Tootfinder

This https://arxiv.org/abs/2404.06307 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Extremely closed subgroups and a variant on Glauberman's $Z^*$-theorem
Let $G$ be a finite group and let $H$ be a subgroup of $G$. We say that $H$ is extremely closed in $G$ if $\langle H,H^g\rangle\cap N_G(H)=H$ for all $g\in G.$ In this paper, we determine the structure of finite groups with an extremely closed abelian $p$-subgroup for some prime $p$. In particular, we show that if $G$ contains such a subgroup $H$, then $G=N_G(H)O_{p'}(G).$ This is a variant on the celebrated Glauberman's $Z^*$-Theorem.

Sublinear hitting sets for some geometric graphs
Xinbu Cheng, Zixiang Xu
https://arxiv.org/abs/2404.10379 https://arxiv.org/pdf/2404.…

Sublinear hitting sets for some geometric graphs
For an $n$-vertex graph $G$, let $h(G)$ denote the smallest size of a subset of $V(G)$ such that it intersects every maximum independent set of $G$. A conjecture posed by Bollobás, Erdős and Tuza in early 90s remains widely open, asserting that for any $n$-vertex graph $G$, if the independence number $α(G) =Ω(n) $, then $h(G) = o(n)$. In this paper, we establish the validity of this conjecture for various classes of graphs, including disk graphs, even-hole-free graphs, circle graphs, and th…

A note on weighted consecutive Davenport constant
A. Lemos, A. O. Moura, S. Ribas, A. T. Silva
https://arxiv.org/abs/2404.11312 https://

A note on weighted consecutive Davenport constant
Let $G$ be a group and $A\subseteq [1,\exp(G)-1]$. We define the constant ${\sf C}_A(G),$ which is the least positive integer $\ell$ such that every sequence over $G$ of length at least $\ell$ has an $A$-weighted consecutive product-one subsequence. In this paper, among other things, we prove that ${\sf C}_A(C_n^2)=4$ with $A=[1,n-1],$ and ${\sf C}(H\times K)=|H||K|$, where $H$ is a finite abelian group and $K$ is a metacyclic group.

This https://arxiv.org/abs/2307.01960 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

A Serre spectral sequence for the moduli space of tropical curves
We construct, for all $g\geq 2$ and $n\geq 0$, a spectral sequence of rational $S_n$-representations which computes the $S_n$-equivariant reduced rational cohomology of the tropical moduli spaces of curves $Δ_{g,n}$ in terms of compactly supported cohomology groups of configuration spaces of $n$ points on graphs of genus $g$. Using the canonical $S_n$-equivariant isomorphisms $\widetilde{H}^{i-1}(Δ_{g,n};\mathbb{Q}) \cong W_0 H^i_c(\mathcal{M}_{g,n};\mathbb{Q})$, we calculate the weight $0$, …

Hej Danish bubble, is there any official site or source to find out which type of electricity an el provider (e.g. Norlys) is providing or which electricity mix this company is buying from the market?
Maybe @… or @… kn…

Discovery of the optical and radio counterpart to the fast X-ray transient EP240315a
J. H. Gillanders, L. Rhodes, S. Srivastav, F. Carotenuto, J. Bright, M. E. Huber, H. F. Stevance, S. J. Smartt, K. C. Chambers, T. -W. Chen, R. Fender, A. Andersson, A. J. Cooper, P. G. Jonker, F. J. Cowie, T. deBoer, N. Erasmus, M. D. Fulton, H. Gao, J. Herman, C. -C. Lin, T. Lowe, E. A. Magnier, H. -Y. Miao, P. Minguez, T. Moore, C. -C. Ngeow, M. Nicholl, Y. -C. Pan, G. Pignata, A. Rest, X. Sheng, I.…

Discovery of the optical and radio counterpart to the fast X-ray transient EP240315a
Fast X-ray Transients (FXTs) are extragalactic bursts of soft X-rays first identified >10 years ago. Since then, nearly 40 events have been discovered, although almost all of these have been recovered from archival Chandra and XMM-Newton data. To date, optical sky surveys and follow-up searches have not revealed any multi-wavelength counterparts. The Einstein Probe, launched in January 2024, has started surveying the sky in the soft X-ray regime (0.5-4 keV) and will rapidly increase the sample …

This https://arxiv.org/abs/1904.12500 has been replaced.
link: https://scholar.google.com/scholar?q=a

Composing dynamic programming tree-decomposition-based algorithms
Given two integers $\ell$ and $p$ as well as $\ell$ graph classes $\mathcal{H}_1,\ldots,\mathcal{H}_\ell$, the problems $\mathsf{GraphPart}(\mathcal{H}_1, \ldots, \mathcal{H}_\ell,p)$, \break $\mathsf{VertPart}(\mathcal{H}_1, \ldots, \mathcal{H}_\ell)$, and $\mathsf{EdgePart}(\mathcal{H}_1, \ldots, \mathcal{H}_\ell)$ ask, given graph $G$ as input, whether $V(G)$, $V(G)$, $E(G)$ respectively can be partitioned into $\ell$ sets $S_1, \ldots, S_\ell$ such that, for each $i$ between $1$ and $\ell$,…

Forbidden subgraphs generating a finite set of graphs with minimum degree three and large girth
Yoshimi Egawa, Michitaka Furuya
https://arxiv.org/abs/2404.10996

Forbidden subgraphs generating a finite set of graphs with minimum degree three and large girth
For a family $\mathcal{H}$ of graphs, a graph $G$ is said to be {\it $\mathcal{H}$-free} if $G$ contains no member of $\mathcal{H}$ as an induced subgraph. We let $\tilde{\mathcal{G}}_{3}(\mathcal{H})$ denote the family of connected $\mathcal{H}$-free graphs having minimum degree at least $3$. In this paper, we characterize the non-caterpillar trees $T$ having diameter at least $7$ such that $\tilde{\mathcal{G}}_{3}(\{C_{3},C_{4},T\})$ is a finite family, where $C_{n}$ is a cycle of order $n$.

Deep JWST/NIRCam imaging of Supernova 1987A
Mikako Matsuura, M. Boyer, Richard G. Arendt, J. Larsson, C. Fransson, A. Rest, A. P. Ravi, S. Park, P. Cigan, T. Temim, E. Dwek, M. J. Barlow, P. Bouchet, G. Clayton, R. Chevalier, J. Danziger, J. De Buizer, I. De Looze, G. De Marchi, O. Fox, C. Gall, R. D. Gehrz, H. L. Gomez, R. Indebetouw, T. Kangas, F. Kirchschlager, R. Kirshner, P. Lundqvist, J. M. Marcaide, I. Mart\'i-Vidal, M. Meixner, D. Milisavljevic, S. Orlando, M. Otsuka, F. Pr…

Deep JWST/NIRCam imaging of Supernova 1987A
JWST/NIRCam obtained high angular-resolution (0.05-0.1''), deep near-infrared 1--5 micron imaging of Supernova (SN) 1987A taken 35 years after the explosion. In the NIRCam images, we identify: 1) faint H2 crescents, which are emissions located between the ejecta and the equatorial ring, 2) a bar, which is a substructure of the ejecta, and 3) the bright 3-5 micron continuum emission exterior to the equatorial ring. The emission of the remnant in the NIRCam 1-2.3 micron images is mostly due to li…

Solution to the iterative differential equation $-\gamma g' = g^{-1}$
Roland Miyamoto
https://arxiv.org/abs/2404.11455 https://ar…

Solution to the iterative differential equation $-γg' = g^{-1}$
Using a Picard-like operator $T$, we prove that the iterative differential equation $-γg' = g^{-1}$ with parameter $γ>0$ has a solution $g=h\colon[0,1]\to[0,1]$ for only one value $γ=κ\approx0.278877$, and that this solution $h$ is unique. As an even stronger result, we exhibit $h$ as the global limit of the operator $T$.

Magnetic structure and magnetoelectric coupling in antiferromagnet Co5(TeO3)4Cl2
B. Yu, L. Huang, J. S. Li, L. Lin, V. Ovidiu Garlea, Q. Zhang, T. Zou, J. C. Zhang, J. Peng, Y. S. Tang, G. Z. Zhou, J. H. Zhang, S. H. Zheng, M. F. Liu, Z. B. Yan, X. H. Zhou, S. Dong, J. G. Wan, J. -M. Liu
https://arxiv.org/abs/2405.09776

On Homomorphism Indistinguishability and Hypertree Depth
Benjamin Scheidt
https://arxiv.org/abs/2404.10637 https://arxiv.org/pdf/2404…

On Homomorphism Indistinguishability and Hypertree Depth
$GC^k$ is a logic introduced by Scheidt and Schweikardt (2023) to express properties of hypergraphs. It is similar to first-order logic with counting quantifiers ($C$) adapted to the hypergraph setting. It has distinct sets of variables for vertices and for hyperedges and requires vertex variables to be guarded by hyperedge variables on every quantification. We prove that two hypergraphs $G$, $H$ satisfy the same sentences in the logic $GC^k$ with guard depth at most $k$ if, and only if, they…

Stability of transversal Hamilton cycles and paths
Yangyang Cheng, Katherine Staden
https://arxiv.org/abs/2403.09913 https://arxiv.or…

Stability of transversal Hamilton cycles and paths
Given graphs $G_1,\ldots,G_s$ all on a common vertex set and a graph $H$ with $e(H) = s$, a copy of $H$ is \emph{transversal} or \emph{rainbow} if it contains one edge from each $G_i$. We establish a stability result for transversal Hamilton cycles: the minimum degree required to guarantee a transversal Hamilton cycle can be lowered as long as the graph collection $G_1,\ldots,G_n$ is far in edit distance from several extremal cases. We obtain an analogous result for Hamilton paths. The proof is…

Probing Weyl-type $f(Q, T)$ gravity: Cosmological implications and constraints
Alnadhief H. A. Alfedeel, M. Koussour, N. Myrzakulov
https://arxiv.org/abs/2403.09916

Probing Weyl-type $f(Q, T)$ gravity: Cosmological implications and constraints
In this paper, we investigate the cosmological implications and constraints of Weyl-type $f(Q, T)$ gravity. This theory introduces a coupling between the non-metricity $Q$ and the trace $T$ of the energy-momentum tensor, using the principles of proper Weyl geometry. In this geometry, the scalar non-metricity $Q$, which characterizes the deviations from Riemannian geometry, is expressed in its standard Weyl form $\nabla _{μ}g_{αβ}=-w_{μ}g_{αβ}$ and is determined by a vector field $w_{μ}$.…

This https://arxiv.org/abs/2402.16317 has been replaced.
initial toot: https://mastoxiv.page/@arX…

Effects of group size and noise on cooperation in population evolution of dynamic groups
In a large population, the agents temporally form group of the Public Goods Game (PGG) one after another, and size of one group is randomly distributed at $g\in [g_l,g_h]$. Players in it have two strategies to be chosen to cooperate, or to defect for playing the PGG. Based on this structure we investigate the evolution of cooperation in PGG as a function of the noise level underlying strategy adoptions with the group size distribution. In the process of the evolution, the payoffs of cooperators…

This https://arxiv.org/abs/2303.07157 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Computing equivariant matrices on homogeneous spaces for Geometric Deep Learning and Automorphic Lie Algebras
We develop an elementary method to compute spaces of equivariant maps from a homogeneous space $G/H$ of a Lie group $G$ to a module of this group. The Lie group is not required to be compact. More generally, we study spaces of invariant sections in homogeneous vector bundles, and take a special interest in the case where the fibres are algebras. These latter cases have a natural global algebra structure. We classify these automorphic algebras for the case where the homogeneous space has compact…

This https://arxiv.org/abs/2203.01140 has been replaced.
link: https://scholar.google.com/scholar?q=a

Finite quotients of 3-manifold groups
For $G$ and $H_1,\dots, H_n$ finite groups, does there exist a $3$-manifold group with $G$ as a quotient but no $H_i$ as a quotient? We answer all such questions in terms of the group cohomology of finite groups. We prove non-existence with topological results generalizing the theory of semicharacteristics. To prove existence of 3-manifolds with certain finite quotients but not others, we use a probabilistic method, by first proving a formula for the distribution of the (profinite completion of…

Pls note this coincides with the unexpected passage into law of H.R.815, Division H, Section 2, paragraph (g), sub-paragraph (3)(B) - otherwise known as the TikTok ban, but actually quite possibly applicable to Telegram too.
See: https://www.thegist.ie/the-gist-banning-tiktok/
https://mas.to/@bascule/112430529016726544

This https://arxiv.org/abs/2403.07659 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

The power operation in the Galois cohomology of a reductive group over a number field
For a connected reductive group $G$ over a local or global field $K$, we define a *diamond* (or *power*) operation $$(ξ, n)\mapsto ξ^{\Diamond n}\, \colon\ H^1(K,G)\times {\mathbb Z}\to H^1(K,G)$$ of raising to power $n$ in the Galois cohomology pointed set (this operation is new when $K$ is a number field). We show that this operation has many functorial properties. When $G$ is a torus, the ponted set $H^1(K,G)$ has a natural group structure, and our new operation coincides with the usual po…

This https://arxiv.org/abs/2211.08589 has been replaced.
link: https://scholar.google.com/scholar?q=a

The rainbow saturation number is linear
Given a graph $H$, we say that an edge-coloured graph $G$ is $H$-rainbow saturated if it does not contain a rainbow copy of $H$, but the addition of any non-edge in any colour creates a rainbow copy of $H$. The rainbow saturation number $\text{rsat}(n,H)$ is the minimum number of edges among all $H$-rainbow saturated edge-coloured graphs on $n$ vertices. We prove that for any non-empty graph $H$, the rainbow saturation number is linear in $n$, thus proving a conjecture of Girão, Lewis, and Pop…

This https://arxiv.org/abs/2306.14279 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Local cohomology of modular invariant rings
For $K$ a field, consider a finite subgroup $G$ of $\operatorname{GL}_n(K)$ with its natural action on the polynomial ring $R:=K[x_1,\dots,x_n]$. Let $\mathfrak{n}$ denote the homogeneous maximal ideal of the ring of invariants $R^G$. We study how the local cohomology module $H^n_{\mathfrak{n}}(R^G)$ compares with $H^n_{\mathfrak{n}}(R)^G$. Various results on the $a$-invariant and on the Hilbert series of $H^n_\mathfrak{n}(R^G)$ are obtained as a consequence.

On the covariant coefficients of geodesic sprays on Finsler manifolds
S. G. Elgendi, A. Soleiman, Nabil L. Youssef
https://arxiv.org/abs/2404.07995 https:/…

On the covariant coefficients of geodesic sprays on Finsler manifolds
For a Finsler metric $F$, we introduce the notion of $F$-covariant coefficients $H_i$ of the geodesic spray of $F$ (Def. 3.1). We study some geometric consequences concerning the objects $H_i$. If the $F$-covariant coefficients $H_i$ are written in the form $H_i={\dot{\partial}}_iH$, for some smooth function $H$ on ${\mathcal T\hspace{-1pt}M}$, positively 3-homogeneous in y, then $H$ is called spray scalar or simply $S$-scalar. We prove that if the $S$-scalar exists, then it is of the form $H=\…

Constructing heat kernels on infinite graphs
Jay Jorgenson, Anders Karlsson, Lejla Smajlovi\'c
https://arxiv.org/abs/2404.11535 https://

Constructing heat kernels on infinite graphs
Let $G$ be an infinite, edge- and vertex-weighted graph with certain reasonable restrictions. We construct the heat kernel of the associated Laplacian using an adaptation of the parametrix approach due to Minakshisundaram-Pleijel in the setting of Riemannian geometry. This is partly motivated by the wish to relate the heat kernels of a graph and a subgraph, or of a domain and a discretization of it. As an application, assuming that the graph is locally finite, we express the heat kernel $H_G(x,…

Robust and tractable multidimensional exponential analysis
H. N. Mhaskar, S. Kitimoon, Raghu G. Raj
https://arxiv.org/abs/2404.11004 https://

Robust and tractable multidimensional exponential analysis
Motivated by a number of applications in signal processing, we study the following question. Given samples of a multidimensional signal of the form \begin{align*} f(\bs\ell)=\sum_{k=1}^K a_k\exp(-i\langle \bs\ell, \w_k\rangle), \\ \w_1,\cdots,\w_k\in\mathbb{R}^q, \ \bs\ell\in \ZZ^q, \ |\bs\ell|

Safety-Critical Control for Autonomous Systems: Control Barrier Functions via Reduced-Order Models
Max H. Cohen, Tamas G. Molnar, Aaron D. Ames
https://arxiv.org/abs/2403.09865

Safety-Critical Control for Autonomous Systems: Control Barrier Functions via Reduced-Order Models
Modern autonomous systems, such as flying, legged, and wheeled robots, are generally characterized by high-dimensional nonlinear dynamics, which presents challenges for model-based safety-critical control design. Motivated by the success of reduced-order models in robotics, this paper presents a tutorial on constructive safety-critical control via reduced-order models and control barrier functions (CBFs). To this end, we provide a unified formulation of techniques in the literature that share a…

Looking through Academics of Mastodon https://nathanlesage.github.io/academics-on-mastodon/, but frustrating, as many accounts were set up in 2022 and haven't posted for a year or more. Has anyone thought about or attempted a "live" directory with e.g. number of posts / week, last posted dates?
cc @…

GHOST Commissioning Science Results III: Characterizing an iron-poor damped Lyman $\alpha$ system
Trystyn A. M. Berg, Christian R. Hayes, Stefano Cristiani, Alan McConnachie, Federico Sestito, Chris Simpson, Fletcher Waller, Timothy Chin, Adam Densmore, Ruben J. Diaz, Michael L. Edgar, Javier Fuentes Lettura, Manuel G\'omez-Jim\'enez, Venu M. Kalari, Jon Lawrence, Steven Margheim, John Pazder, Roque Ruiz-Carmona, Ricardo Salinas, Karleyne M. G. Silva, Katherine Silversides, Kim…

GHOST Commissioning Science Results III: Characterizing an iron-poor damped Lyman $α$ system
The Gemini High-resolution Optical SpecTrograph (GHOST) is a new echelle spectrograph available on the Gemini-South telescope as of Semester 2024A. We present the first high resolution spectrum of the quasar J1449-1227 (redshift z_em=3.27) using data taken during the commissioning of GHOST. The observed quasar hosts an intervening iron-poor ([Fe/H] = -2.5) damped Lyman alpha (DLA) system at redshift z=2.904. Taking advantage of the high spectral resolving power of GHOST (R~55000), we are able t…

This https://arxiv.org/abs/2211.08589 has been replaced.
link: https://scholar.google.com/scholar?q=a

The rainbow saturation number is linear
Given a graph $H$, we say that an edge-coloured graph $G$ is $H$-rainbow saturated if it does not contain a rainbow copy of $H$, but the addition of any non-edge in any colour creates a rainbow copy of $H$. The rainbow saturation number $\text{rsat}(n,H)$ is the minimum number of edges among all $H$-rainbow saturated edge-coloured graphs on $n$ vertices. We prove that for any non-empty graph $H$, the rainbow saturation number is linear in $n$, thus proving a conjecture of Girão, Lewis, and Pop…

Magnetic structure and magnetoelectric coupling in antiferromagnet Co5(TeO3)4Cl2
B. Yu, L. Huang, J. S. Li, L. Lin, V. Ovidiu Garlea, Q. Zhang, T. Zou, J. C. Zhang, J. Peng, Y. S. Tang, G. Z. Zhou, J. H. Zhang, S. H. Zheng, M. F. Liu, Z. B. Yan, X. H. Zhou, S. Dong, J. G. Wan, J. -M. Liu
https://arxiv.org/abs/2405.09776

A magnetic massive star has experienced a stellar merger
A. J. Frost, H. Sana, L. Mahy, G. Wade, J. Barron, J. -B. Le Bouquin, A. M\'erand, F. R. N. Schneider, T. Shenar, R. H. Barb\'a, D. M. Bowman, M. Fabry, A. Farhang, P. Marchant, N. I. Morrell, J. V. Smoker
https://arxiv.org/abs/2404.10167

A magnetic massive star has experienced a stellar merger
Massive stars (those larger than 8 solar masses at formation) have radiative envelopes that cannot sustain a dynamo, the mechanism that produces magnetic fields in lower-mass stars. Despite this, approximately 7\% of massive stars have observed magnetic fields, the origin of which is debated. We used multi-epoch interferometric and spectroscopic observations to characterize HD 148937, a binary system of two massive stars. We found that only one star is magnetic and that it appears younger than …

First evidence of a connection between cluster-scale diffuse radio emission in cool-core galaxy clusters and sloshing features
N. Biava, A. Bonafede, F. Gastaldello, A. Botteon, M. Brienza, T. W. Shimwell, G. Brunetti, L. Bruno, K. Rajpurohit, C. J. Riseley, R. J. van Weeren, M. Rossetti, R. Cassano, F. De Gasperin, A. Drabent, H. J. A. Rottgering, A. C. Edge, C. Tasse

First evidence of a connection between cluster-scale diffuse radio emission in cool-core galaxy clusters and sloshing features
Radio observations of a few cool-core galaxy clusters have revealed the presence of diffuse emission on cluster scales, similar to what was found in merging clusters in the form of radio halos. These sources might suggest that a minor merger, while not sufficiently energetic to disrupt the cool core, could still trigger particle acceleration in the intracluster medium on scales of hundreds of kpc. We observed with LOFAR at 144 MHz a sample of twelve cool-core galaxy clusters presenting some lev…

This https://arxiv.org/abs/2203.12021 has been replaced.
link: https://scholar.google.com/scholar?q=a

On groups with large verbal quotients
Let $w=w(x_1,...,x_n)$ be a word, i.e. an element of the free group $F = \langle x_1,...,x_n \rangle$. The verbal subgroup $w(G)$ of a group $G$ is the subgroup generated by the set $\{ w(x_1,...,x_n) : x_1,...,x_n \in G \}$ of all $w$-values in $G$. Following J. González-Sánchez and B. Klopsch, a group $G$ is $w$-maximal if $|H:w(H)| < |G:w(G)|$ for every $H

A newly developed multi-kilo-channel high-speed and precision waveform digitization system for neutrino experiments
H. Yang, T. Xue, L. Jiang, C. Xu, Q. Pan, B. Liang, G. Gong, B. Xu, Z. Wang, S. Chen, Y. Liu, J. Li
https://arxiv.org/abs/2404.10373

A newly developed multi-kilo-channel high-speed and precision waveform digitization system for neutrino experiments
The Jinping Neutrino Experiment(JNE), conducted within the China Jinping Underground Laboratory, aims to detect and analyze of solar neutrinos, geo-neutrinos, and supernova neutrinos. A one-ton prototype will soon be in commision with an upgrade from 30 channels to 60 channels, which will increase the data bandwidth by one to two orders of magnitude and exceed the capacity of the current CAEN DAQ system. Additionally, enhancing the performance and flexibility of JNE DAQ system is crucial. This …

Probing Weyl-type $f(Q, T)$ gravity: Cosmological implications and constraints
Alnadhief H. A. Alfedeel, M. Koussour, N. Myrzakulov
https://arxiv.org/abs/2403.09916

Probing Weyl-type $f(Q, T)$ gravity: Cosmological implications and constraints
In this paper, we investigate the cosmological implications and constraints of Weyl-type $f(Q, T)$ gravity. This theory introduces a coupling between the non-metricity $Q$ and the trace $T$ of the energy-momentum tensor, using the principles of proper Weyl geometry. In this geometry, the scalar non-metricity $Q$, which characterizes the deviations from Riemannian geometry, is expressed in its standard Weyl form $\nabla _{μ}g_{αβ}=-w_{μ}g_{αβ}$ and is determined by a vector field $w_{μ}$.…

This https://arxiv.org/abs/2209.03402 has been replaced.
link: https://scholar.google.com/scholar?q=a

Counting Subgraphs in Somewhere Dense Graphs
We study the problems of counting copies and induced copies of a small pattern graph $H$ in a large host graph $G$. Recent work fully classified the complexity of those problems according to structural restrictions on the patterns $H$. In this work, we address the more challenging task of analysing the complexity for restricted patterns and restricted hosts. Specifically we ask which families of allowed patterns and hosts imply fixed-parameter tractability, i.e., the existence of an algorithm r…

Inclination instability of circumbinary planets
Stephen H. Lubow, Anna C. Childs, Rebecca G. Martin
https://arxiv.org/abs/2404.10080 https://

Inclination instability of circumbinary planets
We analyze a tilt instability of the orbit of an outer planet in a two planet circumbinary system that we recently reported. The binary is on an eccentric orbit and the inner circumbinary planet is on a circular polar orbit that causes the the binary to undergo apsidal precession. The outer circumbinary planet is initially on a circular or eccentric orbit that is coplanar with respect to the binary. We apply a Hamiltonian in quadrupole order of the binary potential to show that the tilt instabi…

Nach der zweiten Runde, ist erstmal kurz Pause. Die Spieler:innen können sich beim Mittagessen stärken und um 14:00 Uhr starten sie in die dritte Runde.
Ergebnisse der zweiten Runde:
https://www.deutsche-schachjugend.de/2024/dsm-wk-g/runde/2/

This https://arxiv.org/abs/2402.16317 has been replaced.
initial toot: https://mastoxiv.page/@arX…

Effects of group size and noise on cooperation in population evolution of dynamic groups
In a large population, the agents temporally form group of the Public Goods Game (PGG) one after another, and size of one group is randomly distributed at $g\in [g_l,g_h]$. Players in it have two strategies to be chosen to cooperate, or to defect for playing the PGG. Based on this structure we investigate the evolution of cooperation in PGG as a function of the noise level underlying strategy adoptions with the group size distribution. In the process of the evolution, the payoffs of cooperators…

https://www.theonion.com/17-days-in-incubator-longest-time-premature-baby-will-g-1851456014
h/t @…

17 Days In Incubator Longest Time Premature Baby Will Go Without Being Exposed To Advertising
NEW YORK—Describing the newborn’s stint in a neonatal intensive care unit as a brief, blissful period during which she was still beyond the reach of marketers, sources confirmed Monday that her 17 days in an incubator would be the longest period of her life in which premature baby Rosalyn Williams was not exposed to…

Spatial characterization of debris ejection from the interaction of a tightly focused PW-laser pulse with metal targets
I. -M. Vladisavlevici, C. Vlachos, J. -L. Dubois, A. Huerta, S. Agarwal, H. Ahmed, J. I. Api\~naniz, M. Cernaianu, M. Gugiu, M. Krupka, R. Lera, A. Morabito, D. Sangwan, D. Ursescu, A. Curcio, N. Fefeu, J. A. P\'erez-Hern\'andez, T. Vacek, P. Vicente, N. Woolsey, G. Gatti, M. D. Rodr\'iguez-Fr\'ias, J. J. Santos, P. W. Bradford, M. Ehret

Spatial characterization of debris ejection from the interaction of a tightly focused PW-laser pulse with metal targets
We present a novel scheme for rapid quantitative analysis of debris generated during experiments with solid targets following relativistic laser-plasma interaction at high-power laser facilities. Experimental data indicates that predictions by available modelling for non-mass-limited targets are reasonable, with debris on the order of hundreds ug-per-shot. We detect for the first time that several % of the debris is ejected directional following the target normal (rear- and interaction side); a…

@… Whether it’s “sufficient” depends on what you want. You don’t need to assign a country ID or, for that matter, any ID. You could indicate a region, or you could, e.g., just give longitude and latitude and leave any further interpretation for later. There’s no “right” way. You should just be consistent.
@…

@… Whether it’s “sufficient” depends on what you want. You don’t need to assign a country ID or, for that matter, any ID. You could indicate a region, or you could, e.g., just give longitude and latitude and leave any further interpretation for later. There’s no “right” way. You should just be consistent.
@…

New @… on the privacy nightmare that is your car; if only we had some kind of data protection here in the US to get a handle on the wild west of data brokers like LexisNexus who supply insurers with our driving telematics. #GiftLink

Automakers Are Sharing Consumers’ Driving Behavior With Insurance Companies
LexisNexis, which generates consumer risk profiles for the insurers, knew about every trip G.M. drivers had taken in their cars, including when they sped, braked too hard or accelerated rapidly.

This https://arxiv.org/abs/2308.04962 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Computing Galois cohomology of a real linear algebraic group
Let G be a linear algebraic group, not necessarily connected or reductive, over the field of real numbers R. We describe a method, implemented on computer, to find the first Galois cohomology set H^1(R,G). The output is a list of 1-cocycles in G. Moreover, we have an implemented algorithm that, given a 1-cocycle z in Z^1(R,G), finds the cocycle in the computed list to which z is equivalent, together with an element of G(C) realizing the equivalence.

Pls note this coincides with the unexpected passage into law of H.R.815, Division H, Section 2, paragraph (g), sub-paragraph (3)(B) - otherwise known as the TikTok ban, but actually quite possibly applicable to Telegram too.
See: https://www.thegist.ie/the-gist-banning-tiktok/
https://mas.to/@bascule/112430529016726544

Does anyone use the "g" letter combination keyboard shortcuts? I'm wondering where its origin are from. Also made a quick comparison table of them for Pinafore, Mastodon, X and Elk (Phanpy doesn't support them).
#KeyboardShortcuts #WebApps

How do we create spaces where people don't feel constantly evaluated and scored?
@… pointed out an important aspect that isn't often discussed: as Safety-II recommends, focus on the successes rather than on the failures.
https://hachyderm.io/@recursive/112260749356751561
That doesn't mean only talking about what went well, rather that "what could be better" focuses on how to create success instead of naming mistakes. E.g., instead of "you missed this deadline", maybe "please make sure to call out things that aren't on-track and when priorities change"

This https://arxiv.org/abs/2107.05772 has been replaced.
link: https://scholar.google.com/scholar?q=a

On λ-backbone coloring of cliques with tree backbones in linear time
A $λ$-backbone coloring of a graph $G$ with its subgraph (also called a backbone) $H$ is a function $c \colon V(G) \rightarrow \{1,\dots, k\}$ ensuring that $c$ is a proper coloring of $G$ and for each $\{u,v\} \in E(H)$ it holds that $|c(u) - c(v)| \ge λ$. In this paper we propose a way to color cliques with tree and forest backbones in linear time that the largest color does not exceed $\max\{n, 2 λ\} + Δ(H)^2 \lceil\log{n} \rceil$. This result improves on the previously existin…

Noncommutative domains, universal operator models, and operator algebras, II
Gelu Popescu
https://arxiv.org/abs/2404.09073 https://ar…

Noncommutative domains, universal operator models, and operator algebras, II
In a recent paper, we introduced and studied the class of admissible noncommutative domains $D_{g^{-1}}(H)$ in $B(H)^n$ associated with admissible free holomorphic functions $g$ in noncommutative indeterminates $Z_1,\ldots, Z_n$. Each such a domain admits a universal model ${\bf W}:=(W_1,\ldots, W_n)$ of weighted left creation operators acting on the full Fock space with $n$ generators. In the present paper, we continue the study of these domains and their universal models in connection with th…

Improving pulsar timing precision through superior Time-of-Arrival creation
J. Wang, J. P. W. Verbiest, G. M. Shaifullah, I. Cognard, L. Guillemot, G. H. Janssen, M. B. Mickaliger, A. Possenti, G. Theureau
https://arxiv.org/abs/2405.08629

@… Maybe this is an opportunity to work on your empathy.
See e.g. https://www.watson.de/leben…

Spherical amoebae and a spherical logarithm map
Victor Batyrev, Megumi Harada, Johannes Hofscheier, Kiumars Kaveh
https://arxiv.org/abs/2403.09091 https://…

Spherical amoebae and a spherical logarithm map
Let $G$ be a connected reductive algebraic group over $\mathbb{C}$ with a maximal compact subgroup $K$. Let $G/H$ be a (quasi-affine) spherical homogeneous space. In the first part of the paper, following Akhiezer's definition of spherical functions, we introduce a $K$-invariant map $sLog_{Γ, t}: G/H \to \mathbb{R}^s$ which depends on a choice of a finite set $Γ$ of dominant weights and $s = |Γ|$. We call $sLog_{Γ, t}$ a spherical logarithm map. We show that when $Γ$ generates th…

Perovskite Phase Heterojunction Solar Cells
Ran Ji, Zongbao Zhang, Yvonne J. Hofstetter, Robin Buschbeck, Christian H\"anisch, Fabian Paulus, Yana Vaynzof
https://arxiv.org/abs/2404.11264

Perovskite Phase Heterojunction Solar Cells
Modern photovoltaic devices are often based on a heterojunction structure where two components with different optoelectronic properties are interfaced. The properties of each side of the junction can be tuned by either utilizing different materials (e.g. donor/acceptor) or doping (e.g. PN Si junction) or even varying their dimensionality (e.g. 3D/2D). In this work we demonstrate the concept of phase heterojunction (PHJ) solar cells by utilizing two polymorphs of the same material. We demonstrat…

This https://arxiv.org/abs/2401.14062 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Minimal doubling for small subsets in compact Lie groups
We prove a sharp bound for the minimal doubling of a small measurable subset of a compact connected Lie group. Namely, let $G$ be a compact connected Lie group of dimension $d_G$, we show that for for all measurable subsets $A$, we have $$μ_G(A^2) \geq \left(2^{d_G-d_H} - Cμ_G(A)^{\frac{2}{d_G-d_H}}\right)μ_G(A)$$ where $d_H$ is the maximal dimension of a proper closed subgroup $H$ and $C > 0$ is a dimensional constant. This settles a conjecture of Breuillard and Green, and recovers and impr…

Probing particle acceleration in Abell 2256: from to 16 MHz to gamma rays
E. Osinga, R. J. van Weeren, G. Brunetti, R. Adam, K. Rajpurohit, A. Botteon, J. R. Callingham, V. Cuciti, F. de Gasperin, G. K. Miley, H. J. A. R\"ottgering, T. W. Shimwell
https://arxiv.org/abs/2405.09384

This https://arxiv.org/abs/2303.03552 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Homological representations of low genus mapping class groups
Given a finite group $G$ acting on a surface $S$, the centralizer of G in the mapping class group $\textrm{Mod}(S)$ has a natural representation given by its action on the homology $H_1(S; \mathbb{Q})$. We consider the question of whether this representation has arithmetic image. Several authors have given positive and negative answers to this question. We give a complete answer when S has genus at most 3.

The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
V. Pelgrims, N. Mandarakas, R. Skalidis, K. Tassis, G. V. Panopoulou, V. Pavlidou, D. Blinov, S. Kiehlmann, S. E. Clark, B. S. Hensley, S. Romanopoulos, A. Basyrov, H. K. Eriksen, M. Falalaki, T. Ghosh, E. Gjerl{\o}w, J. A. Kypriotakis, S. Maharana, A. Papadaki, T. J. Pearson, S. B. Potter, A. N. Ramaprakash, A. C. S. Readhead, I. K. Wehus

The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium
We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimeter at Skinakas Observatory to conduct a survey of starlight polarization in a region of the sky of 4 square degrees. We propose a Bayesian method to decompose the stellar-polarization source field along the distance to invert the 3D volume occupied by the observed stars. We used it to obtain the first 3D map of the du…

Astrometric detection of a Neptune-mass candidate planet in the nearest M-dwarf binary system GJ65 with VLTI/GRAVITY
GRAVITY Collaboration, R. Abuter, A. Amorim, M. Benisty, J-P. Berger, H. Bonnet, G. Bourdarot, P. Bourget, W. Brandner, Y. Cl\'enet, R. Davies, F. Delplancke-Str\"obele, R. Dembet, A. Drescher, A. Eckart, F. Eisenhauer, H. Feuchtgruber, G. Finger, N. M. F\"orster-Schreiber, P. Garcia, R. Garcia-Lopez, F. Gao, E. Gendron, R. Genzel, S. Gillessen, M. Hartl, X…

Astrometric detection of a Neptune-mass candidate planet in the nearest M-dwarf binary system GJ65 with VLTI/GRAVITY
The detection of low-mass planets orbiting the nearest stars is a central stake of exoplanetary science, as they can be directly characterized much more easily than their distant counterparts. Here, we present the results of our long-term astrometric observations of the nearest binary M-dwarf Gliese 65 AB (GJ65), located at a distance of only 2.67 pc. We monitored the relative astrometry of the two components from 2016 to 2023 with the VLTI/GRAVITY interferometric instrument. We derived highly …

The power operation in the Galois cohomology of a reductive group over a number field
Mikhail Borovoi, Zinovy Reichstein
https://arxiv.org/abs/2403.07659 h…

The power operation in the Galois cohomology of a reductive group over a number field
For a connected reductive group $G$ over a local or global field $K$, we define a *diamond* (or *power*) operation $$(ξ, n)\mapsto ξ^{\Diamond n}\, \colon\ H^1(K,G)\times {\mathbb Z}\to H^1(K,G)$$ of raising to power $n$ in the Galois cohomology pointed set (this operation is new when $K$ is a number field). We show that this operation has many functorial properties. When $G$ is a torus, the ponted set $H^1(K,G)$ has a natural group structure, and our new operation coincides with the usual po…

This https://arxiv.org/abs/2205.06020 has been replaced.
link: https://scholar.google.com/scholar?q=a

Hurwitz moduli varieties parameterizing Galois covers of an algebraic curve
Given a smooth, projective curve $Y$, a finite group $G$ and a positive integer $n$ we study smooth, proper families $X\to Y\times S\to S$ of Galois covers of $Y$ with Galois group isomorphic to $G$ branched in $n$ points, parameterized by algebraic varieties $S$. When $G$ is with trivial center we prove that the Hurwitz space $H^G_n(Y)$ is a fine moduli variety for this moduli problem and construct explicitly the universal family. For arbitrary $G$ we prove that $H^G_n(Y)$ is a coarse moduli v…

This https://arxiv.org/abs/2403.05284 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_grqc_…

Gravity as a topological gauge theory
We describe a topological gauge theory with underlying Cartan geometry $G/H$ and principal $H$-bundle. The topological action is constructed as a linear combination of the Euler and Pontrjagin numbers coming from entries of the curvature $\barΩ$ of a Cartan connection. As an example we show that for respectively $G= \left\{ \begin{array}{ll} SO(4,1) \text{ for } Λ_0 > 0 SO(3,2) \text{ for } Λ_0 < 0 \end{array} \right.$ and $H=SO(3,1)$ a very particular linear combination yiel…

Improved Exponent for Marton's Conjecture in $\mathbb{F}_2^n$
Jyun-Jie Liao
https://arxiv.org/abs/2404.09639 https://arxiv.org/pd…

Improved Exponent for Marton's Conjecture in $\mathbb{F}_2^n$
A conjecture of Marton, widely known as the polynomial Freiman-Ruzsa conjecture, was recently proved by Gowers, Green, Manners and Tao for any bounded-torsion Abelian group $G$. In this paper we show a few simple modifications that improve their bound in $G=\mathbb{F}_2^n$. Specifically, for $G=\mathbb{F}_2^n$, they proved that any set $A\subseteq G$ with $|A+A|\le K|A|$ can be covered by at most $2K^C$ cosets of a subgroup $H$ of $G$ of cardinality at most $|A|$, …

Extremely closed subgroups and a variant on Glauberman's $Z^*$-theorem
Hung P. Tong-Viet
https://arxiv.org/abs/2404.06307 https://

Extremely closed subgroups and a variant on Glauberman's $Z^*$-theorem
Let $G$ be a finite group and let $H$ be a subgroup of $G$. We say that $H$ is extremely closed in $G$ if $\langle H,H^g\rangle\cap N_G(H)=H$ for all $g\in G.$ In this paper, we determine the structure of finite groups with an extremely closed abelian $p$-subgroup for some prime $p$. In particular, we show that if $G$ contains such a subgroup $H$, then $G=N_G(H)O_{p'}(G).$ This is a variant on the celebrated Glauberman's $Z^*$-Theorem.

Role of nonlocal heat transport on the laser ablative Rayleigh-Taylor instability
Z. H. Chen, X. H. Yang, G. B. Zhang, Y. Y. Ma, R. Yan, H. Xu, Z. M. Sheng, F. Q. Shao, J. Zhang
https://arxiv.org/abs/2404.08216

Role of nonlocal heat transport on the laser ablative Rayleigh-Taylor instability
Ablative Rayleigh-Taylor instability (ARTI) and nonlocal heat transport are the critical problems in laser-driven inertial confinement fusion, while their coupling with each other is not completely understood yet. Here the ARTI in the presence of nonlocal heat transport is studied self-consistently for the first time theoretically and by using radiation hydrodynamic simulations. It is found that the nonlocal heat flux generated by the hot electron transport tends to attenuate the growth of inst…

The Gaia-ESO Survey: Calibrating the lithium-age relation with open clusters and associations. II. Expanded cluster sample and final membership selection
M. L. Guti\'errez Albarr\'an, D. Montes, H. M. Tabernero, J. I. Gonz\'alez Hern\'andez, E. Marfil, A. Frasca, A. C. Lanzafame, A. Klutsch, E. Franciosini, S. Randich, R. Smiljanic, A. J. Korn, G. Gilmore, E. J. Alfaro, T. Bensby, K. Biazzo, A. Casey, G. Carraro, F. Damiani, S. Feltzing, P. Fran\c{c}ois, F. Jim\'ene…

The Gaia-ESO Survey: Calibrating the lithium-age relation with open clusters and associations. II. Expanded cluster sample and final membership selection
The Li abundance observed in pre-main sequence and main sequence late-type stars is strongly age-dependent, but also shows a complex pattern depending on several parameters, such as rotation, chromospheric activity and metallicity. The best way to calibrate these effects, with the aim of studying Li as an age indicator for FGK stars, is to calibrate coeval groups of stars, such as open clusters (OCs) and associations. We present a considerable target sample of 42 OCs and associations, ranging f…

Probing particle acceleration in Abell 2256: from to 16 MHz to gamma rays
E. Osinga, R. J. van Weeren, G. Brunetti, R. Adam, K. Rajpurohit, A. Botteon, J. R. Callingham, V. Cuciti, F. de Gasperin, G. K. Miley, H. J. A. R\"ottgering, T. W. Shimwell
https://arxiv.org/abs/2405.09384

This https://arxiv.org/abs/2205.06020 has been replaced.
link: https://scholar.google.com/scholar?q=a

Hurwitz moduli varieties parameterizing Galois covers of an algebraic curve
Given a smooth, projective curve $Y$, a finite group $G$ and a positive integer $n$ we study smooth, proper families $X\to Y\times S\to S$ of Galois covers of $Y$ with Galois group isomorphic to $G$ branched in $n$ points, parameterized by algebraic varieties $S$. When $G$ is with trivial center we prove that the Hurwitz space $H^G_n(Y)$ is a fine moduli variety for this moduli problem and construct explicitly the universal family. For arbitrary $G$ we prove that $H^G_n(Y)$ is a coarse moduli v…

Diameter of 2-distance graphs
S. H. Jafari, S. R. Musawi
https://arxiv.org/abs/2403.07646 https://arxiv.org/pdf/2403.07646

Diameter of 2-distance graphs
For a simple graph $G$, the $2$-distance graph, $D_2(G)$, is a graph with the vertex set $V(G)$ and two vertices are adjacent if and only if their distance is $2$ in the graph $G$. In this paper, for graphs $G$ with diameter 2, we show that $diam(D_2(G))$ can be any integer $t\geqslant2$. For graphs $G$ with $diam(G)\geqslant3$, we prove that $\frac{1}{2}diam(G)\leqslant diam(D_2(G))$ and this inequality is sharp. Also, for $diam(G)=3$, we prove that $diam(D_2(G))\leqslant5$ and this inequality…

The Gaia-ESO Survey: Calibrating the lithium-age relation with open clusters and associations. II. Expanded cluster sample and final membership selection
M. L. Guti\'errez Albarr\'an, D. Montes, H. M. Tabernero, J. I. Gonz\'alez Hern\'andez, E. Marfil, A. Frasca, A. C. Lanzafame, A. Klutsch, E. Franciosini, S. Randich, R. Smiljanic, A. J. Korn, G. Gilmore, E. J. Alfaro, T. Bensby, K. Biazzo, A. Casey, G. Carraro, F. Damiani, S. Feltzing, P. Fran\c{c}ois, F. Jim\'ene…

The Gaia-ESO Survey: Calibrating the lithium-age relation with open clusters and associations. II. Expanded cluster sample and final membership selection
The Li abundance observed in pre-main sequence and main sequence late-type stars is strongly age-dependent, but also shows a complex pattern depending on several parameters, such as rotation, chromospheric activity and metallicity. The best way to calibrate these effects, with the aim of studying Li as an age indicator for FGK stars, is to calibrate coeval groups of stars, such as open clusters (OCs) and associations. We present a considerable target sample of 42 OCs and associations, ranging f…

Probing particle acceleration in Abell 2256: from to 16 MHz to gamma rays
E. Osinga, R. J. van Weeren, G. Brunetti, R. Adam, K. Rajpurohit, A. Botteon, J. R. Callingham, V. Cuciti, F. de Gasperin, G. K. Miley, H. J. A. R\"ottgering, T. W. Shimwell
https://arxiv.org/abs/2405.09384

PDRs4All IX. Sulfur elemental abundance in the Orion Bar
Asunci\'on Fuente, Evelyne Roueff, Franck Le Petit, Jacques Le Bourlot, Emeric Bron, Mark G. Wolfire, James F. Babb, Pei-Gen Yan, Takashi Onaka, John H. Black, Ilane Schroetter, Dries Van De Putte, Ameek Sidhu, Am\'elie Canin, Boris Trahin, Felipe Alarc\'on, Ryan Chown, Olga Kannavou, Olivier Bern\'e, Emilie Habart, Els Peeters, Javier R. Goicoechea, Marion Zannese, Raphael Meshaka, Yoko Okada, Markus R\"olli…

PDRs4All IX. Sulfur elemental abundance in the Orion Bar
One of the main problems in astrochemistry is determining the amount of sulfur in volatiles and refractories in the interstellar medium. The detection of the main sulfur reservoirs (icy H$_2$S and atomic gas) has been challenging, and estimates are based on the reliability of models to account for the abundances of species containing less than 1% of the total sulfur. The high sensitivity of the James Webb Space Telescope provides an unprecedented opportunity to estimate the sulfur abundance thr…

This https://arxiv.org/abs/2403.12756 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Hurwitz moduli varieties parameterizing pointed covers of an algebraic curve with a fixed monodromy group
Given a smooth, projective curve $Y$, a point $y_0 \in Y$, a positive integer $n$, and a transitive subgroup $G$ of the symmetric group $S_{d}$ we study smooth, proper families, parameterized by algebraic varieties, of pointed degree $d$ covers of $(Y,y_0)$, $(X,x_{0})\to (Y,y_0)$, branched in $n$ points of $Y\setminus y_{0}$, whose monodromy group equals $G$. We construct a Hurwitz space $H$, an algebraic variety whose points are in bijective correspondence with the equivalence classes of poin…

Structural properties of amorphous Na$_3$OCl electrolyte by first-principles and machine learning molecular dynamics
T. -L. Pham, M. Guerboub, S. D. Wansi Wendj, A. Bouzid, C. Tug\`ene, M. Boero, C. Massobrio, Y. -H. Shin, G. Ori
https://arxiv.org/abs/2404.11442

Structural properties of amorphous Na$_3$OCl electrolyte by first-principles and machine learning molecular dynamics
Solid-state electrolytes mark a significant leap forward in the field of electrochemical energy storage, offering improved safety and efficiency compared to conventional liquid electrolytes. Among these, antiperovskite electrolytes, particularly those based on Li and Na, have emerged as promising candidates due to their superior ionic conductivity and straightforward synthesis processes. This study focuses on the amorphous phase of antiperovskite Na$_3$OCl, assessing its structural properties t…

This https://arxiv.org/abs/2306.10375 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Weak saturation numbers in random graphs
For two given graphs $G$ and $F$, a graph $ H$ is said to be weakly $ (G, F) $-saturated if $H$ is a spanning subgraph of $ G$ which has no copy of $F$ as a subgraph and one can add all edges in $ E(G)\setminus E(H)$ to $ H$ in some order so that a new copy of $F$ is created at each step. The weak saturation number $ wsat(G, F)$ is the minimum number of edges of a weakly $(G, F)$-saturated graph. In this paper, we deal with the relation between $ wsat(G(n,p), F)$ and $ wsat(K_n, F)$, where $G(n…

This https://arxiv.org/abs/2306.17294 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Alternating cochains on Furstenberg boundaries and measurable cohomology
Nicolas Monod showed that the evaluation map $$H^*_m(G\curvearrowright G/P)\longrightarrow H^*_m(G)$$ between the measurable cohomology of the action of a connected semisimple Lie group $G$ on its Furstenberg boundary $G/P$ and the measurable cohomology of $G$ is surjective with a non-trivial kernel in all degrees below a constant depending on $G$ and less than or equal to the rank of $G$ plus $2$. When we were looking for explicit representatives of classes in this kernel, we were astonished t…

Effective correlation and decorrelation for newforms, and weak subconvexity for $L$-functions
Nawapan Wattanawanichkul
https://arxiv.org/abs/2405.05249 htt…

Effective correlation and decorrelation for newforms, and weak subconvexity for $L$-functions
Let $f$ and $g$ be spectrally normalized holomorphic newforms of even weight $k \geq2$ on $Γ_0(q)$. If $f\neq g$, then assume that $q$ is squarefree. For a nice test function $ψ$ supported on $Γ_0(1)\backslash\mathbb{H}$, we establish the best known bounds (uniform in $k$, $q$, and $ψ$) for \[ \int_{Γ_0(q)\backslash\mathbb{H}}ψ(z)f(z)\overline{g(z)}y^{k}\frac{dxdy}{y^2}-\mathbf{1}_{f = g}\frac{3}π\int_{Γ_0(1)\backslash\mathbb{H}}ψ(z)\frac{dx dy}{y^2}.\] When $f=g$, our results yield an…

An impressionist view of V Hydrae. When MATISSE paints Asymmetric Giant Blobs
L. Planquart, C. Paladini, A. Jorissen, A. Escorza, E. Pantin, J. Drevon, B. Aringer, F. Baron, A. Chiavassa, P. Cruzal\`ebes, W. Danchi, E. De Beck, M. A. T. Groenewegen, S. H\"ofner, J. Hron, T. Khouri, B. Lopez, F. Lykou, M. Montarges, N. Nardetto, K. Ohnaka, H. Olofsson, G. Rau, A. Rosales-Guzm\'an, J. Sanchez-Bermudez, P. Scicluna, L. Siess, F. Th\'evenin, S. Van Eck, W. H. T. Vlemmings, G. …

This https://arxiv.org/abs/2307.06155 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

Relative Fractional Independence Number and Its Applications
We define the relative fractional independence number of a graph $G$ with respect to another graph $H$, as $$α^*(G|H)=\max_{W}\frac{α(G\boxtimes W)}{α(H\boxtimes W)},$$ where the maximum is taken over all graphs $W$, $G\boxtimes W$ is the strong product of $G$ and $W$, and $α$ denotes the independence number. We give a non-trivial linear program to compute $α^*(G|H)$ and discuss some of its properties. We show that $α^*(G|H)\geq \frac{X(G)}{X(H)} \geq \frac{1}{α^*(H|G…

Discovery of Very-high-energy Gamma-ray Emissions from the Low Luminosity AGN NGC 4278 by LHAASO
Zhen Cao, F. Aharonian, Q. An, Axikegu, Y. X. Bai, Y. W. Bao, D. Bastieri, X. J. Bi, Y. J. Bi, J. T. Cai, Q. Cao, W. Y. Cao, Zhe Cao, J. Chang, J. F. Chang, A. M. Chen, E. S. Chen, Liang Chen, Lin Chen, Long Chen, M. J. Chen, M. L. Chen, Q. H. Chen, S. H. Chen, S. Z. Chen, T. L. Chen, Y. Chen, N. Cheng, Y. D. Cheng, M. Y. Cui, S. W. Cui, X. H. Cui, Y. D. Cui, B. Z. Dai, H. L. Dai, Z. G. Da…

Spherical $p$-group complexes arising from finite groups of Lie type
Kevin Iv\'an Piterman
https://arxiv.org/abs/2403.07489 https://

Spherical $p$-group complexes arising from finite groups of Lie type
We show that the $p$-group complex of a finite group $G$ is homotopy equivalent to a wedge of spheres of dimension at most $n$ if $G$ contains a self-centralising normal subgroup $H$ which is isomorphic to a group of Lie type and Lie rank $n$ in characteristic $p$. If in addition every order-$p$ element of $G$ induces an inner or field automorphism on $H$, the $p$-group complex of $G$ is $G$-homotopy equivalent to a spherical complex obtained from the Tits building of $H$. We also prove that …

On the Erd\H{o}s-Tur\'an Conjecture and the growth of $B_{2}[g]$ sequences
Javier Pliego
https://arxiv.org/abs/2405.04154 https://

On the Erdős-Turán Conjecture and the growth of $B_{2}[g]$ sequences
When $g\in\mathbb{N}$ we say that $A\subset\mathbb{N}$ is a $B_{2}[g]$ sequence if every $m\in\mathbb{N}$ has at most $g$ distinct representations of the shape $m=b_{1}+b_{2}$ with $b_{1}\leq b_{2}$ and $b_{1},b_{2}\in A$. We show for every $0<\varepsilon<1$ that whenever $g>\frac{1}{\varepsilon}$ then there is a $B_{2}[g]$ sequence $A$ having the property that every sufficiently large $n\in\mathbb{N}$ can be written as $$n=a_{1}+a_{2}+a_{3},\ \ \ \ \ \ \ \ \ a_{3}\leq n^{\varepsilon}\ \ \ \ \ …

An impressionist view of V Hydrae. When MATISSE paints Asymmetric Giant Blobs
L. Planquart, C. Paladini, A. Jorissen, A. Escorza, E. Pantin, J. Drevon, B. Aringer, F. Baron, A. Chiavassa, P. Cruzal\`ebes, W. Danchi, E. De Beck, M. A. T. Groenewegen, S. H\"ofner, J. Hron, T. Khouri, B. Lopez, F. Lykou, M. Montarges, N. Nardetto, K. Ohnaka, H. Olofsson, G. Rau, A. Rosales-Guzm\'an, J. Sanchez-Bermudez, P. Scicluna, L. Siess, F. Th\'evenin, S. Van Eck, W. H. T. Vlemmings, G. …

This https://arxiv.org/abs/2102.13639 has been replaced.
link: https://scholar.google.com/scholar?q=a

Orbifold Semiorthogonal Decompositions for Abelian Varieties
Suppose $G$ is a finite group acting on an Abelian variety $A$ such that the coarse moduli space $A/G$ is smooth. Using the recent classification result due to Auffarth, Lucchini Arteche, and Quezada, we construct an orbifold semiorthogonal decomposition for $\mathcal{D}[A/G]$ provided $G = T\rtimes H$ with $T$ a subgroup of translations and $H$ is a subgroup of group automorphisms.

Genus and crosscap of Normal subgroup based power graphs of finite groups
Parveen, Manisha, Jitender Kumar
https://arxiv.org/abs/2404.03895 https://

Genus and crosscap of Normal subgroup based power graphs of finite groups
Let $H$ be a normal subgroup of a group $G$. The normal subgroup based power graph $Γ_H(G)$ of $G$ is the simple undirected graph with vertex set $V(Γ_H(G))= (G\setminus H)\cup \{e\}$ and two distinct vertices $a$ and $b$ are adjacent if either $aH = b^m H$ or $bH=a^nH$ for some $m,n \in \mathbb{N}$. In this paper, we continue the study of normal subgroup based power graph and characterize all the pairs $(G,H)$, where $H$ is a non-trivial normal subgroup of $G$, such that the genus of $Γ_H(G…

Height Filtrations and Base Loci on Flag Bundles over a Curve
Yangyu Fan, Wenbin Luo, Binggang Qu
https://arxiv.org/abs/2403.06808 https://

Height Filtrations and Base Loci on Flag Bundles over a Curve
Let $k$ be an algebraically closed field of characteristic zero. Let $C/k$ be a projective smooth curve with function field $K=k(C)$ and $G/k$ be a connected reductive group. Let $F$ be a principal $G$-bundle on $C$. Let $P \subseteq G$ be a parabolic subgroup and $λ: P \longrightarrow G$ be a strictly anti-dominant character. Then $F/P \longrightarrow C$ is a flag bundle and $\mathcal{L}_λ=F \times_P k_λ$ on $F/P$ is a relatively ample line bundle. Let $h_{\mathcal{L}_λ}$ be the height f…

This https://arxiv.org/abs/2102.13639 has been replaced.
link: https://scholar.google.com/scholar?q=a

Orbifold Semiorthogonal Decompositions for Abelian Varieties
Suppose $G$ is a finite group acting on an Abelian variety $A$ such that the coarse moduli space $A/G$ is smooth. Using the recent classification result due to Auffarth, Lucchini Arteche, and Quezada, we construct an orbifold semiorthogonal decomposition for $\mathcal{D}[A/G]$ provided $G = T\rtimes H$ with $T$ a subgroup of translations and $H$ is a subgroup of group automorphisms.

The impact of radiative levitation on mode excitation of main-sequence B-type pulsators
R. Rehm, J. S. G. Mombarg, C. Aerts, M. Michielsen, S. Burssens, R. H. D. Townsend
https://arxiv.org/abs/2405.08864

Fractional distortion in hyperbolic groups
Pallavi Dani, Timothy Riley
https://arxiv.org/abs/2403.08645 https://arxiv.org/pdf/2403.08…

Fractional distortion in hyperbolic groups
For all integers $p>q>0$ and $k >0$, and all non-elementary torsion-free hyperbolic groups $H$, we construct a hyperbolic group $G$ in which $H$ is a subgroup, such that the distortion function of $H$ in $G$ grows like $\exp^k(n^{p/q})$. Here, $\exp^k$ denotes the $k$-fold-iterated exponential function.

The Strong Nine Dragon Tree Conjecture is True for $d \leq 2(k 1)$
Sebastian Mies, Benjamin Moore
https://arxiv.org/abs/2403.05178 https://

The Strong Nine Dragon Tree Conjecture is True for $d \leq 2(k+1)$
The arboricity $Γ(G)$ of an undirected graph $G =(V,E)$ is the minimal number $k$ such that $E$ can be partitioned into $k$ forests on $V$. Nash-Williams' formula states that $k = \lceil γ(G) \rceil$, where $γ(G)$ is the maximum of $\frac{|E_{H}|}{|V_{H}|-1}$ over all subgraphs $(V_H , E_H )$ of $G$ with $|V_H | \geq 2$. The Strong Nine Dragon Tree Conjecture states that if $γ(G) \leq k + \frac{d}{d+k+1}$ for $k, d \in \mathbb{N}$, then there is a partition of …

Height Filtrations and Base Loci on Flag Bundles over a Curve
Yangyu Fan, Wenbin Luo, Binggang Qu
https://arxiv.org/abs/2403.06808 https://

Height Filtrations and Base Loci on Flag Bundles over a Curve
Let $k$ be an algebraically closed field of characteristic zero. Let $C/k$ be a projective smooth curve with function field $K=k(C)$ and $G/k$ be a connected reductive group. Let $F$ be a principal $G$-bundle on $C$. Let $P \subseteq G$ be a parabolic subgroup and $λ: P \longrightarrow G$ be a strictly anti-dominant character. Then $F/P \longrightarrow C$ is a flag bundle and $\mathcal{L}_λ=F \times_P k_λ$ on $F/P$ is a relatively ample line bundle. Let $h_{\mathcal{L}_λ}$ be the height f…

Fractional distortion in hyperbolic groups
Pallavi Dani, Timothy Riley
https://arxiv.org/abs/2403.08645 https://arxiv.org/pdf/2403.08…

Fractional distortion in hyperbolic groups
For all integers $p>q>0$ and $k >0$, and all non-elementary torsion-free hyperbolic groups $H$, we construct a hyperbolic group $G$ in which $H$ is a subgroup, such that the distortion function of $H$ in $G$ grows like $\exp^k(n^{p/q})$. Here, $\exp^k$ denotes the $k$-fold-iterated exponential function.

Searching for evidence of subchromospheric magnetic reconnection on the Sun
D. Baker, L. van Driel-Gesztelyi, A. W. James, P. Demoulin, A. S. H. To, M. Murabito, D. M. Long, D. H. Brooks, J. McKevitt, J. M. Laming, L. M. Green, S. L. Yardley, G. Valori, T. Mihailescu, S. A. Matthews, H. Kuniyoshi
https://arxiv.org/abs/2405.07755…

Searching for evidence of subchromospheric magnetic reconnection on the Sun
D. Baker, L. van Driel-Gesztelyi, A. W. James, P. Demoulin, A. S. H. To, M. Murabito, D. M. Long, D. H. Brooks, J. McKevitt, J. M. Laming, L. M. Green, S. L. Yardley, G. Valori, T. Mihailescu, S. A. Matthews, H. Kuniyoshi
https://arxiv.org/abs/2405.07755…

This https://arxiv.org/abs/2308.13255 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_mat…

A lower bound on the multicolor size-Ramsey numbers of paths in hypergraphs
The $r$-color size-Ramsey number of a $k$-uniform hypergraph $H$, denoted by $\hat{R}_r(H)$, is the minimum number of edges in a $k$-uniform hypergraph $G$ such that for every $r$-coloring of the edges of $G$ there exists a monochromatic copy of $H$. In the case of $2$-uniform paths $P_n$, it is known that $Ω(r^2n)=\hat{R}_r(P_n)=O((r^2\log r)n)$ with the best bounds essentially due to Krivelevich. In a recent breakthrough result, Letzter, Pokrovskiy, and Yepremyan gave a linear upper bound on…

Groups with supersolvable automorphism group
Benjamin Sambale
https://arxiv.org/abs/2403.05926 https://arxiv.org/pdf/2403.05926

Groups with supersolvable automorphism group
We call a finite group G ultrasolvable if it has a characteristic subgroup series whose factors are cyclic. It was shown by Durbin--McDonald that the automorphism group of an ultrasolvable group is supersolvable. The converse statement was established by Baartmans--Woeppel under the hypothesis that G has no direct factor isomorphic to the Klein four-group. We extend this result by proving that Aut(G) is supersolvable if and only if G is ultrasolvable or G=H\times C_2\times C_2 where H is ultras…

Absolute dimensions of solar-type eclipsing binaries. NY Hya: A test for magnetic stellar evolution models
T. C. Hinse, O. Ba\c{s}t\"urk, J. Southworth, G. A. Feiden, J. Tregloan-Reed, V. B. Kostov, J. Livingston, E. M. Esmer, Mesut Y{\i}lmaz, Sel\c{c}uk Yal\c{c}{\i}nkaya, \c{S}eyma Torun, J. Vos, D. F. Evans, J. C. Morales, J. C. A. Wolf, E. H. Olsen, J. V. Clausen, B. E. Helt, C. T. K. L\'y, O. Stahl, R. Wells, M. Herath, U. G. J{\o}rgensen, M. Dominik, J. Skottfelt, N. Peix…

Absolute dimensions of solar-type eclipsing binaries. NY Hya: A test for magnetic stellar evolution models
The binary star NY Hya is a bright, detached, double-lined eclipsing system with an orbital period of just under five days with two components each nearly identical to the Sun and located in the solar neighbourhood. The objective of this study is to test and confront various stellar evolution models for solar-type stars based on accurate measurements of stellar mass and radius. We present new ground-based spectroscopic and photometric as well as high-precision space-based photometric and as…

General position sets, colinear sets, and Sierpi\'{n}ski product graphs
Sandi Klav\v{z}ar, Jing Tian
https://arxiv.org/abs/2404.05481 https://

General position sets, colinear sets, and Sierpiński product graphs
Let $G \otimes _f H$ denote the Sierpiński product of $G$ and $H$ with respect to the function $f$. The Sierpiński general position number ${\rm gp}{_{\rm S}}(G,H)$ is introduced as the cardinality of a largest general position set in $G \otimes _f H$ over all possible functions $f$. Similarly, the lower Sierpiński general position number $\underline{\rm gp}{_{\rm S}}(G,H)$ is the corresponding smallest cardinality. The concept of vertex-colinear sets is introduced. Bounds for the general po…

This https://arxiv.org/abs/2205.12826 has been replaced.
link: https://scholar.google.com/scholar?q=a

Two Ramsey problems in blowups of graphs
Given graphs $G$ and $H$, we say $G \stackrel{r}{\to} H$ if every $r$-colouring of the edges of $G$ contains a monochromatic copy of $H$. Let $H[t]$ denote the $t$-blowup of $H$. The blowup Ramsey number $B(G \stackrel{r}{\to} H;t)$ is the minimum $n$ such that $G[n] \stackrel{r}{\to} H[t]$. Fox, Luo and Wigderson refined an upper bound of Souza, showing that, given $G$, $H$ and $r$ such that $G \stackrel{r}{\to} H$, there exist constants $a=a(G,H,r)$ and $b=b(H,r)$ such that for all $t \in \ma…

Partition of Sparse Graphs into Two Forests with Bounded Degree
Matthew Yancey
https://arxiv.org/abs/2403.05387 https://arxiv.org/pdf…

Partition of Sparse Graphs into Two Forests with Bounded Degree
Borodin and Kostochka proved that for $d_2 \geq 2d_1+2$ and a graph $G$ where every subgraph $H$ satisfies $$ e(H) < \left(2 - \frac{d_2+2}{(d_1+2)(d_2+1)}\right)n(H) + \frac{1}{d_2+1} $$ has a vertex partition $V(G) = V_1 \cup V_2$ such that $G[V_i]$ has maximum degree at most $d_i$ for each $i$. We show that under the same conditions we can additionally conclude that each $G[V_i]$ is a forest.

Counterexamples to two conjectures on mean color numbers of graphs
Wushuang Zhai, Yan Yang
https://arxiv.org/abs/2405.01890 https://a…

Counterexamples to two conjectures on mean color numbers of graphs
The mean color number of an $n$-vertex graph $G$, denoted by $μ(G)$, is the average number of colors used in all proper $n$-colorings of $G$. For any graph $G$ and a vertex $w$ in $G$, Dong (2003) conjectured that if $H$ is a graph obtained from a graph $G$ by deleting all but one of the edges which are incident to $w$, then $μ(G)\geq μ(H)$; and also conjectured that $μ(G)\geq μ((G-w)\cup K_1)$. We prove that there is an infinite family of counterexamples to these two conjectures.