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David Bindel

@dbindel.bsky.social

1K followers 640 following 640 posts

Professing computing and applied math at Cornell. Numerical methods for data science, plasma physics, other stuff depending on the day. Director, Cornell Center for Applied Mathematics; Director, Simons Collaboration on Hidden Symmetries and Fusion Energy.

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David Bindel @dbindel.bsky.social · 5d

Things are all pear-shapes, and yet, I got some bunny paper clips along with my order of whiteboard marker refills, and that sparks joy.

Reposted by David Bindel

Paysages Mathématiques @paysmaths.bsky.social · 9d

"There are lots of problems in mathematics that are interesting but have not been solved, and every time you solve one you think up a new one. Mathematics, therefore, is something that expands rather than contracts." – Mary Ellen Rudin (1924– 2013)
#quote #mathematics #problems #maths #math

Quote from Mary Ellen Rudin : "There are lots of problems in mathematics that are interesting but have not been solved, and every time you solve one you think up a new one. Mathematics, therefore, is something that expands rather than contracts."

David Bindel @dbindel.bsky.social · 8d

Also got to have lunch with a former student of mine yesterday. Time flies.

David Bindel @dbindel.bsky.social · 8d

On the AC Transit to Berkeley for day 3 of Developments in Modern Methods for Linear Algebra... aka DMML, aka happy 70th to my PhD advisor, Jim Demmel.

Realized that I am now the same age he was about halfway through my PhD years...

Reposted by David Bindel

ChûgFromABigHûgMûg @bghgmg.bsky.social · 10d

gender norms admit the existence of gender metrics which can be abstracted to gender topologies which, here, we categorify into gender locales, also known as pointless genders

David Bindel @dbindel.bsky.social · 14d

- Asvine just released a new pen! The V800 is very pretty. I don't need more fountain pens, but can still admire.
- I get to check out a CT scanner setup tomorrow! Research reasons, nothing medical.
- The CAM students remain an excellent community. They did tie-dye shirts today.

David Bindel @dbindel.bsky.social · 14d

- I am learning about the mechanics of hair! Which is also awesome.
- Apparently, thinking these things are awesome is a thing the administration now thinks can be cured with Vitamin B. My vitamin B levels are fine, and I am happy they are wrong (even if I wish they were less in my face about it).

David Bindel @dbindel.bsky.social · 14d

- I am also writing a recommendation for a postdoc, who is awesome and should land that faculty job he wants. And if the market sucks, well, I am still happy he's awesome and working some of the time with me.

David Bindel @dbindel.bsky.social · 14d

- I am astounded that I don't yet have a better alternative than TikZ and dvisvgm for programmatically producing the titles of math diagrams I want for notes and slides, and it's fun to Google variations of "really?" in the hopes of finding a different answer.

David Bindel @dbindel.bsky.social · 14d

- My background music is K2 singing in the shower.
- I spent time redoing lecture notes today, and am enjoying the process.
- Next weekend is the DMML meeting, aka JimFest -- in honor of my advisor (a) retiring and (b) turning 70. Looking forward to a couple days in the Berkeley.

David Bindel @dbindel.bsky.social · 14d

In a day of wtf nat'l news moments (again!), I also know:
- Today was AppleFest in Ithaca! And yesterday, and tomorrow.
- K1 is out enjoying a concert, and has been noodling around on his guitar all week.
- K2 just got back from playing basketball and is heading to a sleepover soon.

Reposted by David Bindel

NightMar on Hicks Street, Part 4: The Rabbit’s Revenge @histoftech.bsky.social · Jun 15

Your daily opossum break:

Reposted by David Bindel

Janel Comeau 🍁 @verybadllama.bsky.social · 19d

I have taken
the Tylenol
that was in
the medicine cabinet

and which
they think probably
is the reason
you like trains

forgive me
but that’s bullshit
you got autism
from your dad

David Bindel @dbindel.bsky.social · 20d

I approve of books and bunny (?) both!

David Bindel @dbindel.bsky.social · 24d

This generalizes beyond n=2, but that's just a little longer than one skeet!

David Bindel @dbindel.bsky.social · 24d

Consider m=2. If switching arguments switches sign, then f(u,u)=-f(u,u), so f(u,u)=0. Conversely, suppose f(u,u)=0 for all u. Then f(u,v)+f(v,u)=f(u,v)-2f(u,u)+f(v,u)=f(u-u,v)+f(v,u-u)=0. So zero if two entries the same is equivalent to changing signs of two arguments are swapped.

David Bindel @dbindel.bsky.social · 24d

A function of n vectors, linear in each argument, such that swapping any pair of arguments changes the sign.

David Bindel @dbindel.bsky.social · 24d

Up to a scale factor. On an n-dimensional space, there is only a one-dimensional family of alternating n-forms. The determinant is the basis vector for that space that yields 1 when applied to the standard basis for Rn.

Reposted by David Bindel

NY-CURES @nycures.bsky.social · Sep 4

🚀 NY-CURES Launch — Championing State-Wide Investment in Science! 🚀

Our new coalition advocates for sustained public support of New York’s vibrant biomedical research ecosystem — creating cures, economic gains & strengthening communities.

Sign up. Stay informed. Join the movement: www.nycures.org/

Reposted by David Bindel

Bill Kristol @billkristolbulwark.bsky.social · 28d

It should be needless to say, but it is perhaps at this moment worth saying, that transgender individuals have the same right as anyone else to life, liberty, and the pursuit of happiness.

Reposted by David Bindel

Chanda Prescod-Weinstein 🌌 @chanda.blacksky.app · Sep 12

This fucking sucks. Our Chinese colleagues are valued colleagues. I am so tired of the bipartisan yellow threat shit. www.cnn.com/2025/09/11/s...

Trump admin escalates space race with China, banning visa-holding scientists from working at NASA | CNN

NASA has banned Chinese citizens with US visas from participating in agency programs — a dramatic escalation in the space race between China and the United States.

Reposted by David Bindel

Maria Popova @mariapopova.bsky.social · Aug 28

The great Zen teacher Thich Nhat Hanh's poetic antidote to anger www.themarginalian.org/2022/02/01/f...

David Bindel @dbindel.bsky.social · Aug 27

Also: "the super banana orbits" should be a band name for someone, somewhere.

David Bindel @dbindel.bsky.social · Aug 27

There does exist techno-babble-sounding jargon in the world. But then there's technical jargon as captured from a research conversation today: "I'm tracing long enough to capture many bananas." Plain, short, descriptive... and yet, it takes some experience to have any clue what's being said.

Reposted by David Bindel

Assistant HR Director of Antifa @sethdmichaels.bsky.social · Aug 14

(long, reluctant sigh)

sub-terfuge

Tess Owen @tessowen.bsky.social · Aug 14

Attorney General Pam Bondi says that the "Subway Slinger" who chucked a sandwich at a federal agent in DC the other night is actually a DOJ employee. She describes him as an "example of the deep state."