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Ben Grant

@bengrantmath.bsky.social

PhD candidate in math at UConn. Interested in cluster algebras, representation theory, algebraic combinatorics, dimer models, knot theory, and logic. he/him/his https://sites.google.com/view/benjamingrant

334 Followers  |  292 Following  |  67 Posts  |  Joined: 04.07.2023  |  2.2161

Latest posts by bengrantmath.bsky.social on Bluesky

from now on I'm just going to truncate the taylor series for sin at the first term. sin(x) = 0 for all x. this approximation

- is efficient to compute
- has bounded error
- has excellent analytic properties
- has very high accuracy for small values, which occur frequently in applications

08.10.2025 17:21 β€” πŸ‘ 28    πŸ” 5    πŸ’¬ 1    πŸ“Œ 0

the award or an HM, but because it feels like this reviewer didn’t take my application seriously at all, and I worry that I’m not the only person this happened to. End of rant, thanks for reading.

04.10.2025 12:30 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

algebraic combinatoricsβ€” this reviewer was leaving comments about my desire to do research in β€œset theory,” about β€œsupercompactness,” and about β€œthe combinatorics of the first singular cardinal.” I did not mention any of these whatsoever.

I am mostly just disappointed, not because I didn’t receive

04.10.2025 12:30 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

were almost directly copied but with additional typos that I didn’t make (???), but by far the most annoying part to me is that other bullet points were about things that I just *did not talk about at all* in my application. For context, the focus of my proposal was in representation theory and

04.10.2025 12:30 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

detailed reviews that demonstrated they, at a minimum, read and thought about my statement and proposal. The third reviewer, on the other hand, left as their comments a relatively incoherent mix of bullet-point-style remarks. Some of these points were directly copied pieces of my statements, some

04.10.2025 12:30 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Very mild rant. GRFP reviews from last year’s application cycle came out a couple days ago. I applied last year but did not receive the award or an honorable mention (oh well, this happens, not the part that’s frustrating). Two of the three reviewers assigned to my application left very positive,

04.10.2025 12:30 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

question, but it seems (to me) like a very natural point of view nonetheless.

12.09.2025 23:13 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

the β€œregular functions” on A^n into an object R_n (i.e., taking R_n=Hom(A^n,A)) should give you the β€œalgebraic” dual of the β€œgeometric” A^n. Then duals of mappings f:A^nβ€”>A^m are just their images f^*:R_mβ€”>R_n under Hom(-,A).

I am not sure if this gives a reasonable answer to the original duality

12.09.2025 23:13 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

This is perhaps naive and not-so-well-thought-out, but it seems to me like the question here might be interesting to look at from an algebraic geometry perspective. Morphisms A^nβ€”>A appearing in an algebraic structure might be understood as β€œregular functions” on A^n as an β€œaffine space.” Collecting

12.09.2025 23:13 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Ah, I see that someone else already beat me to this

09.09.2025 21:13 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

understanding) one of the starting points of gauge theory

09.09.2025 21:06 β€” πŸ‘ 0    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Correct me if I’m mistaken (I don’t know much physics), but I think what you’re talking about is that there are lots of different connections on the (trivial) fiber bundle R^3xR->R. Different connections give different ways of identifying points in different fibers. This is (to my very limited

09.09.2025 21:06 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Ah okay, I believe this works! I think (sort of like Brendan’s argument) this gives an embedding of the poset of functions [0,1) β†’ ℝ ordered pointwise into the poset of all O(f) (given by (Ξ± ↦ r_Ξ±) ↦ O(the function you described))

03.09.2025 19:57 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

I like this a lot!

03.09.2025 19:51 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Not sure about the partial order you get for arbitrary functions ℝ β†’ ℝ, though. Certainly there are 2^c of these functions, but maybe it’s possible the poset of O(f) is strictly smaller?

03.09.2025 19:34 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

There are only c functions β„• β†’ ℝ, and this set surjects onto the partial order you’re interested in, so it has cardinality c. If you’re interested in continuous or smooth functions ℝ β†’ ℝ, there are also only c of these (by continuity, they’re determined by what values they take on β„š)

03.09.2025 19:32 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 2    πŸ“Œ 0

Daniel Labardini Fragoso: Derksen-Weyman-Zelevinsky mutations of infinite-dimensional modules I: Foundations https://arxiv.org/abs/2508.21757 https://arxiv.org/pdf/2508.21757 https://arxiv.org/html/2508.21757

01.09.2025 06:40 β€” πŸ‘ 1    πŸ” 3    πŸ’¬ 0    πŸ“Œ 0
Preview
Decompositions of augmentation varieties via weaves and rulings The braid variety of a positive braid and the augmentation variety of a Legendrian link both admit decompositions coming from weaves and rulings, respectively. We prove that these decompositions agree under an isomorphism between the braid variety and the augmentation variety. We also prove that both decompositions coincide with a Deodhar decomposition and another decomposition coming from the microlocal theory of sheaves. Our proof relies on a detailed comparison between weaves and Morse complex sequences. Among other things, we show that the cluster variables of the maximal cluster torus of the augmentation variety can be computed from the Legendrian via Morse complex sequences.

arxiv.org/abs/2508.20226
/Decompositions of augmentation varieties via weaves and rulings/
Johan Asplund, Orsola Capovilla-Searle, James Hughes, Caitlin Leverson, Wenyuan Li, Angela Wu

29.08.2025 02:02 β€” πŸ‘ 1    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
A screenshot of some of the lyrics to β€œ$0” by Cameron Winter on Spotify:

God is real
God is real
I’m not kidding
God is actually real
I’m not kidding this time I think God
is actually for real God is real
God is actually real God is real
I wouldn’t joke about this
I’m not kidding this time

A screenshot of some of the lyrics to β€œ$0” by Cameron Winter on Spotify: God is real God is real I’m not kidding God is actually real I’m not kidding this time I think God is actually for real God is real God is actually real God is real I wouldn’t joke about this I’m not kidding this time

Man the lyricism here is something (excellent, beautiful song). I wouldn’t joke about this, I’m not kidding this time

29.08.2025 00:55 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Burn OpenAI to the ground.

26.08.2025 23:14 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0
Preview
SUBgroups Online peer groups for first-year math graduate students.

Registration for the SUBgroups program for first-year math grad students is now open!

Find out more and register here: gradsubgroups.org

Please share with any first-year math grad students you know who are looking for some regular peer support!

26.08.2025 19:16 β€” πŸ‘ 8    πŸ” 5    πŸ’¬ 1    πŸ“Œ 1

If I had a dollar for every time, I would have uncountably many dollars

26.08.2025 22:13 β€” πŸ‘ 3    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

β€œRecollements” do exactly this, I think

21.08.2025 13:50 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

HBO Max and Disney Plus are my favorite tropical semiring

19.08.2025 01:45 β€” πŸ‘ 3    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0
A picture of me holding a half-full cup of iced coffee from Caribou Coffee

A picture of me holding a half-full cup of iced coffee from Caribou Coffee

Layover in Denver on my way to a workshop in Oregon this week, excited to do some math and see some friends

17.08.2025 16:56 β€” πŸ‘ 7    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

They’ve put it all right back into sports.

14.08.2025 15:14 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

Roger Casals, Pavel Galashin, Mikhail Gorsky, Linhui Shen, Melissa Sherman-Bennett, Jos\'e Simental
Comparing cluster algebras on braid varieties
https://arxiv.org/abs/2508.03816

07.08.2025 05:44 β€” πŸ‘ 2    πŸ” 1    πŸ’¬ 0    πŸ“Œ 0

Totally and completely unrelated: if anyone can help me prove that a certain set is analytic but not Borel, let me know. I’ve tried finding a continuous reduction to it from the set of ill-founded trees in omega^<omega, but have not had any luck so far.

06.08.2025 03:21 β€” πŸ‘ 1    πŸ” 0    πŸ’¬ 0    πŸ“Œ 0

The one I have in mind is right at the sweet spot between logic and combinatorics, too, which is a place I always enjoy being

06.08.2025 02:08 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

Good feeling when you come up with a research question that (1) you have no idea how to tackle and (2) the answer is going to be interesting, no matter what it is

06.08.2025 02:03 β€” πŸ‘ 2    πŸ” 0    πŸ’¬ 1    πŸ“Œ 0

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