Tootfinder

Steinberg skein identities at roots of unity
Vijay Higgins, Indraneel Tambe
https://arxiv.org/abs/2509.05502 https://arxiv.org/pdf/2509.05502

Steinberg skein identities at roots of unity
We obtain a family of skein identities in the Kauffman bracket skein module which relate Frobenius elements to Jones-Wenzl projectors at roots of unity. We view these skein identities as certain incarnations of Steinberg tensor product formulae from the theory of tilting modules of the quantum group $U_q(sl_2)$. We show that the simplest skein identities yield a short new proof of the existence of the Chebyshev-Frobenius homomorphism of Bonahon-Wong.

D-ideal of generic mass banana integrals in dimensional regularization
Wojciech Flieger
https://arxiv.org/abs/2508.04309 https://arxiv.org/pdf/2508.04309…

D-ideal of generic mass banana integrals in dimensional regularization
We present a set of $\ell + 3$ simple differential operators and prove that they annihilate an $\ell$-loop generic mass banana integral in dimensional regularization. We study the singular locus of the ideal generated by these operators and show that it is contained in the set of Landau singularities of the first and second type. Through the Macaulay matrix method, we calculate the corresponding holonomic rank up to $\ell = 8$, obtaining $2^{\ell +1}-1$, which agrees with the number of master i…

Chip-Firing Games on Banana Trees
Marchelle Beougher, Nila Cibu, Kexin Ding, Steven DiSilvio, Kristin Heysse, Sasha Kononova, Chan Lee, Ralph Morrison, Krish Singal
https://arxiv.org/abs/2510.03499

Chip-Firing Games on Banana Trees
We study chip-firing games on multigraphs whose underlying simple graphs are trees, paths, and stars, denoted as banana trees, paths, and stars respectively. We present a polynomial time algorithm to compute the divisorial gonality of banana paths, and give combinatorial formulas for the related invariants of scramble number and screewidth for any banana tree. Furthermore, we leverage banana paths to show that gonality can increase or decrease by an arbitrary amount upon deletion of a single ed…

Who benefits the most? Direct and indirect effects of a free cesarean section policy in Benin
Selidji Caroline Tossou
https://arxiv.org/abs/2510.03658 https://

Who benefits the most? Direct and indirect effects of a free cesarean section policy in Benin
This paper evaluates the causal effect of the access to Benin's free cesarean section policy on females and their children. I use a large sample of Demographic and Health Surveys (DHS) for West African countries and analyze how the exemption of the cesarean section user fees for females in Benin directly impacts maternal and infant mortality, family size decisions, and labor market participation. I use a Difference in Differences approach and find that having access to the free cesarean section…

Instability of the Sherman-Morrison formula and stabilization by iterative refinement
Behnam Hashemi, Yuji Nakatsukasa
https://arxiv.org/abs/2510.01696 https://

Instability of the Sherman-Morrison formula and stabilization by iterative refinement
Owing to its simplicity and efficiency, the Sherman-Morrison (SM) formula has seen widespread use across various scientific and engineering applications for solving rank-one perturbed linear systems of the form $(A+uv^T)x = b$. Although the formula dates back at least to 1944, its numerical stability properties have remained an open question and continue to be a topic of current research. We analyze the backward stability of the SM, demonstrate its instability in a scenario increasingly common …

Warum ist die #Lachmöwe ein so typischer Bewohner des Ostseeraums? 🌊 Weil die Menschen im Norden Humor haben. 😉 Mit ihrem auffälligen roten Schnabel und Beinen ist sie leicht zu erkennen. Ihr charakteristischer Ruf, der einem Lachen ähnelt, gab ihr ihren Namen. Mehr über Lachen im Artikel. 🐦✨
#Vögel

Lachmöwe (Chroicocephalus ridibundus): Typischer Bewohner des Ostseeraums
Lachmöwen im Fokus: Überleben in einer sich verändernden Welt

A dynamical formulation of multi-marginal optimal transport
Brendan Pass, Yair Shenfeld
https://arxiv.org/abs/2509.22494 https://arxiv.org/pdf/2509.22494…

A dynamical formulation of multi-marginal optimal transport
We present a primal-dual dynamical formulation of the multi-marginal optimal transport problem for (semi-)convex cost functions. Even in the two-marginal setting, this formulation applies to cost functions not covered by the classical dynamical approach of Benamou-Brenier. Our dynamical formulation yields a convex optimization problem, enabling the use of convex optimization tools to find quasi-Monge solutions of the static multi-marginal problem for translation-invariant costs. We illustrate o…

A Lightweight Crowd Model for Robot Social Navigation
Maryam Kazemi Eskeri, Thomas Wiedemann, Ville Kyrki, Dominik Baumann, Tomasz Piotr Kucner
https://arxiv.org/abs/2508.19595 …

A Lightweight Crowd Model for Robot Social Navigation
Robots operating in human-populated environments must navigate safely and efficiently while minimizing social disruption. Achieving this requires estimating crowd movement to avoid congested areas in real-time. Traditional microscopic models struggle to scale in dense crowds due to high computational cost, while existing macroscopic crowd prediction models tend to be either overly simplistic or computationally intensive. In this work, we propose a lightweight, real-time macroscopic crowd predic…

🦩 Mit bis zu zwei Metern #Flügelspannweite und auffallend roten Beinen und Schnabel ist der majestätische #Weißstorch nicht zu übersehen. Doch der #Lebensraumverlust und …

Weißstorch (Ciconia ciconia): Gefährdet durch menschliche Aktivitäten
Der Weißstorch: Wissenswertes über den majestätischen Vogel – Lebensweise, Nahrung, Brut und Schutz.

The Sunflower-Free Process
Patrick Bennett, Amanda Priestley
https://arxiv.org/abs/2509.16355 https://arxiv.org/pdf/2509.16355

The Sunflower-Free Process
An $r$-sunflower is a collection of $r$ sets such that the intersection of any two sets in the collection is identical. We analyze a random process which constructs a $w$-uniform $r$-sunflower free family starting with an empty family and at each step adding a set chosen uniformly at random from all choices that could be added without creating an $r$-sunflower with the previously chosen sets. To analyze this process, we extend results of the first author and Bohman arXiv:1308.3732v5 [math.CO], …