Joe Zuntz
@joezuntz.bsky.social
Professor of Cosmology at the University of Edinburgh.
Reposted by Joe Zuntz
First paper from my PhD student Yun-Hao Zhang! arxiv.org/abs/2508.20903 While preparing to put together data for another project, Yun-Hao came up with a way to improve a technique from our colleagues for galaxy redshift estimation. This is the first of two papers laying out and testing the method
Improved photometric redshift estimations through self-organising map-based data augmentation
We introduce a framework for the enhanced estimation of photometric redshifts using Self-Organising Maps (SOMs). Our method projects galaxy Spectral Energy Distributions (SEDs) onto a two-dimensional ...
arxiv.org
September 1, 2025 at 7:42 AM
First paper from my PhD student Yun-Hao Zhang! arxiv.org/abs/2508.20903 While preparing to put together data for another project, Yun-Hao came up with a way to improve a technique from our colleagues for galaxy redshift estimation. This is the first of two papers laying out and testing the method
So there's about a seventeen different likelihood codes for the Planck CMB mission. Can anyone explain to me which are 1) currently widely useful, 2) handy to keep to compare old results to, 3) obsolete?
August 20, 2025 at 8:47 AM
So there's about a seventeen different likelihood codes for the Planck CMB mission. Can anyone explain to me which are 1) currently widely useful, 2) handy to keep to compare old results to, 3) obsolete?
Reposted by Joe Zuntz
We’d planned to return for #NAM2025 but the conference wifi won’t display this account. Or the program. Or anything about NAM. Is the conference itself now unofficial @robertmassey.bsky.social ?
July 7, 2025 at 8:44 AM
We’d planned to return for #NAM2025 but the conference wifi won’t display this account. Or the program. Or anything about NAM. Is the conference itself now unofficial @robertmassey.bsky.social ?
Just arrived for #NAM2025. Very nice to be here, and seen people I know already - hi @ritatojeiro.bsky.social! Weirdly I can't seem to get to the conference even website though.
July 6, 2025 at 4:25 PM
Just arrived for #NAM2025. Very nice to be here, and seen people I know already - hi @ritatojeiro.bsky.social! Weirdly I can't seem to get to the conference even website though.
Reposted by Joe Zuntz
There is a concept called "stolen valour", where people pretend to be military to get prestige or free stuff.
I think in science and other discourse we see a lot of "stolen rigour": authors borrow a concept from maths/stats/some "hard" science, and use it to give authority where it isn't deserved.
I think in science and other discourse we see a lot of "stolen rigour": authors borrow a concept from maths/stats/some "hard" science, and use it to give authority where it isn't deserved.
May 26, 2025 at 9:37 AM
There is a concept called "stolen valour", where people pretend to be military to get prestige or free stuff.
I think in science and other discourse we see a lot of "stolen rigour": authors borrow a concept from maths/stats/some "hard" science, and use it to give authority where it isn't deserved.
I think in science and other discourse we see a lot of "stolen rigour": authors borrow a concept from maths/stats/some "hard" science, and use it to give authority where it isn't deserved.
When you're writing exam questions you really have to go through them like a lawyer and see if you can misconstrue a question in any way at all. Any possible interpretation, no matter how sensible, at least one student will use!
May 15, 2025 at 10:18 AM
When you're writing exam questions you really have to go through them like a lawyer and see if you can misconstrue a question in any way at all. Any possible interpretation, no matter how sensible, at least one student will use!
If you read the first letter of every paragraph it spells out "George was right".
🥳 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
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
March 26, 2025 at 2:02 PM
If you read the first letter of every paragraph it spells out "George was right".
Reposted by Joe Zuntz
I am looking for a PhD student to work on beyond 2-point statistics for galaxy clustering & weak lensing as part of my Grant "Probing cosmic large-scale structure beyond the average" Details: uni-bielefeld.hr4you.org/job/view/417... Please share in your networks and encourage candidates to apply!
Research position (PhD student) in the field of cosmology
The Cosmology and Astroparticle Physics group investigates the formation and evolution of large-scale structures in the Universe, the nature of dark m...
uni-bielefeld.hr4you.org
March 24, 2025 at 7:43 AM
I am looking for a PhD student to work on beyond 2-point statistics for galaxy clustering & weak lensing as part of my Grant "Probing cosmic large-scale structure beyond the average" Details: uni-bielefeld.hr4you.org/job/view/417... Please share in your networks and encourage candidates to apply!
Reposted by Joe Zuntz
New Publication at the Open Journal of Astrophysics: "Baryon-free S_8 tension with stage IV cosmic shear surveys" by Ottavia Truttero, Joe Zuntz, Alkistis Pourtsidou and Naomi Robertson (University of Edinburgh, UK).
astro.theoj.org/article/1299... IV cosmic shear surveys"
astro.theoj.org/article/1299... IV cosmic shear surveys"
Baryon-free $S_8$ tension with Stage IV cosmic shear surveys | Published in The Open Journal of Astrophysics
By Ottavia Truttero, Joe Zuntz & 2 more. A study of the effect of vbaryonic feedback oin the dtermination of cosmological parameters and the possibility of using large-scale clustering information onl...
astro.theoj.org
February 24, 2025 at 8:58 AM
New Publication at the Open Journal of Astrophysics: "Baryon-free S_8 tension with stage IV cosmic shear surveys" by Ottavia Truttero, Joe Zuntz, Alkistis Pourtsidou and Naomi Robertson (University of Edinburgh, UK).
astro.theoj.org/article/1299... IV cosmic shear surveys"
astro.theoj.org/article/1299... IV cosmic shear surveys"
Reposted by Joe Zuntz
First 2025 release of GLASS is out: github.com/glass-dev/gl...
It comes with a big change that allows you to easily create FLASK-like simulations from a set of n(z) without simulating the entire lightcone. This isn’t usually the best way to go, but can sometimes be.
It comes with a big change that allows you to easily create FLASK-like simulations from a set of n(z) without simulating the entire lightcone. This isn’t usually the best way to go, but can sometimes be.
Release glass 2025.1 · glass-dev/glass
First 2025 release of GLASS.
Release note
Changelog
Full list of commits
github.com
February 23, 2025 at 11:54 AM
First 2025 release of GLASS is out: github.com/glass-dev/gl...
It comes with a big change that allows you to easily create FLASK-like simulations from a set of n(z) without simulating the entire lightcone. This isn’t usually the best way to go, but can sometimes be.
It comes with a big change that allows you to easily create FLASK-like simulations from a set of n(z) without simulating the entire lightcone. This isn’t usually the best way to go, but can sometimes be.
[1/3] The old joke TV listings site TVGoHome once included a movie "Die Hard Through A Cow", where "Die Hard" was shown to a dairy cow and its brainwaves scanned to reconstruct the movie, as filtered through the bovine mind.
January 31, 2025 at 8:58 AM
[1/3] The old joke TV listings site TVGoHome once included a movie "Die Hard Through A Cow", where "Die Hard" was shown to a dairy cow and its brainwaves scanned to reconstruct the movie, as filtered through the bovine mind.
Reposted by Joe Zuntz
It's a crazy world where it is cheaper to see Iron Maiden with a VIP ticket than to attend the Euclid Consortium Meeting >.<
January 11, 2025 at 12:03 PM
It's a crazy world where it is cheaper to see Iron Maiden with a VIP ticket than to attend the Euclid Consortium Meeting >.<
Reposted by Joe Zuntz
Are you on the Postdoc market and excited about early science with @vrubinobs.bsky.social, especially time domain, solar system, near field cosmology, or SETI? Well check out the @dirac-institute.bsky.social fellowship position that just got posted!
apply.interfolio.com/158267
apply.interfolio.com/158267
Apply - Interfolio
{{$ctrl.$state.data.pageTitle}} - Apply - Interfolio
apply.interfolio.com
November 25, 2024 at 9:01 PM
Are you on the Postdoc market and excited about early science with @vrubinobs.bsky.social, especially time domain, solar system, near field cosmology, or SETI? Well check out the @dirac-institute.bsky.social fellowship position that just got posted!
apply.interfolio.com/158267
apply.interfolio.com/158267
Preparing for our new Dark Universe undergraduate course next semester, I'm putting together various animations and illustrations. Here's a few of my favourite ...
November 15, 2024 at 12:05 PM
Preparing for our new Dark Universe undergraduate course next semester, I'm putting together various animations and illustrations. Here's a few of my favourite ...
Reposted by Joe Zuntz
Photons, meet the Commissioning Camera 🤝
On October 24, Rubin staff successfully completed the first end-to-end on-sky test of the full telescope system using the testing camera — from capturing the sky to transferring data to SLAC! 🔭🧪
🔗: https://rubinobservatory.org/news/test-camera-sees-sky
On October 24, Rubin staff successfully completed the first end-to-end on-sky test of the full telescope system using the testing camera — from capturing the sky to transferring data to SLAC! 🔭🧪
🔗: https://rubinobservatory.org/news/test-camera-sees-sky
October 29, 2024 at 8:43 AM
Photons, meet the Commissioning Camera 🤝
On October 24, Rubin staff successfully completed the first end-to-end on-sky test of the full telescope system using the testing camera — from capturing the sky to transferring data to SLAC! 🔭🧪
🔗: https://rubinobservatory.org/news/test-camera-sees-sky
On October 24, Rubin staff successfully completed the first end-to-end on-sky test of the full telescope system using the testing camera — from capturing the sky to transferring data to SLAC! 🔭🧪
🔗: https://rubinobservatory.org/news/test-camera-sees-sky
First paper by my student Ottavia Truttero! We explore using very conservative scale cuts in LSST weak lensing to completely cut out baryonic effects of the power spectrum. Stage IV power is so high that we may still detect S8 tension with only large-scale data arxiv.org/abs/2410.18191
Baryon-free $S_8$ tension with Stage IV cosmic shear surveys
Accurately modelling matter power spectrum effects at small scales, such as baryonic feedback, is essential to avoid significant bias in the estimation of cosmological parameters with cosmic shear. Ho...
arxiv.org
October 25, 2024 at 8:26 AM
First paper by my student Ottavia Truttero! We explore using very conservative scale cuts in LSST weak lensing to completely cut out baryonic effects of the power spectrum. Stage IV power is so high that we may still detect S8 tension with only large-scale data arxiv.org/abs/2410.18191
Reposted by Joe Zuntz
Crazy to read about the training programme for the 100m Olympic runners. Apparently they start very gradually, running only 1 or 2m per week, then building up to 50m the week before the race.
August 5, 2024 at 1:33 PM
Crazy to read about the training programme for the 100m Olympic runners. Apparently they start very gradually, running only 1 or 2m per week, then building up to 50m the week before the race.
It's very nice to be able to share that I've been promoted to Professor of Cosmology at the University of Edinburgh.
August 1, 2024 at 9:24 AM
It's very nice to be able to share that I've been promoted to Professor of Cosmology at the University of Edinburgh.
Message to Gen Z: I know your entire conception of human culture is built around photos with captions on, but when you're sending an error message to get help with some software, please don't send a screenshot of text. It's slower than copy/pasting anyway.
July 26, 2024 at 8:50 AM
Message to Gen Z: I know your entire conception of human culture is built around photos with captions on, but when you're sending an error message to get help with some software, please don't send a screenshot of text. It's slower than copy/pasting anyway.
I'm in the middle of a fascinating teaching project: designing a second course for physics students in programming and computer modelling, but incorporating and allowing use of AI assistants in their work.
July 2, 2024 at 8:26 AM
I'm in the middle of a fascinating teaching project: designing a second course for physics students in programming and computer modelling, but incorporating and allowing use of AI assistants in their work.
Reposted by Joe Zuntz
Reposted by Joe Zuntz
New Publication at the Open Journal of Astrophysics: "Comparing Mass Mapping Reconstruction Methods with Minkowski Functionals" by Nisha Grewal (U. Edinburgh, UK), Joe Zuntz (U Ediburgh, UK) and Tilman Tröster (ETH Zurich, Switzerland)
astro.theoj.org/article/1203...
astro.theoj.org/article/1203...
Comparing Mass Mapping Reconstruction Methods with Minkowski Functionals | Published in The Open Journal of Astrophysics
By Nisha Grewal, Joe Zuntz & 1 more. Quantifying the accuracy, precision and efficiency of lensing reconstruction methods using topological characteristics.
astro.theoj.org
June 24, 2024 at 9:23 AM
New Publication at the Open Journal of Astrophysics: "Comparing Mass Mapping Reconstruction Methods with Minkowski Functionals" by Nisha Grewal (U. Edinburgh, UK), Joe Zuntz (U Ediburgh, UK) and Tilman Tröster (ETH Zurich, Switzerland)
astro.theoj.org/article/1203...
astro.theoj.org/article/1203...
Back to the office today after 4 months of paternity leave! Wonder if I'll have forgotten how to do stuff. First task is to clear out about 1000 emails.
May 24, 2024 at 7:07 AM
Back to the office today after 4 months of paternity leave! Wonder if I'll have forgotten how to do stuff. First task is to clear out about 1000 emails.