"I haven't really seen further than others, but they were looking in another direction." Academic tip: we're not all Newtons, and that's completely OK! You don't need to be a genius to do good research.

A few weeks ago I gave a talk at the New York Geometry Seminar about the alpha-Ham-Sandwich theorem. The talk is now online on YouTube: m.youtube.com/watch?v=MEiq...

If you want to know a bit more about my recent paper with Juan, Ernst and Bastian, watch this video of Juan explaining it :)

A new paper on the #arXiv: with Daniel, Henry, Fabian, Irene and Birgit we study piercing double wedges (which in the primal corresponds to finding lines intersecting some segments and avoiding some others). We give algorithms but also Gallai-type combinatorial results. arxiv.org/abs/2604.23330

Prof. Susanna Zimmermann has been invited to speak at the International Congress of Mathematicians — a major honour. First woman from the University of Basel. A specialist in algebraic geometry. dmi.unibas.ch/en/news-even... #ICM2026 #Mathematics #UniBasel

A new paper of mine finally on the arXiv :)

A special treat for the students in my course „Introduction to Topological Data Analysis“: Bastian Rieck (@pseudomanifold.topology.rocks) gave a very interesting guest lecture on topological methods in deep learning.

Very nice explanation of one of my favorite theorems in math, the Ham Sandwich theorem, by @manonym025.bsky.social www.scientificamerican.com/article/the-...

🔗 Full materials: sites.google.com/site/thsaran...

Day 3 of #EuroCG26 started with an invited talk by Jean Cardinal on compact representations of graphs, where he particularly focused on biclique covers. An interesting topic I did not know about before.

Highlights from day 2 of #EuroCG26. The day started again with an invited talk, today by Maike Buchin who took us on a tour of 35 years of Frechét distance. A very interesting talk, and lots of great illustrations of dogs on walks.

Some personal highlights from day 1 of #EuroCG26: the day started with a great invited talk by Marcus Schaefer about penny graphs and the existential theory of the reals. I recently worked quite a bit in ETR, and it was very interesting to hear one of the founding fathers.

I am at #EuroCG26 in Hagen this week. It is once again an amazing conference with lots of interesting talks and discussions. There are also some of my MSc students from ETH here, attending their first ever conference, and it‘s great to see how they are welcomed by the CG community.

Very cool question with an elegant solution that I also discussed last week in my lecture (I‘m not going to say which lecture so as not to give hints about the answer) ☺️

Spending an interesting week at Schloss Dagstuhl at the workshop „Intractability in Discrete Geometry and Topology“. A very nice venue, some cool open problems, and even cooler participants. www.dagstuhl.de/seminars/sem...

Last semester, I organised „Projects in Topological Data Analysis“, where students from several universities collaborate on problems in TDA. My Students Jette and Kalani, together with their mentors Anna and Tim have just uploaded their findings from their project to ArXiv: arxiv.org/abs/2603.07809

📚 New in arXiv cs.CG: Garment numbers of bi-colored point sets in the plane

A new paper on the ArXiv. This one is a result of the research week on geometric graphs in Trier in August 2024. Together with my coauthors Oswin, Helena, Niko, Maarten and Pepa we study a variant of the empty monochromatic quadrilateral problem. arxiv.org/abs/2603.05339 This will be at #EuroCG26

Really cool result by Joseph Dorfer

The list of accepted papers at #SoCG26 is now online: cgweek26.computational-geometry.org/contribute/

The list of accepted papers at #EuroCG26 is online: eurocg26.fernuni-hagen.de/accepted-con...

For those on hiring committees: do you push back against this? What do you do?

The city of Basel is getting ready for its three most beautiful day. I have a very privileged view of this from my office.

For my randomized algorithms course at the University of Basel, the students will have to present some randomized algorithms to their peers. If you know any algorithm that you think would be particularly interesting, let me know and I‘ll add it to the list of suggestions :)

Today I also started my semester in Basel, where I‘m teaching two courses at @dmi.unibas.ch : a BSc course on algorithms and data structures and an MSc course on randomized algorithms.

I just finished the first lecture of my course „Intro to TDA“ at ETH. It‘s great to see interest steadily increasing, this year there are almost 90 people registered. If you want to know more about what we‘re doing, we have a lecture page with some public material: ti.inf.ethz.ch/ew/courses/T...

IPE is amazing, looking forward to try out this new feature!

The list of accepted papers at #STOC2026 is out: acm-stoc.org/stoc2026/acc... Congratulations to all authors!

📚 New in arXiv cs.CG: Splitting Sandwiches Unevenly via Unique Sink Orientations and Rainbow Arrangements

A new paper on the #arXiv. Together with Michaela, Sebastian, Hung and Simon we revisit the alpha-Ham-Sandwich theorem. This paper was also accepted at #SoCG26. arxiv.org/abs/2602.10795

On today‘s menu: supervising a 5 hour programming exam.

The notifications for #SoCG26 are out. 95 out of 272 submissions got accepted. Looks like I have provided both an accepted as well as some rejected submissions.

Great news for the CG community: #SoCG is now ranked as an A* conference in the newest CORE rankings! portal.core.edu.au/conf-ranks/?... I personally think that rankings should be taken with a grain (rather a rock) of salt, but it’s still nice that the great work of the conference is recognized.

Very proud of my student Juan Amboage, who managed to get his Master thesis accepted at #ICLR2026, with significant help by Ernst Röell and @pseudomanifold.topology.rocks , and very very little input from my side. If you want to know more, here is the ArXiv version: arxiv.org/abs/2510.00757

The number of people arguing, following the #NeurIPS2025 case, that a bit of systematically bad scholarship and borderline academic misconduct is OK because doing things the right way is tedious and time-consuming is concerning. Yes, doing things well might be boring. But doing them badly is... bad

I just supervised my 8th large bring your own device programming exam, but it was the first one where a students laptop started updating windows in the middle of the exam.

If you know people in Theoretical CS or adjacent who just joined BlueSky (or just did yourself), please tag them or say hi in this thread! #TCSSky (I'll follow them/you, let's strengthen our research community here)

The odd Hadwiger conjecture has been disproved by Marcus Kühn, Lisa Sauermann, Raphael Steiner and Yuval Wigderson. arxiv.org/abs/2512.20392

Published today 18Dec2025: *The Mathematics of Origami.* Cambridge link: view.updates.cambridge.org?qs=99a0b7610... #MathSky #MathArt #Mathematics #Geometry #Science #Origami

Something non-academic for once: getting ready for a concert with the student orchestra Polyphonia

A special treat for my Software Engineering Students at @dmi.unibas.ch: today Michela Schorta and Dominik Berger (organizers of @baselone.bsky.social) gava a guest lecture about agile software development.

The application deadline for the ETH Student Summer Research Fellowship is in a week. This fellowship is an amazing opportunity to do research in Zürich for a summer. inf.ethz.ch/studies/summ...

The pre-recorded videos (for the talks whose authors opted in to submit one) are now available on our YouTube channel: m.youtube.com/@FOCS2025 They're also linked from the main website's schedule!

I‘m in the program committee of #EuroCG26, which takes place March 25-27 2026 in Hagen. Please send us some interesting papers to read :) eurocg26.fernuni-hagen.de/index.html

During the semester, the students of my software engineering course at @dmi.unibas.ch created extensions to the open source citation manager JabRef. Today we had the final presentations. I was impressed by their creativity, I saw some really cool features like gamifications and citation graphs.

I can highly recommend working here :)

Looks like I‘ll have some nice literature for the christmas break :)

Both low-level implementation and analysis were previously very involved. But our new paper simplifies both significantly. Now - Pretty readable for non-experts. - Simple enough to code up fully in C++ - I am trying to teach it this semester arxiv.org/abs/2510.17182 2/3

Accepted papers for SOSA 2026, congrats to Sebastian Haslebacher and Jonas Lill of our group on their accepted paper on finding Tarski fixpoints. www.siam.org/conferences-...

The journal paper for the topology-based clusterer AuToMATo that I developed with Marius Huber and Sara Kalisnik is now online: openreview.net/pdf?id=Qd7H5... The code of AuToMATo is public: github.com/m-a-huber/au... Feel free to use it, especially in combination with the Mapper algorithm :)