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cgrefe.bsky.social
Christian Grefe
@cgrefe.bsky.social
580 followers 310 following 690 posts
Particle physicist at University of Bonn, working on the ATLAS experiment at CERN. https://orcid.org/0000-0001-7050-5301
orcid.org
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · Nov 12
I guess it is time for a re- #introduction: I am a researcher at the University of Bonn and work on the @atlasexperiment.bsky.social at CERN. I post mostly about particle #physics, academia in Germany ( #IchBinHanna), and life in Geneva. 🧪⚛️
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 2d
Putting company data on a shared Google sheet is not better.
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Christian Grefe @cgrefe.bsky.social · 2d
Would be nice if it had exactly one page which says: "Just don't. Please get actual care."
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 2d
Das alte Testament.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 3d
Sure.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 3d
This is for people who have other income that supports you getting a PhD. If you work in industry or at a research lab for example. I was paid by CERN during my PhD, but got my degree from a university. I also know cases where retired people did a PhD without additional pay.
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 3d
You don't need a PhD contract to do a PhD. In most cases you can just write a thesis and hand it in. *Details depend on the Promotionsordnung.
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Christian Grefe @cgrefe.bsky.social · 3d
Da ist man zwei Wochen nicht in Genf in dann so etwas...
Oktoberfestzelt in Genf.
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Christian Grefe @cgrefe.bsky.social · 4d
In German we have "Montagswagen", same concept but referring to Monday. The idea is that on Mondays people still have to find back their routine after the weekend and will thus produce more faulty products.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
The Briefing Book for the Update of the European Strategy for Particle #Physics is out! It is a summary of the state and the ambitions of the field, summarising the hundreds of community and national white papers we received as input earlier this year. ⚛️🧪 cds.cern.ch/record/2944678
Physics Briefing Book: Input for the 2026 update of the European Strategy for Particle Physics
The European Strategy for Particle Physics (ESPP) reflects the vision and presents concrete plans of the European particle physics community for advancing human knowledge in fundamental physics. The E...
cds.cern.ch
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Reposted by Christian Grefe
dangaristo.bsky.social
Dan Garisto @dangaristo.bsky.social · 7d
Had never read Jane Goodall's original 1963 article in Nat Geo on the wild chimpanzees in Tanzania until now. It's a wonderful blend of science and journalism, and well worth your time.

www.nationalgeographic.com/pdf/jane-goo...
David Greybeard, a wild chimpanzee, gets a handout of bananas from author Goodall, who studies the apes under a National Geographic Society grant. This scene near her camp represents a triumph for Miss Goodall; at first the animals fled if she came within 500 yards. Knapsack holds camera and notebook. She carries a whistle in her pocket to summon searchers in case of accident in the rugged Tanganyika hills.
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
Auch in der Politik gibt es das nur für die erste Reihe.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
Worth following @acollierastro.bsky.social
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
Here is an entertaining take on all of those anti-science grifters on YouTube and elsewhere. Highly recommended. youtu.be/miJbW3i9qQc?...
conspiracy physics and you (and also me)
YouTube video by Angela Collier
youtu.be
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Christian Grefe @cgrefe.bsky.social · 7d
⚛️ 🧪
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
The physics institute of the @unibonn.bsky.social hosted the US team of this year's Beamline4Schools at our own electron accelerator ELSA. They measured transition radiation photons using various targets, and I had the pleasure to meet them and chat about physics. What a bunch of smart kids!
cern.bsky.social
CERN @cern.bsky.social · 7d
It’s a wrap for #BL4S 2025 💫

From 10 to 24 September, CERN, DESY and the University of Bonn welcomed the winners of the 2025 Beamline for Schools (BL4S) competition.

Find out more: home.cern/news/news/ce...
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 7d
"Wirtschaftskompetenz"
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Christian Grefe @cgrefe.bsky.social · 8d
Ähnlich übrigens in der Schweiz, das eigentlich nur zwei Hauptachsen hat, und darüber hinaus viel kürzere Strecken hat.
IC Netzkarte in der Schweiz.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 8d
Natürlich macht Japan einen besseren Job bei der Bahninfrastruktur, trotzdem kann man die Komplexität der beiden Schienennetze einfach nicht vergleichen. Die größten Verspätungen hat man in Deutschland wenn man einen Anschluss verpasst. Japan hat nur eine lange Linie mit ein paar Abzweigungen.
Karte des Shinkansen-Netzes in Japan.
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Christian Grefe @cgrefe.bsky.social · 8d
That's an Opel Rocks-e (identical to the Citroen Ami). You can drive it already at the age of 15 because its top speed is only 45km/h. This is probably the most German way to park it - blocking the whole sidewalk despite its small size... www.opel.de/fahrzeuge/ro...
Neuer Opel Rocks | Elektro Kleinwagen | Opel DE
Hol dir den Opel Rocks – dein kleines Elektroauto für die Stadt! Kompakt, erschwinglich und stylischem Platz für zwei Personen. Entdecke ihn jetzt!
www.opel.de
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Reposted by Christian Grefe
quaxquax.bsky.social
Henning Dekant 📎 @quaxquax.bsky.social · 10d
Difficult for me to put into words how disappointed I am in Sabine Hossenfelder. Many years back when she was just blogging about physics I was a huge fan, and she published a lot of intriguing papers. Now she makes money as a social media arsonist. 🧪
www.mcgill.ca/oss/article/...
Sabine Hossenfelder Asks If Science Is Dying. It’s Not.
Physics is dying. It’s mathematical fiction. Science is failing. Most of academic research that your taxes pay for is almost certainly bullshit. I don’t trust scientists. Would you believe me if I tol...
www.mcgill.ca
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 9d
The ICE 3neo has a top speed of 200 mph, but only when operating in France 😉 Most of the German railway network is not certified for the highest speeds, so the newest flavour ICE L, which will go into operation soon, has a top speed of only 150mph.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 9d
Die Englischkenntnisse in der Breite der Bevölkerung dürften immer noch schlecht genug sein, dass sich das nicht negativ auf die Verkaufszahlen auswirkt. Gerade in der Zielgruppe. Alle anderen verdrehen die Augen.
cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 9d
Erklärt tatsächlich einiges
Reposted by Christian Grefe
danabra.mov
dan @danabra.mov · 12d
i wrote about atproto and why it matters
Open Social — overreacted
The protocol is the API.
overreacted.io
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cgrefe.bsky.social
Christian Grefe @cgrefe.bsky.social · 10d
About time
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