This is very nice recognition of Hal Gabow! Hal spent his whole career as faculty at CU Boulder, and his legacy looms large for us. (Hal retired in 2008, and I unfortunately have never gotten a chance to meet him.)

His papers are where I learn from the most lately.
I would love to meet him once in my life too.

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

Topics researchers might find worth browsing:
🔹 A unified treatment of variants of expander decomposition and expander hierarchies
🔹 Cut-matching games under updates
🔹 A unified view of dynamic shortest paths and push-relabel
🔹 Combinatorial max flow via directed expander hierarchy

I poured my soul into building this course last fall:

📚 Graph Algorithms via Graph Decomposition 📚

Graph decomposition has been a powerful framework in graph algorithms for over 20 years, but the literature is scattered and technical.

Thus, I tried to organize part of it into one coherent story.

1/3 Fine-Grained Complexity Fest at DIMACS this July! Three back-to-back workshops on Algebraic Techniques, String Algorithms, and Graph Algorithms in fine-grained complexity, with a terrific speaker lineup. Organized by
@jalman.bsky.social , Elazar Goldenberg, and
@eigx.bsky.social.

New SIGACT award expository work, created in memory of Luca Trevisan: "intended to promote and recognize high-impact work expositing ideas and results from the Theory of Computation."

A wonderful initiative—consider nominating people!

⏰ Nomination deadline: April 10
sigact.org/prizes/trevi...

Stanford AI Club: AI and the Future of Education YouTube video by Stanford AI Club

Given AIs, I am still not sure how to teach algorithm classes today and in the future.

This discussion is quite nice, though.
www.youtube.com/watch?v=Vnz8...

It's first round interview season and the most useful thing I can recommend is to spend time on these: csfaculty.github.io

#FOCS2025
This is one of the best FOCS conferences I have attended.

Frontiers of Graph Algorithms | Day 1 | 8th Dec 2025 YouTube video by CSAChannel IISc

I just gave a tutorial on Design Templates for Dynamic Graph Algorithms at IISc in Bangalore.

The kindest words I received were "best tutorial I have listened to in the last 10 years." Hope it interests you.

Video: www.youtube.com/live/L8ev24g...
Slides: tinyurl.com/yetx3vxu

The 2025 Chicago Junior Theorists Workshop is December 8-9, hosted jointly by Northwestern and TTIC. Monday Dec 8 will be at TTIC and Tuesday Dec 9 will be at Northwestern (in the SkAI/NITMB in the Hancock tower in downtown Chicago). Register in advance.

theory.cs.northwestern.edu/2025/11/14/j...

A New Bridge Links the Strange Math of Infinity to Computer Science | Quanta Magazine Descriptive set theorists study the niche mathematics of infinity. Now, they’ve shown that their problems can be rewritten in the concrete language of algorithms.

The connection between distributed algorithms and descriptive set theory featured in Quanta:
www.quantamagazine.org/a-new-bridge...

I used AI to create an easier-to-navigate schedule for SODA and SOSA 26 here:
soda26.netlify.app

The original one is hard to see the overview. meetings.siam.org/program.cfm?...

What Is Understanding? – Geoffrey Hinton | IASEAI 2025 YouTube video by International Association for Safe & Ethical AI

This talk is really illuminating to me (especially around minute 7 to 11).

Clearly, I intuitively know what understanding is, but his explanation makes it much more explicit and makes sense.

youtu.be/6fvXWG9Auyg?...

Announcing the 7th Learning Theory Alliance mentoring workshop on November 20. Fully free & virtual!

Theme: Harnessing AI for Research, Learning, and Communicating

Ft @aaroth.bsky.social @andrejristeski.bsky.social @profericwong.bsky.social @ktalwar.bsky.social &more

Congratulations to Venkat Guruswami, new director of the Simons Institute for the Theory of Computing (@simonsinstitute.bsky.social)! And congrats to us, the Theoretical CS community, for having someone as good, dedicated, and wonderful as him at the helm of a place so important to us! #TCSSky

Nominate your final-year TCS PhD students or postdoc for the 2025 Chicago Junior Theorists Workshop (hosted by Northwestern and TTIC).

theory.cs.northwestern.edu/2025/10/30/2...

I hope this is a good step towards "clarity", an essential goal in science.

This is a joint work with the fantastic team: Aaron Bernstein, Joakim Blikstad, Jason Li, and Ta-Wei Tu.

Joakim and Ta-wei coded up the algorithm.
3/3

Combinatorial Maximum Flow via Weighted Push-Relabel on Shortcut Graphs We give a combinatorial algorithm for computing exact maximum flows in directed graphs with $n$ vertices and edge capacities from $\{1,\dots,U\}$ in $\tilde{O}(n^{2}\log U)$ time, which is near-optima...

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

Maximum Flow by Augmenting Paths in $n^{2+o(1)}$ Time We present a combinatorial algorithm for computing exact maximum flows in directed graphs with $n$ vertices and edge capacities from $\{1,\dots,U\}$ in $n^{2+o(1)}\log U$ time, which is almost optimal...

Can a max flow algorithm be both near-optimal and simple enough to teach?

Last year, we showed that the classical and intuitive augmenting-path approach can indeed be almost optimal for dense graphs.
arxiv.org/abs/2406.03648

But the result was not actually satisfying!
1/3

TCS+ RSVP: Ian Mertz (2025/22/08) Title: A Random Walk Down Full Memory Lane

📢 Our second TCS+ talk of the season will be Wednesday, Oct 22 (10amPT, 1pm ET, 19:00 CEST): Ian Mertz, from Charles University, will give guide us through "A Random Walk Down Full Memory Lane"!

RSVP to receive the link (available one day prior to the talk): forms.gle/495UjiLmQkkD...

Interview with Steven Strogatz YouTube video by Math-life balance

It was such a pleasure being a guest on "Math-Life Balance", a podcast devoted to interviews with mathematicians. Mura Yakerson is a fantastic interviewer! Check out our chat at www.youtube.com/watch?v=Gx8F... #mathsky

New Method Is the Fastest Way To Find the Best Routes | Quanta Magazine A canonical problem in computer science is to find the shortest route to every point in a network. A new approach beats the classic algorithm taught in textbooks.

This is very impressive. Breaking the sorting barrier for directed single source shortest paths
search.app/wnEUo

Lecture 4.1: Amortized Analysis: Bank account method, Binomial heaps, Hollow heaps YouTube video by Thatchaphol Saranurak

This lecture provides a gentle introduction to amortized analysis.

For experts: At the end, I explained Hollow Heaps, an optimal heap like Fibonacci heaps, but simpler! Surprisingly, I have not seen video lectures on this before.

www.youtube.com/watch?v=8mHa...

Lecture 0: Introduction YouTube video by Thatchaphol Saranurak

Math vs. Cooking:
What does it mean to do math/theory?

Here, I presented an analogy to cooking.
The goal was to help students understand how to effectively learn in theory classes.

www.youtube.com/watch?v=8Fz2...
(The discussion at 59:38)

I am curious to know if you think this makes sense.

The list of accepted papers at #FOCS2025 is up!

focs.computer.org/2025/accepte...

LEADERSHIP LAB: The Craft of Writing Effectively YouTube video by UChicago Social Sciences

Wow, this might be the best lecture on academic writing I've ever watched!
www.youtube.com/watch?v=vtIz...

If any of you have suggestions for good materials related to grant writing and/or mathematical writing, I would be interested :)

Professor Sepehr Assadi stands by a bench in Waterloo's Peter Russell Rock Garden.

Professor Sepehr Assadi has won the 2025 Presburger Award, a prestigious honour recognizing his exceptional contributions to theoretical computer science, in particular his pioneering work on establishing lower bounds for multi-pass streaming algorithms.

cs.uwaterloo.ca/news/sepehr-...

Omg