Ulrich Pennig
@pennigulrich.bsky.social
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Senior Lecturer in Algebra and Topology at Cardiff University. All views are my own.
Happy (topological) Valentines Day!
2 days ago
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Oliver
6 days ago
Well done Bangor University Debating Society
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This sounds like a good summary:
www.youtube.com/watch?app=de...
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Why Replacing Developers with AI is Going Horribly Wrong
YouTube video by Mackard
https://www.youtube.com/watch?app=desktop&v=WfjGZCuxl-U
8 days ago
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Another website that future historians will find helpful (as we do not seem to be able to learn at our current stage):
incidentdatabase.ai
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Welcome to the Artificial Intelligence Incident Database
The starting point for information about the AI Incident Database
https://incidentdatabase.ai
10 days ago
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Bastian Grossenbacher-Rieck
17 days ago
Have some (applied) topology research you want to share with the world? Consider adding it to 🍩DONUT🍩, our Database of Original & Non-Theoretical Uses of Topology. Great intro by Barbara Giunti:
www.youtube.com/watch?v=eQ_5...
🏠
donut.topology.rocks
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Barbara Giunti: DONUT - Database of Original Non-theoretical Uses of Topology
YouTube video by Applied Algebraic Topology Network
https://www.youtube.com/watch?v=eQ_5ScYmS7g
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Prof Christina Pagel
23 days ago
It's only 3 weeks since the US invaded Venezuela, captured its president and appropriated its oil. And yet it's barely been in the news for last week or two cos of all the other new shit. What a world. makes it hard for me &
@sandylaping.bsky.social
to stay on top of
www.trumpactiontracker.info
!
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https://www.trumpactiontracker.info/
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Blue 🌸
about 1 year ago
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KZ-Gedenkstätte Neuengamme
about 1 month ago
Gedenkstätten, Lernorte, Museen und Archive haben einen offenen Brief veröffentlicht: „𝗞𝗼𝗻𝘀𝗲𝗾𝘂𝗲𝗻𝘁𝗲𝘀 𝗩𝗼𝗿𝗴𝗲𝗵𝗲𝗻 𝗴𝗲𝗴𝗲𝗻 𝗞𝗜-𝗴𝗲𝗻𝗲𝗿𝗶𝗲𝗿𝘁𝗲 𝗛𝗼𝗹𝗼𝗰𝗮𝘂𝘀𝘁-𝗩𝗲𝗿𝗳ä𝗹𝘀𝗰𝗵𝘂𝗻𝗴𝗲𝗻 𝗮𝘂𝗳 𝗦𝗼𝗰𝗶𝗮𝗹 𝗠𝗲𝗱𝗶𝗮-𝗣𝗹𝗮𝘁𝘁𝗳𝗼𝗿𝗺𝗲𝗻“. Hier geht es zum ganzen Text:
www.gedenkstaetten-hamburg.de/de/aktuelles...
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Do you love operator algebras? Join us in the Abacws Building at Cardiff University for the next meeting of our research network Operator Algebras in the South of the UK in Cardiff from 19th to 20th March 2026. Details can be found on our homepage
sites.google.com/view/operato...
#Maths
#Research
about 1 month ago
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🇨🇦 🇺🇸 Zoë Keating
about 1 month ago
Would you like 30 mins that has nothing to do with any of the big important things happening out there? Here is a performance and interview for Vermont’s wonderful show Across the Fence. It aired on Christmas Day but I was mostly offline and forgot to post about it.
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12/25/25 Music for the Holidays with cellist and composer Zoe Keating
YouTube video by Across the Fence
https://www.youtube.com/watch?v=qvqLVeS31R8
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I have been following
@israellai.bsky.social
's journey to Learning Welsh. Now he wants to do the British Citizenship Test in Welsh, which seems to be quite difficult:
www.youtube.com/watch?v=JYFu...
#Welsh
#Wales
#LearningWelsh
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About the Welsh Citizenship Test Situation...
YouTube video by Rhapsody in Lingo
https://www.youtube.com/watch?v=JYFu2gY-Nl0
about 2 months ago
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NationCymru
about 2 months ago
Cardiff University students are demanding that the university authorities answer a series of searching questions following a traumatic year in which more than 1,800 academics were originally put ‘in scope’ for redundancy ✍️Martin Shipton
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Students call on Cardiff University to 'open the books' as cuts concerns continue
Martin Shipton Cardiff University students are demanding that the university authorities answer a series of searching questions following a traumatic year in which more than 1,800 academics were origi...
https://wp.me/p8Mk4U-1bH7
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Oh. My. God. I reached room 46...
about 2 months ago
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Waseda University in Tokyo is bidding to become the location for the ICM in 2030.
www.youtube.com/watch?v=FeRg...
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Bid for ICM2030 in Japan
YouTube video by icm2030bid
https://www.youtube.com/watch?v=FeRgzV0lzK8
about 2 months ago
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I am happy to share that our article "Spectral sequence computation of higher twisted K-groups of SU(n)" has now been published in Communications of the American Mathematical Society. 🎉
doi.org/10.1090/cams...
#Mathematics
#KTheory
#OperatorAlgebras
#Research
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AMS :: Communications of the American Mathematical Society
https://doi.org/10.1090/cams/60
about 2 months ago
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Senator Bernie Sanders
2 months ago
I will be pushing for a moratorium on the construction of data centers that are powering the unregulated sprint to develop & deploy AI. The moratorium will give democracy a chance to catch up, and ensure that the benefits of technology work for all of us, not just the 1%.
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It's Time for a Moratorium on Data Centers | Sen. Bernie Sanders
YouTube video by Senator Bernie Sanders
https://youtu.be/f40SFNcTOXo?si=j-FlGZMt-V4sr7Wx
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This is an excellent article. A lot of it reads painfully familiar.
www.currentaffairs.org/news/ai-is-d...
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AI is Destroying the University and Learning Itself
Students use AI to write papers, professors use AI to grade them, degrees become meaningless, and tech companies make fortunes. Welcome to the death of higher education.
https://www.currentaffairs.org/news/ai-is-destroying-the-university-and-learning-itself
2 months ago
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Will Hayward - Wales Journo
3 months ago
We have written a special report looking at the people behind Reform in Wales. This was a bizarre piece to write.
willhaywardwales.substack.com/p/special-re...
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Special report: Who are Reform in Wales?
We dived into the wild world of Reform UK in Cymru
https://willhaywardwales.substack.com/p/special-report-who-are-reform-in
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People Make Games reporting (in their usual excellent way) about the situation at Rockstar Games:
www.youtube.com/watch?v=c9nO...
and the follow-up
www.youtube.com/watch?v=8TvW...
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The Rockstar Workers Fired Before They Could Finish GTA 6
YouTube video by People Make Games
https://www.youtube.com/watch?v=c9nOwjeznjI
3 months ago
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Excited to share details about this upcoming one-day workshop bringing together leading researchers in operator algebras and related fields! - on Friday, 21st November 2025 - in the Fry Building, School of Mathematics, University of Bristol For details see:
sites.google.com/view/operato...
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LinkedIn
This link will take you to a page that’s not on LinkedIn
https://lnkd.in/ew9B5QNH
3 months ago
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Dave Richeson
4 months ago
In case anyone wants to make some of these boards, I put the laser-cutter templates on my blog.
divisbyzero.com/2025/11/01/a...
add a skeleton here at some point
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Matthias Eberl
5 months ago
Full length video here, 9:01 minutes long - amazing work
@ledbydonkeys.org
.
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Trump & Epstein on Windsor castle #fyp
TikTok video by Led By Donkeys
https://www.tiktok.com/@ledbydonkeys/video/7550942110350888214
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'Meta CEO Mark Zuckerberg has told analysts that people without smart glasses may one day be at a "significant cognitive disadvantage" compared to those who do use the tech'
add a skeleton here at some point
5 months ago
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Today was the final day of the 38th British Topology Meeting. It was fun! Great to see so many young people in the field and hear all the recent developments.
5 months ago
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Ladies and Gentlemen! Elle Cordova:
www.youtube.com/shorts/AYm9w...
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For our scientists
YouTube video by Elle Cordova
https://www.youtube.com/shorts/AYm9w6W5B-E
5 months ago
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David Jekel
5 months ago
Here is Erisa today at the Gorom refugee settlement. Please share the fundraiser so I can send him more support (in addition to what I have sent personally)
www.gofundme.com/f/aid-for-er...
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The first step in a project that is dear to my heart has now appeared on the arXiv (
arxiv.org/abs/2509.04134
). In it we develop a unified framework describing how different notions of symmetries of operator algebras are interlinked. We reveal interesting connections with homotopy theory as well.
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G-kernels and Crossed Modules
We develop a unified framework based on topological crossed modules for various lifting obstructions for $Γ$-kernels. It allows us to identify actions, cocycle actions and $Γ$-kernels up to their natu...
https://arxiv.org/abs/2509.04134
5 months ago
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Matthias Eberl
6 months ago
Just a member of the UK parliament asking me, my family, my neighbours, my colleagues, school teachers, friends and a large proportion of the NHS to leave the country. And the richest person in the world endorsing the message.
add a skeleton here at some point
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Otto English
6 months ago
I've a feeling Mr Farage might very much be regretting his trip... round about ... Now 👇
add a skeleton here at some point
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Chris Bratt
6 months ago
Okay, big breath... After more than two years since we published our last documentary on the topic, it's time we returned to Disco Elysium:
www.youtube.com/watch?v=lZEA...
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We Need to Talk about Disco Elysium, Again
YouTube video by People Make Games
https://www.youtube.com/watch?v=lZEAs6M1wts
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Christian Wolf
6 months ago
arstechnica.com/science/2025...
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Bluesky now platform of choice for science community
It’s not just you. Survey says: “Twitter sucks now and all the cool kids are moving to Bluesky”…
https://arstechnica.com/science/2025/08/more-scientists-choose-bluesky-over-twitter/
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London Mathematical Society
6 months ago
We're delighted to be once again co-hosting the Black Heroes of Mathematics Conference, taking place at @DeMorganHouse (and online) on 1 and 2 October. Register now ➡️
www.lms.ac.uk/events/black...
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theHigherGeometer
6 months ago
We are advertising a Level D/E position in Pure Maths at University of Adelaide (for non-Oz-initiated: E=full Prof, D=one step down).
https://careers.adelaide.edu.au/cw/en/job/517088/associate-professor-professor-de-pure-mathematics
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Alexander Kasprzyk
6 months ago
Alvaro Torras Casas (Cardiff) speaking on "Dataset comparison using persistent homology morphisms" at our
#MachineLearning
#Math
seminar back in May 2023.
#MathSky
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Alvaro Torras Casas (Cardiff)
Alvaro Torras Casas (Cardiff)31 May 2023"Dataset comparison using persistent homology morphisms"Persistent homology summarizes geometrical information of dat...
https://www.youtube.com/watch?v=PBjJJWAjaP8
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Adi Onus
7 months ago
This November the place to be is Brisbane! Registration is now open for QTMC here
queertransmath.com
- be sure to sign up and tell your friends!
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Ulrich Pennig
Eva Soulu 🌿
6 months ago
Today is my birthday! Could you, please, share my art, it is the best gift an artist can get 💖
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Endless Screaming
7 months ago
AAAAAHHHHH
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Izabella Laba 🇨🇦
7 months ago
Are we still having the ICM in Philly next year?
add a skeleton here at some point
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Quick reminder that registrations for the 38th British Topology Meeting in Cardiff are still open!
#topology
#MathSky
#AcademicSky
add a skeleton here at some point
7 months ago
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Alexander Kasprzyk
7 months ago
The devastating funding cuts to mathematics research in the US will cut-short the careers of a generation of mathematicians. It really is disgraceful, and unbelievably shortsighted.
#MathSky
www.scientificamerican.com/article/can-...
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Math Is Quietly in Crisis over NSF Funding Cuts
A 72 percent reduction in federal funding is devastating to math research. The American Mathematical Society is offering $1 million in backstop grants—but it’s likely not enough
https://www.scientificamerican.com/article/can-u-s-math-research-survive-nsf-funding-cuts/
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Annette Dittert
7 months ago
At last. This really is excellent news! Something the EU had asked for a very long time ago. Looks like Yvette Cooper now lost that battle to limit it to 12 months. Good. It's high time young Brits and Europeans can get to know each other again.
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Young Europeans may be allowed to stay in UK for longer than a year
A minister has opened the door for a reciprocal youth mobility scheme that could add to net migration figures despite concerns from the Home Office
https://www.thetimes.com/uk/politics/article/eu-youth-mobility-scheme-uk-7spbxfth0
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Good Law Project
7 months ago
TalkTV spreads hate and transphobia as if there was no consequences. Let's prove them wrong. Join over 10,000 people - send your complaint to Ofcom 👇
action.goodlawproject.org/ofcom-stop-t...
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Ofcom: stop TalkTV broadcasting hate
TalkTV is Rupert Murdoch’s Fox News for the UK – a constant source of toxic hate and far-right lies. Over the last 11 weeks, TalkTV has been spouting transphobic hate again and again – totally ignorin...
https://action.goodlawproject.org/ofcom-stop-talktv?utm_source=Bluesky&utm_campaign=OfcomComplaintTalkTV&utm_medium=Social
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I am visiting Belfast for a conference on topological groupoids and C*-algebras (
www.newton.ac.uk/event/tgaw02/
). Belfast is pretty in the summer!
7 months ago
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I am rewatching
#StarTrek
#DS9
at the moment and the episode "Past Tense" still hits very close to home. I remember that I thought "Nah, it's not going to be like that in 2024". Oh boy, was I wrong.
7 months ago
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Bookshop.org
7 months ago
You are cordially invited to our Anti-Prime Sale, where every purchase will financially support bookstores, NOT billionaires 🥳
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Petra Schwer
8 months ago
Kleine Erinnerung: Heute 17 Uhr in Heidelberg
add a skeleton here at some point
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David Jekel
8 months ago
New math paper with Yoonkyeong Lee, Brent Nelson, and Jennifer Pi.
arxiv.org/abs/2506.19940
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Strong convergence to operator-valued semicirculars
We establish a framework for weak and strong convergence of matrix models to operator-valued semicircular systems parametrized by operator-valued covariance matrices $η= (η_{i,j})_{i,j \in I}$. Non-co...
https://arxiv.org/abs/2506.19940
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Margot Finn
8 months ago
Really quite an excoriating indictment of university governance, this. Desperately needs to be confronted by the sector as a whole rather than swept aside as an anomaly. This is not an edge case. Live reporting from the BBC:
www.bbc.co.uk/news/live/c1...
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Former Dundee University principal accused of being a coward
Prof Iain Gillespie, former principal and vice-chancellor of the University of Dundee, is grilled by members of Holyrood's Education Committee.
https://www.bbc.co.uk/news/live/c15wqn0zxx7t
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NationCymru
8 months ago
Vice Chancellor Larner wants Cardiff University to be a ‘living experiment’, as a ‘part social innovation lab, part corporate partnership innovation centre, part civic system transition space’ with constant ‘creative destruction and continual regeneration’
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Lecturers from Cardiff University predict its dystopian future
Anonymous What will a “leaner and more efficient” Cardiff University look like? Cardiff University’s Executive Board has set out their vision for ‘digital transformation’ in Wales in 2035, where ‘digi...
https://wp.me/p8Mk4U-11wm
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