
| author | Shen, Xuejian Zier, Oliver Vogelsberger, Mark Boylan-Kolchin, Michael Hernquist, Lars Tacchella, Sandro Naidu, Rohan P. |
| author_facet | Shen, Xuejian Zier, Oliver Vogelsberger, Mark Boylan-Kolchin, Michael Hernquist, Lars Tacchella, Sandro Naidu, Rohan P. |
| contents | Early JWST observations have revealed a high-redshift universe more vibrant than predicted by canonical galaxy-formation models within $Λ$CDM, showing an excess of ultraviolet(UV)-bright, massive, and morphologically mature galaxies. Departures from $Λ$CDM prior to recombination can imprint signatures on non-linear structure formation at high redshift. In this paper, we investigate one such scenario - Early Dark Energy, originally proposed to resolve the Hubble tension - and its implications for these high-redshift challenges. We present the first large-scale cosmological hydrodynamic simulations of these models. Modifications to the pre-recombination expansion history accelerate early structure formation and produce UV luminosity and stellar mass functions in excellent agreement with JWST measurements, requiring essentially no additional calibrations. Predictions converge to $Λ$CDM at lower redshifts ($z \lesssim 3$), thereby preserving all successes of $Λ$CDM. This model also accelerates the emergence of stellar and gaseous disks, increasing their number densities by $\sim 0.5$ dex at $z\simeq 6$-7, primarily due to the higher abundance of massive galaxies. Taken together, these results demonstrate how early-universe physics can simultaneously reconcile multiple high-redshift challenges and the Hubble tension while retaining the core achievements of $Λ$CDM. This opens a pathway to constraining a broad class of beyond-$Λ$CDM models with forthcoming observations. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2509_19427 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | The Cosmic Rush Hour: Rapid Formation of Bright, Massive, Disky, Star-Forming Galaxies as Signatures of Early-Universe Physics Shen, Xuejian Zier, Oliver Vogelsberger, Mark Boylan-Kolchin, Michael Hernquist, Lars Tacchella, Sandro Naidu, Rohan P. Astrophysics of Galaxies Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology Early JWST observations have revealed a high-redshift universe more vibrant than predicted by canonical galaxy-formation models within $Λ$CDM, showing an excess of ultraviolet(UV)-bright, massive, and morphologically mature galaxies. Departures from $Λ$CDM prior to recombination can imprint signatures on non-linear structure formation at high redshift. In this paper, we investigate one such scenario - Early Dark Energy, originally proposed to resolve the Hubble tension - and its implications for these high-redshift challenges. We present the first large-scale cosmological hydrodynamic simulations of these models. Modifications to the pre-recombination expansion history accelerate early structure formation and produce UV luminosity and stellar mass functions in excellent agreement with JWST measurements, requiring essentially no additional calibrations. Predictions converge to $Λ$CDM at lower redshifts ($z \lesssim 3$), thereby preserving all successes of $Λ$CDM. This model also accelerates the emergence of stellar and gaseous disks, increasing their number densities by $\sim 0.5$ dex at $z\simeq 6$-7, primarily due to the higher abundance of massive galaxies. Taken together, these results demonstrate how early-universe physics can simultaneously reconcile multiple high-redshift challenges and the Hubble tension while retaining the core achievements of $Λ$CDM. This opens a pathway to constraining a broad class of beyond-$Λ$CDM models with forthcoming observations. |
| title | The Cosmic Rush Hour: Rapid Formation of Bright, Massive, Disky, Star-Forming Galaxies as Signatures of Early-Universe Physics |
| topic | Astrophysics of Galaxies Cosmology and Nongalactic Astrophysics High Energy Physics - Phenomenology |
| url | https://arxiv.org/abs/2509.19427 |