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Adrian Fraser @fraserlaser.bsky.social · 3d

(Oops, switch “upper” and “lower” in the above)

Adrian Fraser @fraserlaser.bsky.social · 3d

Hey astrophysicists, a presence (absence) of KH billows in some astrophysical shear flow doesn't always imply a lower (upper) bound on the local magnetic field strength! See arxiv.org/abs/2510.031...

Nonmodal growth and optimal perturbations in magnetohydrodynamic shear flows

In astrophysical shear flows, the Kelvin-Helmholtz (KH) instability is generally suppressed by magnetic tension provided a sufficiently strong streamwise magnetic field. This is often used to infer up...

arxiv.org

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Reposted by Adrian Fraser

NY Times Pitchbot @nytpitchbot.bsky.social · 16d

Trump is pronouncing "acetaminophen" the right way.

by Ezra Klein

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Adrian Fraser @fraserlaser.bsky.social · 25d

Friends, colleagues, my heart is heavy as I share with you some deeply saddening news: “asymptotically spicy” will not, in fact, survive to final publication of this manuscript. But it will live on in the arXiv preprint, at least

Adrian Fraser @fraserlaser.bsky.social · Apr 22

I’ve been looking at salt fingers in a particular limit where it becomes technically correct to describe the flow as “asymptotically spicy” and thus I am of course obligated to somehow state this in the paper

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Adrian Fraser @fraserlaser.bsky.social · 28d

Where do people study MHD turbulence in The Netherlands? Asking for a friend looking for a job

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Adrian Fraser @fraserlaser.bsky.social · Sep 5

It was a good point, though! There were some pertinent examples on academic twitter ca. 2020ish where the same point could’ve been made

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Adrian Fraser @fraserlaser.bsky.social · Aug 25

Just trying to prepare myself to argue why my research actually does align with the WH’s priorities

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Adrian Fraser @fraserlaser.bsky.social · Aug 25

Like most modern astrophysicists, Trump is quickly realizing that he can’t keep neglecting magnetic fields

Aaron Rupar @atrupar.com · Aug 25

Trump: "China intelligently went in and they sort of took a monopoly of the world's magnets. Nobody needed magnets until they convinced everybody 20 years ago, 'let's all do magnets.' There were many other ways that the world could have gone ... we're heavily into the world of magnets now."

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Adrian Fraser @fraserlaser.bsky.social · Aug 25

Suddenly thinking this old proposal idea might have a chance

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Adrian Fraser @fraserlaser.bsky.social · Aug 25

Accepted for publication in JFM Rapids 🎉

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Reposted by Adrian Fraser

Jameel Jaffer @jameeljaffer.bsky.social · Aug 20

If this continues, the most talented American students will want to study abroad, because they'll want to study with the most talented students and faculty from around the world, and those people won't want to come to the United States even if they can. www.nytimes.com/2025/08/20/u...

Trump’s Tactics Mean Many International Students Won’t Make It to Campus

www.nytimes.com

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Adrian Fraser @fraserlaser.bsky.social · Aug 17

NYT spelling bee takes all kinds of niche words but NOT “adiabatic”??? Anti-science sentiments from NYT in the Trump era, you hate to see it

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Reposted by Adrian Fraser

Darren Incorvaia @megadarren.bsky.social · Aug 15

BREAKING: The NIH director has ordered an immediate review of all the agency's research activities. Any projects that don't fit agency priorities "may be restricted, paused, not renewed, or terminated." My story:

NIH chief calls for immediate research review, dangling threat of project termination

Jayanta Bhattacharya, M.D., Ph.D., director of the National Institutes of Health (NIH), has called on the agency’s scientific leadership to immediately review all of their current and planned resea | ...

www.fiercebiotech.com

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Reposted by Adrian Fraser

Pam Herd @pamherd.bsky.social · Aug 7

So bad.The EO institutionalizes and intensifies the politicization of federal research funding. The provisions weaken scientific expertise in funding decisions and effectively cede control to political appointees. The basic logistics here will also further slow walk release of federal research funds

Jeremy Berg @jeremymberg.bsky.social · Aug 7

Well, this is a huge Executive Order power grab...

www.whitehouse.gov/presidential...

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Improving Oversight of Federal Grantmaking

By the authority vested in me as President by the Constitution and the laws of the United States of America, and to improve the process of Federal

www.whitehouse.gov

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Adrian Fraser @fraserlaser.bsky.social · Aug 6

Obnoxious!

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Adrian Fraser @fraserlaser.bsky.social · Aug 6

Inspired by a certain program I’m submitting to requiring TEN PAGES for TWO YEARS of support for ONE PERSON, while the RSURF requires FOUR PAGES for like 4-8 years plus additional support for a student and postdoc. Wild range

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Adrian Fraser @fraserlaser.bsky.social · Aug 6

The ratio (length of proposal in pages)/(years of funding awarded) is an important thing. Too large, and the proposal writing process feels like a waste of time if the program is competitive. Too small, and it’s hard to convince people you know your stuff. No idea what the optimal value is.

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Reposted by Adrian Fraser

jamelle @jamellebouie.net · Jul 29

the one thing i genuinely did not anticipate from this administration was its vicious, know nothing hostility to any and everything that might even be adjacent to science and scientific research. they genuinely one to destroy the entirety of the nation’s research capacity. and for what, exactly?

Michael Lowry @michaelrlowry.bsky.social · Jul 28

If you think I've forgotten about the hurricane satellites, think again. The Navy is permanently unplugging them this week, on the brink of the busiest stretch of the season. There's so much more to this story, and I have the latest scoop. ⬇️

Navy Set to Unplug Critical Hurricane Satellites this Week

Abrupt termination of satellite data by U.S. Department of Defense sends forecasters scrambling for a fix on the brink of the busiest stretch of the hurricane season

michaelrlowry.substack.com

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Adrian Fraser @fraserlaser.bsky.social · Jul 1

Fresh on the arXiv today: if you take a thermally stably stratified (AKA subadiabatic AKA Schwartzchild- & Ledoux-stable) layer and sprinkle just a tiny bit of salt on the top, the salt fingers that form drive a helical mean flow that twists them into corkscrews arxiv.org/abs/2506.22581

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Adrian Fraser @fraserlaser.bsky.social · Jun 29

Pass-through businesses, of which he owned one!

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Adrian Fraser @fraserlaser.bsky.social · Jun 28

What the things actually look like. First image is a volume rendering of the vertical velocity, which gets twisted about by the helical flow

Volume rendering from a fluid dynamics simulation shows several corkscrew-shaped structures dancing about each other

Figure from the paper shows snapshots of the corkscrew structures

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Adrian Fraser @fraserlaser.bsky.social · Jun 28

Submitted! See abstract in first image and highlighted text in second image

A screenshot of the first page of a paper on salt fingers. Abstract reads:

We study the dynamics of salt fingers in the regime of slow salinity diffusion (small inverse Lewis number) and strong stratification (large density ratio), focusing on regimes relevant to Earth’s oceans. Using three-dimensional direct numerical simulations in periodic domains, we show that salt fingers exhibit rich, multiscale dynamics in this regime, with vertically elongated fingers that are twisted into helical shapes at large scales by mean flows and disrupted at small scales by isotropic eddies. We use a multiscale asymptotic analysis to motivate a reduced set of partial differential equations that filters internal gravity waves and removes inertia from all parts of the momentum equation except for the Reynolds stress that drives the helical mean flow. When simulated numerically, the reduced equations capture the same dynamics and fluxes as the full equations in the appropriate regime. The reduced equations enforce zero helicity in all fluctuations about the mean flow, implying that the symmetry-breaking helical flow is spontaneously generated by strictly non-helical fluctuations.

Screenshot of a later part of the paper, where the phrase “the dynamics are neutrally buoyant (or asymptotically spicy)” is slipped in and highlighted

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Adrian Fraser @fraserlaser.bsky.social · Jun 19

I have a coauthor who is extremely skilled at cutting down text to fit a word/page limit, and I’m immeasurably pleased to see that they’ve retained “asymptotically spicy” in the draft

Adrian Fraser @fraserlaser.bsky.social · Apr 22

I’ve been looking at salt fingers in a particular limit where it becomes technically correct to describe the flow as “asymptotically spicy” and thus I am of course obligated to somehow state this in the paper

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Reposted by Adrian Fraser

derek guy @dieworkwear.bsky.social · Jun 12

The cruelty in today's politics feels horribly corrosive. Bringing up that hard-working immigrant families — undocumented, yes, but not violent criminals — are being ripped apart based on immigration status doesn't bring compassion or even pause, but gleeful cheers.

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Reposted by Adrian Fraser

Adam Sternbergh @sternbergh.bsky.social · Jun 5

must be incredibly frustrating and disheartening to have federal funding that was promised to you for important work suddenly and arbitrarily ripped away

Best of Dying Twitter @bestofdyingtwit.bsky.social · Jun 5

“In light of the President's statement about cancellation of my government contracts, @SpaceX will begin decommissioning its Dragon spacecraft immediately”

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