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<blockquote style="position: relative; padding-left: 55px;"><section><a href="https://astrodon.social/users/kellylepo/statuses/111048159929663838">Kelly Lepo (kellylepo@astrodon.social)'s status on Wednesday, 13-Sep-2023 01:42:00 JST</a><a href="https://astrodon.social/@kellylepo" title="kellylepo@astrodon.social"><img src="https://gnusocial.jp/avatar/28639-48-20221116180105.webp" width="48" height="48" alt="Kelly Lepo" style="position: absolute; left: 0; top: 0;">Kelly Lepo</a><div><a href="https://astrodon.social/@kellylepo/111048065077290924" rel="in-reply-to">in reply to</a></div></section><article><p>Ok, actual science results from Andrey Kravtsov and GRUMPY. You can use a model designed for nearby dwarf galaxies and use it to fit the earliest galaxies. It works really well, as long as you have random, "bursty" star formation (which is reasonable).</p><p>No new physics required; very ancient galaxies follow the same rules as nearby galaxies. JWST has not disproven the Big Bang. <a href="https://astrodon.social/tags/JWSTYearOne" rel="tag">#JWSTYearOne</a></p></article><footer><a rel="bookmark" href="https://gnusocial.jp/conversation/2052104#notice-4026652">In conversation</a><time datetime="2023-09-13T01:42:00+09:00" title="Wednesday, 13-Sep-2023 01:42:00 JST">about a year ago</time> <span>from <span><a href="https://astrodon.social/@kellylepo/111048159929663838" rel="external" title="Sent from astrodon.social via ActivityPub">astrodon.social</a></span></span><a href="https://astrodon.social/@kellylepo/111048159929663838">permalink</a><h4>Attachments</h4><ol><li><label><a rel="external" href="https://gnusocial.jp/attachment/1511981">summary and implications» UV luminosity functions (LFs) of galaxies at redshifts z~5-16 can be reproduced with regular galaxy formation physics when stochasticity of star formation rate (SFR) is explicitly modeled. The same model reproduces z=0 dwarf galaxy properties well.» The level of the SFR stochasticity required to match.observed UV LFs at z~5-16 is consistent with that exhibited in galaxy formation simulations that resolve individual star-forming regions and include an efficient feedback model.» SFR stochasticity is expected to increase at z &gt; 10, but within reasonable limits and lower levels than indicated by previous studies. Feedback plays key role in driving the bursts.» Model results imply that1) z &gt; 10 galaxies are in smaller halos and have much lower SF efficiency than inferred using non-stochastic models; 2) UV LF and SFR-M* are expected to flatten significantly with increasing z at z &gt; 12 GRUMPY model and modeling of z=0 dwarf galaxies: ) Kravtsov &amp; Manwadkar 2022, MN 514, 2667 Manwadkar &amp; Kravtsov 2022, MN 516, 3944; Pan &amp; Kravisov, in prep. Modelling UVLFs: Kravtsov et al. 2023, in prep</a></label><br><a href="https://cdn.masto.host/astrodonsocial/media_attachments/files/111/048/140/434/226/512/original/9dbcf46f02c3f00d.png" rel="external">https://cdn.masto.host/astrodonsocial/media_attachments/files/111/048/140/434/226/512/original/9dbcf46f02c3f00d.png</a></li></ol></footer></blockquote>

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Kelly Lepo (kellylepo@astrodon.social)'s status on Wednesday, 13-Sep-2023 01:42:00 JST Kelly Lepo
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Ok, actual science results from Andrey Kravtsov and GRUMPY. You can use a model designed for nearby dwarf galaxies and use it to fit the earliest galaxies. It works really well, as long as you have random, "bursty" star formation (which is reasonable).
No new physics required; very ancient galaxies follow the same rules as nearby galaxies. JWST has not disproven the Big Bang. #JWSTYearOne
In conversationabout a year ago from astrodon.socialpermalink
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1. summary and implications » UV luminosity functions (LFs) of galaxies at redshifts z~5-16 can be reproduced with regular galaxy formation physics when stochasticity of star formation rate (SFR) is explicitly modeled. The same model reproduces z=0 dwarf galaxy properties well. » The level of the SFR stochasticity required to match.observed UV LFs at z~5-16 is consistent with that exhibited in galaxy formation simulations that resolve individual star-forming regions and include an efficient feedback model. » SFR stochasticity is expected to increase at z > 10, but within reasonable limits and lower levels than indicated by previous studies. Feedback plays key role in driving the bursts. » Model results imply that 1) z > 10 galaxies are in smaller halos and have much lower SF efficiency than inferred using non-stochastic models; 2) UV LF and SFR-M* are expected to flatten significantly with increasing z at z > 12 GRUMPY model and modeling of z=0 dwarf galaxies: ) Kravtsov & Manwadkar 2022, MN 514, 2667 Manwadkar & Kravtsov 2022, MN 516, 3944; Pan & Kravisov, in prep. Modelling UVLFs: Kravtsov et al. 2023, in prep
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