Interested in everything. I tweet here primarily about science when I have time and something non-trivial to say.

Joined June 2010
102 Photos and videos
Bravo to @stevenstrogatz for attempting the impossible task of presenting the renormalization group method for singular perturbation problems in one lecture! Here's a short thread that he inspired me to write while taking a break from final exam grading & COVID-19 work for UIUC.
5
39
203
Here's a thread about renormalization group and asymptotics. It's at the other place, which is nicer than here. I've never been trolled there. Maybe it's because there's nobody there 😞. bsky.app/profile/nigelgolden… It's about this new paper arxiv.org/abs/2406.18784

3
3
14
1,250
@stevenstrogatz might be interesting to you for when you next teach asymptotics and perturbation theory. The thread is over at Bluesky but refers to the thread I posted a few years ago on Twitter about RG, after the video from your course on RG.
4
617
New paper showing that the laminar-turbulent transition in pipe flow is in the directed percolation universality class. We finessed the need for a 4km long pipe and 100 years of data using RG, molecular dynamics, and fine data on puff interactions. nature.com/articles/s41567-0…
13
47
6,389
Hi, I've joined bluesky, and if I have time to read and post on social media, I'll be doing it on that platform in the future.
3
735
Nigel Goldenfeld. @NigelGoldenfeld.bsky.social retweeted
22 Sep 2023
Postdocs! Please apply to join our lab and work on mathematical/computational projects in cancer evolution and screening. Happy to discuss any details and tell you all about us 🤓 Please RT #mathonco
31
53
12,356
Great choice! For a detailed account of the significance of this paper, please see my article with Norm Pace and Jan Sapp pnas.org/doi/10.1073/pnas.11…
Day 29/30 of great biology papers. "Phylogenetic structure of the prokaryotic domain: The primary kingdoms," by Carl Woese & George Fox (1977). Perhaps the most important paper in evolutionary biology. It established a "third domain" of life. *** This paper is just 2.5 pages in length. It contains a single table as its figure. Its publication went largely unnoticed by biologists, but The New York Times printed a story about a "third type of life" on its front page. Prior to this study, all life was divided into two categories: Cells that have a nuclear membrane (eukaryotes), and cells that don't (prokaryotes). Francis Crick first proposed "comparing sequences to infer relationships" as early as 1958. But this paper heralded the dawn of molecular phylogenetics. Woese and Fox claimed, provocatively, that "all cellular life falls into one of three large relatedness groups: eukaryotes...eubacteria, and archaebacteria." (See pnas.org/doi/epdf/10.1073/pn…) They made this claim by sequencing a single, highly-conserved gene across many organisms: Ribosomal RNA. This is the catalytic part of ribosomes, the protein-making machines inside of cells. By studying how rRNAs had mutated over eons and eons, Woese and Fox inferred the evolutionary connections between cells. Many well-regarded microbiologists at the time believed that the relationships between microbes could not be determined without a fossil record. This sounds hilarious in hindsight. But it was a real, mainstream belief. Roger Stanier, who helped modernize microbiology and was a respected professor at UC Berkeley and the Pasteur Institute, wrote in his textbook, The Microbial World, in 1970: "[r]eflection and experience have shown, however, that the goal of a phylogenetic classification can seldom be realized. The course that evolution has actually followed can be ascertained only from direct historical evidence contained in the fossil record. This record is at best fragmentary and becomes almost completely illegible in Precambrian rocks more than 400 million years old." Overturning dogma and telling professors that they're wrong is fun! A classic. One more day to go! Paper: pnas.org/doi/full/10.1073/pn…
5
23
6,145
theguardian.com/science/2023… Fondly remembering John Harries. He gave me my start as a professional scientist. I worked with him in my gap year before university, at National Physical Laboratory. My job was to compute infra-red absorption by the upper atmosphere.
1
13
2,389
... the basic equations describing the experimental setup of the apparatus, saw how basic physics could be turned into a predictive engineering design tool. I'd never seen anything like that before and it opened my eyes to how science is done. John was very kind & encouraging ..
1
4
958
... to a naive and ignorant but enthusiastic kid. My first paper was an NPL internal report "Theoretical study of some properties of the selective interferometer filter". Thank you, John. Never forgot you over the intervening years.
3
857
Good opportunity for anyone interested in microbial population dynamics and ecology to work at the interface of ML and theory with extensive and unique datasets!
There is a new postdoctoral opportunity to work with us at UCSD on AI/ML approaches. I would be keen to hear from anyone interested in this to work with us on microbiome-focused studies, particularly around time series analysis. postdoc.ucsd.edu/funding/sch…
3
4
Nigel Goldenfeld. @NigelGoldenfeld.bsky.social retweeted
Astrobiologists are thrilled after discovering a location on Earth that’s excellent for answering questions about the exploration of Saturn’s moon Enceladus & similar hydrothermal systems on other ocean worlds. Here’s what makes the analog site so unique: go.nasa.gov/3Emckns
24
342
3,013
Nigel Goldenfeld. @NigelGoldenfeld.bsky.social retweeted
Congratulations🎉 to @UCSDPhysics Professor Olga Dudko on being named an American Physical Society Fellow for her outstanding work in theoretical physics. bit.ly/3eTV2FA @APSphysics
3
9
49
Nigel Goldenfeld. @NigelGoldenfeld.bsky.social retweeted
More positions announced at @CDCgov Center for Forecasting and Outbreak Analytics: Data Scientists (including disease modelers) level GS-12 usajobs.gov/GetJob/ViewDetai…. . Apply to join a growing team to develop the best forecasting and analytics to improve decision making!

5
101
149
One of my students did this & it literally changed his life. Interested in science for society & this Fellowship opened doors. Made an impact on Capitol Hill and beyond. Now a very senior person in the national scientific infrastructure. Great chance to make a difference 👇👇👇
Looking to take your scientific expertise to Capitol Hill? Apply for the APS Congressional Science Fellowship to work alongside Members of Congress on their staff and help develop evidence-based decisions regarding public policy. Submit an app by Dec. 1! go.aps.org/3wKwFju
7
12
Nigel Goldenfeld. @NigelGoldenfeld.bsky.social retweeted
Why do biological limbless crawlers execute extension-contraction waves? Traveling waves of muscle contraction are the most energy-efficient: they maximize the body’s displacement with minimal energy consumption. Great work @SreejithS_!👉journals.aps.org/pre/abstrac…
2
16
56
Sad to see my former institution @UofIllinois no longer following the science to protect its students, faculty, staff & surrounding community. SHIELD gone. Vaccination required, not boosters. No masking. No surveillance/entry testing. Full classrooms. massmail.illinois.edu/massma…
11
19
58
See time series of cases and positivity above. Daily test positivity is 20% today, up from 15% yesterday. Hard to interpret due to multiple biases, but it means there is chronic under-testing, with no information about prevalence other than that it is not low.
2
2
11
These data are from the university's dashboard go.illinois.edu/COVIDTesting…

The comparison between Aug 2020 and Aug 2022 is a grim A/B test or control that I hoped never to see. Covid is not behind us. I hope @UofIllinois re-engages with its brilliant & dedicated scientists/public health professionals to create a safer environment for its community.
1
12