iiinova — where your digital self keeps evolving

Shaun Hotchkiss @justshaun.bsky.social · 21/09/2026

I'm such a rookie. Here's the registration link, by the way: cosmologyfromhome.com/registration/

cosmologyfromhome.com

Registration – Cosmology from Home

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Shaun Hotchkiss @justshaun.bsky.social · 21/09/2026

I'm such a rookie. Here's the registration link, by the way: cosmologyfromhome.com/registration/

cosmologyfromhome.com

Registration – Cosmology from Home

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Shaun Hotchkiss @justshaun.bsky.social · 21/09/2026

85 excellent reasons you should attend Cosmology from Home this year! cosmologyfromhome.com/2026-talks Discussions start tomorrow, talks (listed above) were released to participants last week.

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Shaun Hotchkiss @justshaun.bsky.social · 08/09/2026

Cosmology Paper: arxiv.org/abs/2609.05053 Host mass paper: arxiv.org/abs/2609.05321

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Shaun Hotchkiss @justshaun.bsky.social · 08/09/2026

"I don't see why they can't just combine Pantheon+ and DES-Dovekie and get even tighter dark energy constraints" Your wish is granted! Featuring Tamara Davis, Jason Lee & Ryan Camilleri youtu.be/KT-j65gRnOQ

youtu.be

Cosmology from Combining Pantheon+ and DES-Dovekie (Camilleri, Davis and Lee)

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 07/08/2026

Fascinated by recent evidence for evolving dark energy? But wondering what it all means for fundamental physics models? Cosmology Talks has you covered! Everything you need to know about single scalar field dark energy in 2026. (Carlos García-García & William Wolf) youtu.be/RbXqghcRv0U

youtu.be

Single Scalar Field Dark Energy: 2026 Status Report (García-García & Wolf)

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 29/07/2026

The latest Cosmology Talk! Low mass dark matter halos are to gravitational waves, as the atmosphere is to stars. And because of that, LISA might detect them! (lower than 10^4 M_sol 😲) Featuring Miguel Zumalacárregui, Juan Urrutia and Han Gil Choi youtu.be/a5lIDTDRo4c

youtu.be

Probing Low Mass Dark Matter Halos with LISA | Choi, Urrutia & Zumalacárregui

YouTube video by Cosmology Talks

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Swagat Saurav Mishra @primeval-arhsim.bsky.social · 12/06/2026

Hope you enjoy watching this latest release from 'Cosmology Talks' where Shaun & I discuss: What cosmological inference of evolving (including Phantom) Dark Energy Does & Does Not Imply - in the context of DESI BAO results and beyond. Based on my recent work on the arXiv.

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Shaun Hotchkiss @justshaun.bsky.social · 12/06/2026

Latest DESI (+CMB +SN) data got you spooked? Seeing ghosts and *phantoms*? Don't panic! @primeval-arhsim.bsky.social is here to reassure you: "No phantoms are needed by current observational cosmology" youtu.be/etp-uezMgdw

youtu.be

Phantom Dark Energy: What Cosmology Does and Does Not Imply (Swagat Mishra)

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 15/05/2026

Official announcement coming soon, O(weeks), with lists/descriptions of confirmed speakers/talks/content. If you register now, you can suggest topics/speakers to invite!

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Shaun Hotchkiss @justshaun.bsky.social · 15/05/2026

Fear not, cosmology masses. Cosmology from Home 2026 exists! In fact, it will run 21 Sept – 2 Oct and "early" registration just opened :-) cosmologyfromhome.com/registration/

cosmologyfromhome.com

Registration – Cosmology from Home

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Centre for Logic and Philosophy of Science (CLPS) @clpskuleuven.bsky.social · 03/05/2026

Problems of uniform probabilities arise in contemporary cosmology. Head over to the conversation that Sylvia Wenmackers had with @justshaun.bsky.social about her recent paper on the issue! 💻👇 www.youtube.com/watch?v=MBeS... 📄 www.sciencedirect.com/science/arti... #philsci #philsky #physics #HPS

youtube.com

New Probability Axioms Could Fix Cosmology's Multiverse (Partially) - Sylvia Wenmackers

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 25/04/2026

It's the moment that everyone on Bluesky is endlessly refreshing their timeline hoping for: The talk release of a "from Home" conference! Our knowledge of the universe is expanding at an accelerating rate... and Dark Energy from Home 2026 Talks just dropped.

youtube.com

Eric Linder - Dark Energy Phenomenology

YouTube video by Research Talks (from Home)

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Shaun Hotchkiss @justshaun.bsky.social · 05/03/2026

Confirmed speakers listed (and continuously updated) on homepage! darkenergy.discussingresearch.com

darkenergy.discussingresearch.com

Dark Energy from Home

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Shaun Hotchkiss @justshaun.bsky.social · 05/03/2026

Exciting! ........... Dark Energy from Home 2026 will be held from 21–24 April. Registration is now open: darkenergy.discussingresearch.com/registration Abstracts submitted by 24 March at 23:59 UTC will receive equal consideration. Later submissions will be reviewed at the organizers’ discretion.

darkenergy.discussingresearch.com

Registration – Dark Energy from Home

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Shaun Hotchkiss @justshaun.bsky.social · 03/03/2026

It's the day everyone on Bluesky looks forward to: The talk release day of a from Home conference! Early Universe from Home 2026 Talks just dropped. Check them out, there's lots of really interesting stuff going on.

youtube.com

Diederik Roest - Isocurvature modes during turns and their imprint on the CMB

YouTube video by Research Talks (from Home)

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Shaun Hotchkiss @justshaun.bsky.social · 11/02/2026

Stay tuned for updates regarding the first few themed discussions...

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Shaun Hotchkiss @justshaun.bsky.social · 11/02/2026

Discussions at Early Universe from Home kick off in just under two weeks, with talks released to participants in one week. Check out the updated list of speakers here: earlyuniverse.discussingresearch.com and register here: earlyuniverse.discussingresearch.com/registration/

earlyuniverse.discussingresearch.com

Early Universe from Home

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Shaun Hotchkiss @justshaun.bsky.social · 04/02/2026

"The evidence for dynamical dark energy relies too much on DESI's BAO, which is just one data set... " *Evidence for dynamical dark energy now seen with Dark Energy Survey BAO too* youtu.be/ukMQgHj6NMI

youtu.be

Dark Energy Survey - Combined cosmology from BAO + SN (+CMB) | Avila, Fernandez, Muir & Vincenzi)

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 27/01/2026

Can gravitational waves get gravitationally lensed? Yes! Have we observed any such events? Maybe!?😮😃 youtu.be/ZGqOpDTL8k4

youtu.be

A magnified and diffracted black hole merger (GW231123) | Miguel Zumalacarregui

YouTube video by Cosmology Talks

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Shaun Hotchkiss @justshaun.bsky.social · 11/11/2025

Want to know how to get at the non-linear cosmological scales to test modified gravity, using future large scale structure observations? Cosmology Talks has your back: youtu.be/nIdCpcObSVU

youtu.be

Cosmological Gravity on All Scales | Sankarshana Srinivasan

YouTube video by Cosmology Talks

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Sam Gregson @badboyofscience.bsky.social · 05/04/2025

Fantastic time discussing whether the latest blockbuster cosmology results really do show that Dark Energy is evolving! Brilliant explanations from @clairelamman.bsky.social , @tamarastro.bsky.social and @justshaun.bsky.social Check it out! Full talk: youtu.be/reNicLW2vpY?... 🧪⚛️

youtu.be

Is Dark Matter Evolving? Cosmologists Explain

YouTube video by Bad Boy of Science

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South Pole Telescope @sptelescope.bsky.social · 30/03/2025

Unfortunately it was pretty cloud during #Sunset this year at the South Pole, but our winterover Sim managed to catch this picture just before the weather got bad, with the moon over SPT! #southpole #Antarctica

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Astronomer Royal for Scotland | Catherine Heymans @astroroyalscot.bsky.social · 26/03/2025

🥳 It's paper day for the completed #ESO Kilo-Degree Survey. We end our journey with a consistent picture of #cosmology 😲 I've been co-leading KiDS for 12yrs & I'm so proud of what the team's achieved. If you're at the #Euclid meet, go to Angus Wright's talk @10am today!🔭 ℹ️: arxiv.org/pdf/2503.19441

$A two panel figure. The x-axis is omega_m, the fraction of matter in the Universe. The y-axis is S8 on the left and sigma_8 on the right. Both are measures of the 'clumpiness' of dark matter. The contours show that the KiDS data (two measurements using slightly different statistics, COSEBIs and Bandpowers) agree with the data from the Planck CMB survey.$

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Shaun Hotchkiss @justshaun.bsky.social · 26/03/2025

The Cosmology Tension Gods giveth and the Cosmology Tension Gods taketh away 🤷

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Shaun Hotchkiss @justshaun.bsky.social · 25/03/2025

Haha 😅, I'll let you know if Enrique from Universe 2845b has any great insights.

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Shaun Hotchkiss @justshaun.bsky.social · 25/03/2025

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Shaun Hotchkiss @justshaun.bsky.social · 25/03/2025

Rather appropriately, given this proliferation of "from Home" events, the next one to announce is: Multiverse from Home! I suspect discussion won't be hard to come by in this one 😅. multiverse.cosmodiscussion.com

multiverse.cosmodiscussion.com

Multiverse from Home

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Shaun Hotchkiss @justshaun.bsky.social · 25/03/2025

"Tabletops" in space might still be necessary sometimes though 😂.

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Shaun Hotchkiss @justshaun.bsky.social · 25/03/2025

Another "from Home" conference has launched (complete with the *perfect* banner image)... *Tabletop Scale Cosmology* Register now to discuss, and hear about, how you don't need giant telescopes and colliders to learn about the cosmos! tabletop.cosmodiscussion.com

tabletop.cosmodiscussion.com

Tabletop Scale Cosmology

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Shaun Hotchkiss @justshaun.bsky.social · 21/03/2025

There are certainly examples of groups revealing results too soon, before double/triple checking possible interpretations 😅.

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Shaun Hotchkiss @justshaun.bsky.social · 21/03/2025

I think I do disagree on the scaffolding metaphor, but I'm not sure my disagreeing is interesting 😅. I'd liken it more to halftime at a sports game, or showing partial counts on election day (In terms of how interesting people find it, not how feasible it is to do without compromising other things)

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Shaun Hotchkiss @justshaun.bsky.social · 21/03/2025

I don't *think* I disagree with any/most of this. Me calling it the "dream" did mean to imply it isn't necessarily feasible, partially for reasons you point out. It can still be a dream to aspire to get *closer* to, without compromising too much on other important things of value.

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Shaun Hotchkiss @justshaun.bsky.social · 21/03/2025

One last thing I realised after writing everything above... Going from ΛCDM to "wCDM", with w0 \neq -1 and wa \neq 0 doesn't, as far as I know, break any other observation (yet!) So many other solutions to tensions/problems within ΛCDM fix one thing, only to bust something else.

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Shaun Hotchkiss @justshaun.bsky.social · 20/03/2025

Ah, cool! You should polish them and make them public somewhere 😁.

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Shaun Hotchkiss @justshaun.bsky.social · 20/03/2025

"where the dust will settle" 👀 dangerous choice of language in astronomy 😅

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Shaun Hotchkiss @justshaun.bsky.social · 20/03/2025

This is really cool. I'd love for something like this to be recorded and shared afterwards so that the rest of the world can re-live the excitement. (The dream would be one day for the scientists and public to be unblinded simultaneously, with expert commentary as it unfolds!)

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Sesh Nadathur @seshnadathur.bsky.social · 20/03/2025

A nice blog post by Gillian Beltz-Mohrmann about the DESI "unblinding" event last year, the excitement and the reactions: www.desi.lbl.gov/2025/03/19/a...

desi.lbl.gov

At the Big Reveal: DESI’s December 2024 Unblinding Results

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Claire Lamman @clairelamman.bsky.social · 20/03/2025

DESI's DR2 BAO results are out!! TL;DR... 1/n @desisurvey.bsky.social

A blocky lambda symbol crumbles as it is pulled apart by creatures representing Baryon Acoustic Oscillations, the Cosmic Microwave Background, and supernovae. Caption reads "something has to give..." Credit: Claire Lamman

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Héctor Gil Marín @cosmonautico.bsky.social · 20/03/2025

🔊 New BAO analysis from the 3-year observations (DR2). Long story short, as follows. 1. DESI alone is consistent with LCDM. 👉 Boring 2. DESI and Planck have a 2.3 discrepancy in Ωm-H0rd plane. 👉Interesting.

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Shaun Hotchkiss @justshaun.bsky.social · 19/03/2025

Yeah, I agree with that framing too. It does seem to look like wo,wa though (e.g. from the binned w(z) plot). Now that at least the yr1 data is public I'm looking forward to which a posteriori model floats to the top of the a posteriori best fit pile 😅. (Hopefully one well motivated one rises up!)

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Shaun Hotchkiss @justshaun.bsky.social · 19/03/2025

w0,wa is of course just a parameterisation, but it seems to be a genuinely good one for the observations we've made of this universe in 2025 🤷

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Shaun Hotchkiss @justshaun.bsky.social · 19/03/2025

And finally, the best fit combined value of wo,wa isn't somehow in tension with what each individual probe wants, it's more or less a consistent story of wo,wa-ness in the data 🤷

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Shaun Hotchkiss @justshaun.bsky.social · 19/03/2025

In ΛCDM there seems to be a genuine "Omega_m" tension between probes... in wo,wa it goes away... (see DES Y5 vs DESI DR2 BAO)

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Shaun Hotchkiss @justshaun.bsky.social · 19/03/2025

Not to mention that neutrinos masses in ΛCDM with neutrinos masses looks very suspicious, because it is starting to rule out the lower bound from particles physics... But in wo,wa it goes back to being all fine...

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