Sign in

Predrag Cvitanović

@chaosbook.bsky.social
739 followers 1.8K following 173 posts

Theoretical physicist. Publications and online courses on field theory, group theory, chaos, turbulence - ChaosBook.org/~predrag. Please list your online talks on researchseminars.org, blueprint them here.

PostsRepliesMedia
Reposted by Predrag Cvitanović
Scott Horton @robertscotthorton.bsky.social · 5h
Princeton, McGill and Penn have all denied tenure to women who went on to win a Nobel Prize. It says quite a bit about tenure standards, and the treatment of women in academia. MAGA thinks that DEI gives them an unfair advantage. And that's farcical. www.forbes.com/sites/conorm...
forbes.com
Researcher Demoted By University Of Pennsylvania Wins Nobel Prize For mRNA Discoveries—And Some Academics Urge Penn To Apologize
Katalin Karikó’s research laid the foundation for both the Pfizer/BioNTech and Moderna Covid-19 vaccines.
7302147
Reposted by Predrag Cvitanović
Will Thomas @williamthomas.bsky.social · 09/10/2026
In today's AIP History Weekly Edition, we look at the first Nobel Prize in Physics in 34 years to be awarded to a single person. Halzen is a peculiar choice for a solo prize, given IceCube's multifaceted collaborative structure and Halzen's own view that his leadership role was almost accidental.
aip.org
Francis Halzen and the anatomy of a solo Nobel Prize
AIP History Weekly Edition: October 9, 2026
083
Reposted by Predrag Cvitanović
Phil PlAIt @philplait.bsky.social · 08/10/2026
An absolute giant.
6745139
Predrag Cvitanović @chaosbook.bsky.social · 08/10/2026
Do read this - chatbots are trouble in STEM writing, but they are utter disaster in general publishing...
010
Reposted by Predrag Cvitanović
Will Ratcliff @wcratcliff.bsky.social · 07/10/2026
Out today in @nature.com: our review on how single cells evolve into multicellular organisms. With Ozan Bozdag, @kaitong25.bsky.social, Peter Yunker, and @matthewherron.bsky.social. rdcu.be/9ZuiKow9twKa For an overview, check out the video below.
11349152
Reposted by Predrag Cvitanović
Joshua Weitz @joshuasweitz.bsky.social · 08/10/2026
Just another normal day for an admin that proposed to slash NSF's FY27 budget in half & diverted more than $1.4B in research funds last year and is now hosting a New Golden Age of Science Summit at the Donald J. Trump Institute for Peace (formerly, the United States Institute for Peace).
White House OSTP 47 Live Science: A New Golden Age Summit at the Donald J. Trump Institute of Peace
1125
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 08/10/2026
Astronomers have discovered the fastest-known star in the Milky Way zooming around Sagittarius A* in an extremely close orbit. Observations of this star, known as S301, could shed new light on the spin of the supermassive black hole at the centre of our galaxy. 🧪⚛️ physicsworld.com/a/fastest-st...
physicsworld.com
Fastest star in the Milky Way feels the rotation of our central black hole – Physics World
The Milky Way’s massive black hole is rapidly rotating, and a star in an unprecedentedly close orbit could help measure its spin
3265
Reposted by Predrag Cvitanović
Rodger Sherman @rodger.bsky.social · 07/10/2026
John Urschel has his CV on his MIT professor page and if you scroll past 7 pages of his mathematics achievements and awards and theorems and theses it says, briefly, "former NFL (American) football player" math.mit.edu/~urschel/job...
math.mit.edu
2646472
Reposted by Predrag Cvitanović
Philip Ball @philipcball.bsky.social · 07/10/2026
"The Man Who Broke Reality is comprehensive, authoritative and shrewd, and, like all of Philip Ball’s books, as entertaining as it is enlightening." I could not be more pleased with this review from the legendary John Banville. www.ft.com/content/e8a1...
ft.com
The Man Who Broke Reality: Niels Bohr and the Making of Modern Physics
Philip Ball’s entertaining biography is a guide to both the life of the Danish physicist and the mind-boggling quantum science that he, alongside Einstein, did much to advance
1206
Reposted by Predrag Cvitanović
crumb @crumb.bsky.social · 07/10/2026
news.ycombinator.com/item?id=4998...
ihoggan 
 I was a graph theory junkie long ago and even moved to Budapest for awhile to study among the greats. While I was there I started working on Barnette's Conjecture which came to occupy my thoughts over the next 24 years of my life, on and off as I worked in many different fields. Last summer I even thought for a few days that I had actually solved it. But it's supposedly proven here - problem 180. I don't know what to think exactly. I spent thousands of hours on that problem. I really enjoyed it. Hearing that it is solved somehow makes me sad in a far-off way, like hearing an ex-girlfriend died suddenly in a car crash. I don't know, there's probably a lot of people feeling odd emotions tonight. There's no Lean proof for this one so I'm digesting the paper. On the surface it looks like an approach I considered 24 years ago and abandoned. 
I revisited the problem this summer, along with my partial solutions, when the previous round of stunning proofs came out. Several hours of work with Fable simply convinced me it wasn't yet solvable and reinforced how hard of a problem it was. 
 WheelsAtLarge
I have very little understanding of higher math, so I ask you: Was the proof due to a type of brute-force solution that could be solved had you gained enough information from reading others' work, or was it more like a proof that was sparked by an insight that came once a clue on how to solve it was put forward? I guess my question is: Was the problem proven by using a collection of everyone's work, or was it due to a brand-new insight? 
reply 
jboggan
 Hi I'm still digesting the proof and translating a bit from the dual case back to the primal in which I most commonly thought about it. I don't think it was a brute force proof in the sense that it combined every possible paper and commentary. It's rather odd because I feel like most of the work on the conjecture was focused on an induction proof based around graph reductions, and this proof avoided those issues entirely by offering a concrete constructive proof of finding a Hamiltonian cycle. Rather, it explicitly selected the edges not in the Hamiltonian cycle, which is in line with previous attempts via the dual. 
The "oho" insight for this is actually f**ing wild, it involves a complex valued exponential sum on the edges. I've seen a lot of clever counting arguments before in graph theory but this is the first time I've seen complex roots and annihilating terms like this, the symbolic manipulation tricks in this look like things out of quantum physics. I don't understand where this trick originated, I need to really digest this. 



jboggan
 I went back to that Fable chat and showed it this new preprint. It coded up the new constructive algorithm and ran it against the existing test suite, that looks good at least. 
It has been super helpful in delineating where the crucial concept came from. The proof is rather simple as graph theory proofs go, but it does seem to use some constructions that would only seem obvious if you had serious physics experience with partition function and calculating energy states that cancel out. It's not a wholly alien bolt from the heavens, but I can also see how there hasn't been a human being with the broad theoretical physics knowledge combined with the deep graph theory experience in planar graphs to come up with this idea. I don't know, I'm looking for precedents of this formulation and some old papers of Penrose counting the number of edge colorings of this same graph type are coming up, the line of argument at least rhymes. But I agree with the thought that this sort of progress should not be siloed inside those companies. I propose a tax so that every slop cannon Al video pays for another hour of compute time for advancing mathematics. 
reply
823452
Reposted by Predrag Cvitanović
Joshua Weitz @joshuasweitz.bsky.social · 07/10/2026
Supplementary Information is finally being taken seriously! (oh wait... oh no...) www.nih.gov/news-events/...
nih.gov
NIH joins effort to build SI-ready data for predictive models of human biology
NIH-led Bio Genesis Mission will leverage existing biomedical data resources to accelerate SI-enabled discovery and improve human health.
2163
Reposted by Predrag Cvitanović
Yvette Cendes @whereisyvette.bsky.social · 07/10/2026
My name (and research) is in today’s edition of the @nytimes.com! 🤩 🔭🧪🎢
814317
Reposted by Predrag Cvitanović
Philip Ball @philipcball.bsky.social · 06/10/2026
Echoes here of Rainer Weiss and LIGO from the 2017 Nobel. Sometimes you have to think boldly, even a little crazily.
0214
Reposted by Predrag Cvitanović
Nicole Rust @nicolecrust.bsky.social · 07/10/2026
Just like that: poof & gone. RIP *all* of NSF social, behavioral and economic research (including psyc & cogneuro). I’m speechless.
814363
Reposted by Predrag Cvitanović
Geoff Brumfiel @gbrumfiel.bsky.social · 06/10/2026
The IceCube neutrino detector has won the 2026 Nobel Prize in physics. The Trump administration has proposed slashing its budget in half in 2027.
382020705
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 06/10/2026
While we wait for this year's #NobelPrize in physics, check out our coverage of notable past prizes. This year, we're telling the stories of the first physics Nobel laureates from selected countries. First up: C V Raman, the first Indian physics laureate. physicsworld.com/a/c-v-raman-... 🧪⚛️
physicsworld.com
C V Raman: the physicist with a 'Himalayan ego' who went to Stockholm convinced he’d win a Nobel prize – Physics World
Preetish Kakoty describes why India's only Nobel-prize-winning physicist went to Sweden on a whim
382
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 06/10/2026
This year's #NobelPrize in Physics has gone to Francis Halzen "for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin". This was our "breakthrough of the year" in 2013: physicsworld.com/a/cosmic-neu... 🧪⚛️
physicsworld.com
Cosmic neutrinos named Physics World 2013 Breakthrough of the Year – Physics World
IceCube experiment at the South Pole tops our list of the 10 key breakthroughs in physics
3278
Reposted by Predrag Cvitanović
Nobel Prize @nobelprize.org · 06/10/2026
BREAKING NEWS The Royal Swedish Academy of Sciences has decided to award the 2026 #NobelPrize in Physics to Francis Halzen “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin.”
8505255
Reposted by Predrag Cvitanović
Laura Baudis @lbaudis.bsky.social · 06/10/2026
I am so happy today for Francis Halzen and for the IceCube collaboration. The Nobel Prize for Francis, for IceCube, and for high-energy neutrino astronomy is very special for me, both scientifically and personally.
1202
Reposted by Predrag Cvitanović
Sean Carroll @seanmcarroll.bsky.social · 06/10/2026
Such a good Nobel Prize! Francis Halzen is a great person, and “let’s turn the Antarctic ice sheet into a neutrino detector” is the kind of idea that deserves a Prize if you can pull it off.
318029
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 06/10/2026
A rare solo #NobelPrize in physics goes to neutrino scientist Francis Halzen “for decisive contributions to the IceCube Neutrino Observatory and the discovery of high-energy neutrinos of astrophysical origin”. Full coverage here: physicsworld.com/a/francis-ha... 🧪⚛️
physicsworld.com
Francis Halzen wins Nobel Prize in Physics – Physics World
Astrophysicist wins for his work detecting cosmic neutrinos
2325461
Reposted by Predrag Cvitanović
Dan Garisto @dangaristo.bsky.social · 06/10/2026
NEW: In March the White House released an FY27 budget request that zeroed out the National Science Foundation's directorate of Social, Behavioral and Economic Sciences (SBE). For months it was unclear what would happen. Now, with FY26 over, the damage to SBE is coming to light. My reporting:
science.org
‘Complete devastation’: How NSF gutted its social sciences research
Agency body that funds sociology, linguistics, and archaeology studies in U.S. gave 90% fewer new grants this year
9661515
Reposted by Predrag Cvitanović
Applied Physics Express and JJAP @apexjjap.bsky.social · 04/10/2026
[Spotlights:2024 OPEN ACCESS] Demonstration of UV-A stimulated emission from optical pumping with a nano-porous cladding layer 2024 Appl. Phys. Express 17 122001 iopscience.iop.org/article/10.3... Spotlights iopscience.iop.org/journal/1882... #APEX #Physics #OA #オープンアクセス #GaN #Ultraviolet #Diode
041
Reposted by Predrag Cvitanović
David Ho @davidho.bsky.social · 03/10/2026
I don’t think everyone realizes how bad things are for US science: For the fiscal year that just ended, the Trump regime withheld $1.4 billion from the National Science Foundation’s research budget, which is about 1/5 of its primary research budget.
nytimes.com
National Science Foundation Diverted $1.4 Billion in Science Funds Mandated by Congress (Gift Article)
The move, affecting about one-fifth of the National Science Foundation’s primary research budget, is the latest sign of how the White House is asserting more control over grants.
201844915
Reposted by Predrag Cvitanović
James Webb 🔴 Gallery @webb-telescope.bsky.social · 03/10/2026
NASA's James Webb Space Telescope on Flickr (Jan 2, 2024) Early galaxies exhibit unexpected shapes, from spheres to surfboards, as revealed by Webb's detailed observations. flic.kr/p/2psZzHi
Illustrations of distant galaxy shapes appear in quadrants, showing 3D objects and cross sections of various forms. Credit: Viraj Pandya (Columbia), Haowen Zhang (University of Arizona), Lucy Reading-Ikkanda (Simons Foundation), NASA, ESA, CSA, Joseph Olmsted (STScI)
1103
Reposted by Predrag Cvitanović
Physics Today @physicstoday.aip.org · 02/10/2026
The postwar funding boom in US physics came to a halt at the end of the 1960s, when officials in the Nixon administration made major cuts to the federal science budget. As historian Julia Menzel of @ihpst-uoft.bsky.social notes, the lessons learned then may be helpful to today’s scientists. #histSTM
physicstoday.aip.org
The last crisis of US physics
At the end of the turbulent 1960s, the postwar funding boom in US physics came to a crashing halt. The lessons learned then may be helpful to today’s physicists.
22016
Reposted by Predrag Cvitanović
Will Thomas @williamthomas.bsky.social · 02/10/2026
In today's AIP History Weekly Edition, we look at a new volume on the long history of efforts to measure the effects of general relativity. It showcases extraordinary efforts to secure high-precision measurements and adds to our understanding of GR's acceptance, neglect, and renaissance. #HPS
aip.org
Book spotlight: Testing Einstein
AIP History Weekly Edition: October 2, 2026
0157
Reposted by Predrag Cvitanović
Nigel Goldenfeld @nigelgoldenfeld.bsky.social · 03/10/2026
🧪 "Mr. Trump’s science adviser, Michael Kratsios, has criticized the agency’s system for deciding which grants to fund ... He also argued the N.S.F. should ... bypass external review panels.” Kratsios lost 90% of assets while CFO of Clarium Capital. Do you trust him with the US science portfolio?
nytimes.com
National Science Foundation Diverted $1.4 Billion in Science Funds Mandated by Congress
The move, affecting about one-fifth of the National Science Foundation’s primary research budget, is the latest sign of how the White House is asserting more control over grants.
23423
Reposted by Predrag Cvitanović
Joshua Weitz @joshuasweitz.bsky.social · 01/10/2026
From July 2026 and relevant to this thread... on nihlism and interpreting where the money is going as being just as important as where the money is coming from.
joshuasweitz.substack.com
Decoy effects and the White House vision of transferring federal funding of science to corporate interests
Why a recent call to abolish the NIH is a decoy to accelerate the OSTP-endorsed transfer of federal science funding to corporate interests
131
Reposted by Predrag Cvitanović
Dan Garisto @dangaristo.bsky.social · 01/10/2026
OMB's focus on NIH and NSF, which has confused a lot of folks, pretty much boils down to stopping money going to universities.
1227141
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 01/10/2026
Next time you brush your teeth, comb your hair, switch on a light or ride on a bus, spare a thought for tribologists and their dedication to making the world run smoothly. Honor Powrie thinks it’s hard to think of anything that doesn’t involve tribology at all. 🧪⚛️ physicsworld.com/a/the-secret...
physicsworld.com
The secret world of tribology – Physics World
Honor Powrie pays tribute to the work of tribologists
1194
Reposted by Predrag Cvitanović
Physics World @physicsworld.bsky.social · 01/10/2026
Physicists have experimentally reconstructed the quantum probability distribution of an exciton for the first time using super-fast time-resolved photoemission orbital tomography. 🧪⚛️ physicsworld.com/a/exciton-wa...
physicsworld.com
Exciton wavefunctions come into view – Physics World
New work could lead to improvements in organic photovoltaics
0112
Reposted by Predrag Cvitanović
Prof Anna Watts @profannawatts.bsky.social · 01/10/2026
Been doing neutrinos with my Astrophysics class, this is a very cool new result! physics.aps.org/articles/v19...
physics.aps.org
Gallium Anomaly May Finally Be Explained
A decades-old neutrino mystery might be solved not by undiscovered physics but by improved calculations.
1203
Reposted by Predrag Cvitanović
Naomi Oreskes @naomioreskes.bsky.social · 30/09/2026
This is demoralizing. I love science as much as anyone--and have spent a good part of my career defending it--but if we (should have) learned anything from the Covid-19 pandemic, it's that natural science without humanistic perspectives often fails to hit its mark. news.harvard.edu/gazette/stor...
news.harvard.edu
Harvard launches $150 million research initiative— Harvard Gazette
University plans range of awards in basic and applied science, seeking to meet "moment of remarkable opportunity."
2233
Reposted by Predrag Cvitanović
Nigel Goldenfeld @nigelgoldenfeld.bsky.social · 01/10/2026
NSF announces a new branding page. "You shared your feedback — we listened!" WTF content.govdelivery.com/accounts/USN... At the end of FY 2026, NSF has made 6218 awards compared to 11,387 average in previous years. Thx @grantwitness.org If you're listening NSF, how about doing your job?
Graph of NSF awards for FY 2021-2026 showing that at the end of FY 2026, NSF has made about half the usual number of awards.
01911
Reposted by Predrag Cvitanović
Michael Warburton @michaelwarburton.bsky.social · 30/09/2026
She escaped her Nazi husband (disguising herself as her own maid became a Hollywood star, then co-developed a radio guidance system for Allied torpedoes - the principles of which are incorporated into today’s Bluetooth & GPS technology. BOMBSHELL: THE HEDY LAMARR STORY (2017)
482201515
Reposted by Predrag Cvitanović
Eugene Vinitsky 🍒 @eugenevinitsky.bsky.social · 30/09/2026
Preparing a lecture on the practice of research and was reminded of this lovely essay on the importance of being comfortable with feeling stupid: fermatslibrary.com/s/the-import...
fermatslibrary.com
Fermat's Library | The importance of stupidity in scientific research annotated/explained version.
Fermat's Library is a platform for illuminating academic papers.
3255
Reposted by Predrag Cvitanović
Hoodlum 🇺🇸 @nothoodlum.bsky.social · 30/09/2026
NEW: Meta found a way to turn massive data centers into “pilot models” and cash in on a 1980s tax credit. The result? Meta avoided nearly $4 billion in taxes last year alone. Gift link. 👇 www.nytimes.com/2026/09/30/t...
nytimes.com
How Meta Uses A.I. Data Centers to Avoid Billions in Federal Taxes (Gift Article)
Meta is exploiting a lucrative tax break intended to support research and experimentation. Its own accountants say the gambit is risky.
20735742297
Reposted by Predrag Cvitanović
Anthony (Tony) J. Martin @ichnologist.bsky.social · 30/09/2026
For Atlanta-area folks who also love books: the annual Decatur Book Festival in downtown Decatur GA is this weekend! Keynote talks are this Friday (Oct. 2) & most author events are Saturday (Oct. 3). Here's the schedule, authors, map, & more: www.decaturbookfestival.com/session-sche... #Booksky 📚✍️
decaturbookfestival.com
SCHEDULE | DBF
2026 Decatur Book Festival Schedule
061
Reposted by Predrag Cvitanović
Miska Knapek @miskaknapek.bsky.social · 29/09/2026
UK Meteorological Office bringing 3d data visualisation #datavis to the next level #datascience well done :D
0104
Predrag Cvitanović @chaosbook.bsky.social · 29/09/2026
www.adamkinzinger.com/p/the-space-...
adamkinzinger.com
The Space Race You Never Heard About
Scientists raced to finish a new telescope before Trump could cancel the funding. And they won.
011
Reposted by Predrag Cvitanović
Dr Katie Twomey @k2mey.eurosky.social · 28/09/2026
This is quite cool. My university is the first organisation in the world to force Microsoft to allow us to turn off copilot summaries in Word 365, after a backlash against it from staff (including, very vocally, me). That cannot have been easy for our heroic IT people so hats very much off to them!
895443936
Reposted by Predrag Cvitanović
Philip Ball @philipcball.bsky.social · 28/09/2026
"I believe that science derives its authority from something more than mastering the pipeline from data generation to publication. Rather, it comes from interactions within a community of people trained to interrogate evidence and answer for the conclusions they draw from it." Brandon is spot on.
13810
Reposted by Predrag Cvitanović
Joshua Weitz @joshuasweitz.bsky.social · 28/09/2026
Wonderful profile of our new colleague in the Dept. of Biology in Maryland, @couchmicroscopy.bsky.social with secrets yet to be uncovered into a major evolutionary transition hanging out in murky waters. www.nytimes.com/2026/09/26/s...
nytimes.com
In an $80 Motel Room, a Discovery to Shed Light on the Origins of Life (Gift Article)
A scrappy science project led to a significant discovery: two new species of a rare organism that could elucidate a fundamental transition in the history of life on our planet.
33914
Reposted by Predrag Cvitanović
Robert "The Bobby Yaga" McNees @mcnees.bsky.social · 28/09/2026
Astronomer and mathematician Pierre-Louis Moreau de Maupertuis, exact date of birth unknown, was born around this time in 1698 and baptized #OTD. He was among the first to articulate the Principle of Least Action, one of the most beautiful ideas in physics. 🧪 ⚛️ Image: Wellcome Trust
Etching of Maupertuis. His right hand rests on a globe and his left hand points to the site like a manicule from a broadsheet. He has a long, dark, curly wig on, and a robe tied at the waist with a sash.
15012
Reposted by Predrag Cvitanović
Alt CDC (they/them) @altcdc.altgov.info · 28/09/2026
💡Did you know that on September 28, 1928, a Scottish physician named Sir Alexander Fleming discovered the antibiotic penicillin?
29427
Reposted by Predrag Cvitanović
Philip Ball @philipcball.bsky.social · 27/09/2026
Very good to see this place again too.
The Niels Bohr Institute, Copenhagen
1241
Reposted by Predrag Cvitanović
Joshua Weitz @joshuasweitz.bsky.social · 28/09/2026
“I’ve heard from a bunch of people in our field who say, ‘Uh oh, are they training on my prompts?’” Dr. Shipman said. “We can’t not think about it.” ... '[A]fter Anthropic’s announcement last week, he is winding down his projects with Claude.' “I’m shutting down everything,” [Dr. Mestre] said.
57530
Reposted by Predrag Cvitanović
David Ho @davidho.bsky.social · 27/09/2026
The techbros don't want you to see this trailer. Pass it on.
3249762755
Reposted by Predrag Cvitanović
𝕯𝖆𝖓🍂🎃🕸️ @arepublic86.bsky.social · 28/09/2026
For reference, Voyager 1 launched in September 1977, and on November 18 of this year it will finally hit one light day. 49 years for one light day.
361060310