Astrophysicist @ the Center for Computational Astrophysics & U Washington. PI of the Panchromatic Hubble Andromeda Treasury (PHAT). @dalcantonjd@bsky.social

Joined January 2012
Replying to @dalcantonJD
Compared to the professionally crafted dog on the left, my dog is an episode of “Nailed it”.
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Julianne Dalcanton retweeted
I think a big issue these guys are going to have is learning that both the hardest problems in the world (and the biggest problems in daily living) can't be solved by using the computer better
Dusting off this tweet from April because this gap in shared understanding of LLM capability is *widening*. It's now less "two groups of people speaking past each other" and more a sharp funnel. - Napkin math somewhere around 6B people (~75% of the population) have barely come in contact with LLMs at all. - Around 1-2B (~20%) are casual and infrequent users of free-tier ChatGPT-like products. This group sees derpy chatbots and treats them a bit like a better Google search, a writing aid, or etc. Maybe an agent tries to book you a flight. I have non-tech friends who (reasonably, imo) say they have not much use for it at all. Even many professionals outside of math&code are in this tier. For example, execs and many other functions spend a lot of their time talking to other people, so while they understand what is happening intellectually, it is still second-hand and a bit abstract. - Now we get to professional use of frontier-grade LLMs in math&code. Somewhere around 20M people (0.2%) see first-hand that large, complex projects that used to take them weeks/months can now be completed by agents with a prompt. Building apps, copying apps, translating apps, decompiling apps from binaries... This has all happened very quickly and recently - less than 1 year ago, I was writing code manually by hand, typing memorized computer code commands into a code editor character by character, occasionally pressing Tab to autocomplete a little chunk of code. - And finally we get to the ~5,000 people (~0.00006%) with access to frontier-grade systems internally. The external world has seen the preview. It looks like swarms of thousands of agents collaborating over weeks on software mega projects: minting zero days, running cyber attacks and defenses at machine speeds, discovering new science, advancing the frontier of mathematics. Things that would have taken top professionals in the industry years of work. Meanwhile, human review and comprehension are starting to fall behind. For example, people are still involved in the "archeology" of the OpenAI-HF incident from many months ago. Mathematicians may be poring over the 722 manuscripts on frontier mathematics for a while. The funnel is driven by a combination of factors: 1. The impact scales with ambition, problem size, and horizon. A question with a paragraph answer barely stresses the system. You need a reservoir of big, difficult problems that you really care about. This aspect drives the consumer / professional dimension of the funnel. 2. The jaggedness of the system (which I have written about a lot separately). Capability peaks in domains that are digital, verifiable and economically valuable. This is because LLM capability emerges from reinforcement learning on verifiable rewards on a curated environment mixture driven by revenue potential. This aspect primarily drives the area (e.g. math&code) dimension of the funnel. 3. Access. Free-tier, paid-tier, internal. So this is the weirdness of the moment. The general public has mostly not interacted with these systems. When they have, it looks like a derpy chatbot. The majority of professionals still see only a modest uplift. And a small sliver of professionals are experiencing the vertigo of the curve going vertical. And it is all happening at the same time.
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Julianne Dalcanton retweeted
The real phenomenon behind of a lot of claims of “bloat” in academia is not the expense of bureaucracy but that its pervasiveness feels like a change in the character of the job of faculty. chadorzel.substack.com/p/the…
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Julianne Dalcanton retweeted
If you ever doubt how magical this world is, one day you will decide to go to a World Cup watch party in Oakland that you found online to root for a country where you spent two years trying to coax English out of the mouths of Cape Verdean teenagers. 1/7
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Julianne Dalcanton retweeted
TODAY
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Julianne Dalcanton retweeted
NYU Center for Data Science just got a major level-up. 📈✨ CDS is officially a full-fledged Department within the new Courant Institute School—and we need an Inaugural Chair to hold the keys. Wanted: A visionary to lead the best in the biz in the city that never sleeps. 🗽 Is it you? Or do you know the person who belongs at the head of the table? Check out the most exciting job in academia right now: 🔗 apply.interfolio.com/179190 #NYU #DataScience #AcademicTwitter #Hiring #BigData #NYC
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Julianne Dalcanton retweeted
So proud to see the culmination of effort led by @mikemccabe210 @PayelMukhopadh3 @__tm__157 @BrunoRegaldo @FrancoisRozet along with the amazing team at @PolymathicAI to produce The first "Polymathic"/cross-disciplinary AI model for fluid dynamics! We started with creating The Well, the first internet scale of fluids dataset co-led by @mikemccabe210 and @oharub with the goal of creating the first cross-disciplinary fluid model! Now it is here, and we are lovingly naming it the Polymathic Walrus 😁!
1/ Today with my colleagues @PolymathicAI, I'm excited to release our latest project, Walrus, a cross-domain foundation model for physical dynamics, into the world. polymathic-ai.org/blog/walru… Paper: arxiv.org/abs/2511.15684 Git: github.com/PolymathicAI/walr… HF: huggingface.co/polymathic-ai…
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Julianne Dalcanton retweeted
🚀We’re looking for 2026 interns at @PolymathicAI (NYC)! Want to work on scientific foundation models + ML for physics, biology, astronomy, & more? Want to contribute to frontier research with a brilliant, fun, and friendly team? Please sign up on our interest form 👉 forms.gle/hxXPCv3qssEkEQJT7 #Hiring #Internship #MachineLearning
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Julianne Dalcanton retweeted
I’m excited to announce that @PolymathicAI new astrophysics model, AION-1, has been accepted to #neurips2025 ! 🎉 Come see our poster on Dec 5 (Friday) at 1-4pm PT, poster session 5 OR hear our talk from @liamhparker and Francois Lanusse at #AI4Science workshop It’s the first large-scale multimodal foundation model for astronomy!
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Julianne Dalcanton retweeted
announcing dora.nyc - A directory of resources and aid for NYC. use / distribute / add
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Julianne Dalcanton retweeted
I live on Canal Street and I think you’re a piece of shit
I personally had New Yorkers thanking me for bringing light to how bad Canal street has gotten. Illegal immigration and the crime tied to it have been plaguing your city, I make no apologies for reporting on what real New Yorkers have to deal with every single day.
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Julianne Dalcanton retweeted
The clamp down is about producing content as much as anything else
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Julianne Dalcanton retweeted
Also, you need to understand that Trump's grotesque fascist abuses are almost always in order to produce social media content like this. Why did ICE conduct such an insane military raid on a random apartment building and arrest a bunch of US citizens? For this video.
Chicago, we’re here for you.
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ICE rappel from Black Hawk helicopters—detain U.S. citizens. Grab everyone at apartment complex—even zip tie the children together. "They had the Black people in one van, and immigrants in another van," said witness. "One agent literally laughed... He said, 'F them kids.'" Trucks and military style vans were used to separate the children from their parents—destroying neighborhood property in the process. "My building was shaking... Then I looked out the window, and it's a Black Hawk helicopter!" said another witness. "We're under siege. We're being invaded by our own military." ICE released statement saying the raid went "smoothly," and was "targeted" to find gang members at the apartment complex on the south side of Chicago. #DemsUnited
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Julianne Dalcanton retweeted
Ohhhhh it's a bribery scheme.
Critical part of the President's new $100,000 charge for H1-B visas: The Administration can also offer a $100,000 discount to any person, company, or industry that it wants. Replacing rules with arbitrary discretion. Want visas? You know who to call and who to flatter.
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Julianne Dalcanton retweeted
We're hiring Flatiron Research Fellows & Software Fellows at the @FlatironInst CCA. These independent postdoc positions offer outstanding opportunities for collaboration, computation, and scientific growth in NYC: apply.interfolio.com/173402 apply.interfolio.com/173403
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Julianne Dalcanton retweeted
Runaway winner for the most gorgeous paper of the year! Thanks to @dalcantonJD, Meredith Durbin, and Ben Williams!
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Julianne Dalcanton retweeted
One of the most important contributions to the study of how stars evolve didn’t come from an astrophysicist, but instead a computer scientist. Bill Paxton — who died last month — revolutionized the field by creating the Modules for Experiments in Stellar Astrophysics (MESA). Read more about Paxton's life and MESA: simonsfoundation.org/2025/08… #science #astrophysics
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Julianne Dalcanton retweeted
Ending the summer with presentations from our interns on the research they worked on over the past few months. Learn more about our summer internship program: simonsfoundation.org/summer-… #science
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Julianne Dalcanton retweeted
Kamala Harris at her closing campaign rally: "Donald Trump intends to use the United States Military against American citizens who simply disagree with him."
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