B Questions about a paper on reconciling JWST and HST data

[Cerenkov]

TL;DR Summary

https://astrobites.org/2024/02/17/cosmic-inconsistencies/
https://arxiv.org/abs/2305.07049
Insights from HST into Ultra-Massive Galaxies and Early-Universe Cosmology

Hello.


I came across this article, https://astrobites.org/2024/02/17/cosmic-inconsistencies/ and followed the link to this paper, https://arxiv.org/abs/2305.07049 Insights from HST into Ultra-Massive Galaxies and Early-Universe Cosmology and have read the .pdf

For the moment I have just one request.

Could the conclusion that the authors make please be explained to me in Basic terms so that I can gain a better understanding of what is meant? I would like to better understand the UV galaxy luminosity function and also what the authors mean when they refer to a cosmological solution to the JWST abundance problem.

Thank you for any help given,


Cerenkov.

​

 

[pbuk]

Could the conclusion that the authors make please be explained to me in Basic terms.

The article you linked does this well:

The findings from JWST observations have presented a challenge to the existing models of galaxy formation and early-Universe cosmology that led to a reevaluation of our cosmological model. Today’s paper demonstrated that any modifications to the cosmological model enough to explain the JWST data would be in conflict with the well-established HST data. Their analysis implies that a cosmological solution to the JWST mass excess problem might not be the most favored. Moving forward, the extensively validated HST data emerges as a crucial tool for interpreting future observations, signalling the importance of leveraging its well-established insights in shaping our understanding of the universe.

Edit: or even more basic terms:

Changing the ΛCDM model so that it predicts more massive galaxies at high redshifts is a bad idea because the changed model contradicts too many other observations.

I would like to better understand the UV galaxy luminosity function

I don't think cherry-picking technical subjects is a good way to learn (one lacks the necessary background understanding and context), but if you insist the seminal paper is Charles C. Steidel et al 1999 ApJ 519 1.

also what the authors mean when they refer to a cosmological solution to the JWST abundance problem

This refers to changing the ΛCDM model so that it predicts more massive galaxies at high redshifts.

Thank you for any help given,

Although the Astrobites article is good, you might find JWST Sees More Galaxies than Expected more accessible.

 

[Cerenkov]

Many thanks, pbuk.

You were right, btw. Your linked article was just what I needed to read to understand this better.


Thanks again,

Cerenkov.

 

[Jaime Rudas]

Regarding the discrepancy between the abundance of massive galaxies in the early universe and the ΛCDM cosmological model, this other paper presents a possible explanation for this abundance within the framework of the ΛCDM model.

 

[Cerenkov]

Many thanks for this, Jaime.

Cerenkov.