Tootfinder

Looong train ride, and a very long EV drive later and we have arrived in the Alps.
It's 20C and raining.
⛈️🌦️🌧️☔
We may have been too successful in escaping the current European #Heatwave.
😅

Google Search AI is trying to cheer me up by making up the most silly summaries.
It is kind of working.

Trump: “I'm not satisfied with Putin” !: https://benborges.xyz/2025/07/12/trump-im-not-satisfied-with.html

#til
The built in calculator app on the iPhone can do all sorts of conversions.
Long-press the icon at bottom left and you get a pop-up menu. Slide the toggle on and the default $ to € currency converter appears. There’s a bazillion other currencies available too. But you can also choose among 15 other unit conversions, like weights, energy, force, pressure.

Mr. Abrego Garcia, speaking through an interpreter, has entered "not guilty" pleas to the two charges
@tennesseelookout.com
https://bsky.app/profile/anitawadhwani.bsky.social/post/3lripyl3g5s2q

I suppose #Caturday is strong

Pam Ayres
At last, we have a cure for all!
Ailments large and ailments small,
Good health is not beyond my reach,
If I inject myself with bleach.
Radiant, I’ll prance along,
Every trace of limescale gone,
With disinfectant as my friend,
Like him,
I’m clean around the bend.

I uploaded my original announcement #tvamrks video to youtube in hope to get more people to find it.
If you could give it a thumbs up or a comment that would be super cool of you!
https://www.youtube.com/wat…

nach vielen Versuchen gelang mir heute ein mittelgroßer Durchbruch beim Finetuning von #ParzivAI v0.2 - ParzivAI kann jetzt reasoning!
Und bald gibt es mehr dazu!
#DH #Mittelhochdeutsch

AI futures: Culture wars https://musicindustryblog.wordpress.com/2025/06/05/ai-futures-culture-wars/?utm_source=dlvr.it&utm_content=muz4now/magazine/Copy…

AI futures: Culture wars
AI is transforming culture, entertainment, business, and society at a pace unprecedented in the digital era. Unlike previous tech, AI is evolving at the speed of computing, not the speed of the hum…

Ende des Liveblogs
Wir schließen den Liveblog für heute und bedanken uns für Ihr Interesse.
📑 https://www.tagesschau.de/newsticker/liveblog-ukraine-sonntag-572.html?at_medium=mastodon&at_camp…

Ukraine-Liveblog: ++ Frankreich rüstet massiv auf ++
Angesichts der russischen Bedrohung erhöht Frankreich seinen Verteidigungsetat drastisch. Die Internationale Atomenergieagentur berichtet von Schüssen an dem von Russland besetzten Atomkraftwerk Saporischschja.

Okay, so I'd already seen the first half of this video where he's pushed out of the room by thugs and.. I mean that's bad, but also that kind of thing happens all the time.
I was unprepared for the second half of the video, where they place a US Senator on the ground and CUFF HIS HANDS BEHIND HIS BACK for _verbally_ interrupting a press briefing. 👀

Hotwire - Invisible
#rock

From Fort Bragg to L.A., Trump enlists the military in a slow-motion coup (Will Bunch/The Philadelphia Inquirer)
https://www.inquirer.com/opinion/coup-military-parade-national-guard-deployment-protest-trump-20250612.html
http://www.memeorandum.com/250612/p114#a250612p114

Dust production rates in Jupiter-family comets II: Trends and population insights from ATLAS photometry of 116 JFCs
A. Fraser Gillan, Alan Fitzsimmons, Larry Denneau, Robert J. Siverd, Ken W. Smith, John L. Tonry, David R. Young
https://arxiv.org/abs/2506.09192

Dust production rates in Jupiter-family comets II: Trends and population insights from ATLAS photometry of 116 JFCs
Jupiter-family comets (JFCs) have orbital periods of less than 20 years and therefore undergo more frequent sublimation compared to other comet populations. The JFCs therefore represent the ideal dynamical population for investigating the dust production rates at high-cadence. We analyzed observations by the Asteroid Terrestrial-impact Last Alert System (ATLAS) of 74 JFCs that reached perihelion in 2022 and 2023. The work contained in this study builds upon our previous work (Gillan et al. 2024…

Efficient multigrid solvers for mixed-degree local discontinuous Galerkin multiphase Stokes problems
Robert I. Saye
https://arxiv.org/abs/2506.09933 https:…

Efficient multigrid solvers for mixed-degree local discontinuous Galerkin multiphase Stokes problems
We design and investigate efficient multigrid solvers for multiphase Stokes problems discretised via mixed-degree local discontinuous Galerkin methods. Using the template of a standard multigrid V-cycle, we develop a smoother analogous to element-wise block Gauss-Seidel, except the diagonal block inverses are replaced with an approximation that balances the smoothing of the velocity and pressure variables, factoring in the unequal scaling of the various Stokes system operators, and optimised vi…

Sen. Alex Padilla handcuffed at DHS press conference: Full video
https://www.cnbc.com/2025/06/12/alex-padilla-noem-dhs-handcuffed.html

Linus Torvalds goes back to a mechanical keyboard after making too many typos https://www.theregister.com/2025/05/13/linux_6_15_rc6_keyboards/
This change will cost Mr. Torvalds a lot of money. It's another rabbit hole down which your money is dippi…

Hyperfixiation Joy, Stay if You Love It, Scroll if You Don’t!
Next year marks a decade since I first heard Loin d’ici by Zoë Straub. Ten years of the same song looping in my mind, ten years of clinging to every word, every note, as if it’s the only thing keeping me afloat. I remember May 14, 2016, like it’s a scar, the day my hyperfixation began. Time keeps slipping past me, but the song stays, haunting and comforting at once, as if Zoë herself is quietly following me through the endle…

Watched a video about how #Bluesky is dying and that #Twitter is the bastion of social media.
All their points come from random Reddit threads with 2,000 members.
😂😂😂

The story of my grandfather, Arthur Ward, has been published by the Society of Genealogists in the Genealogists’ Magazine. #WW1

Arthur Ward (1888-1948) - Miscellanea Edintone
The story of my grandfather, Arthur Ward, has been published by the Society of Genealogists in the Genealogists' Magazine.

Series B, Episode 05 - Pressure Point
JENNA: You're suggesting that we go into the Forbidden Zone and attack Control?
BLAKE: Yes, that is what I am suggesting.
CALLY: Do we know where this computer complex is?
JENNA: Most Earth people have heard of it.
https://blake.torpidity.net/m/205/49

🇺🇦 #NowPlaying on KEXP's #MiddayShow
Dead Pioneers:
🎵 PO$T AMERICAN
#DeadPioneers
https://deadpioneers.bandcamp.com/track/stfu
https://open.spotify.com/track/5QqeLxGnVM0wLIE3hcvCde

Studie: KI-Therapie-Bots geben mörderische Tipps und verletzen Leitlinien
Beliebte Chatbots sind kein guter Ersatz für menschliche Therapeuten. Forscher mahnen zu mehr Fingerspitzengefühl beim Einsatz von ChatGPT & Co. als Berater.

Afff, tenho muito mais coisas pra corrigir (em všrias disciplinas) do que pensava. 😢
É o aspecto desse trabalho que eu mais odeio, ter que corrigir provas e trabalhos.

Binnen is het 21,6 °C
Buiten is het 27,1 °C
Dus is het geen goed idee om de ramen te openen voor koelte.
De door de balansventilatie aangezogen ventilatielucht wordt ontdaan van BBQ-fijnstof en min of meer op de binnentemperatuur gebracht via de warmtewisselaar.
Dat klinkt belachelijk luxe, en dat is het helaas ook. Gezonde lucht is een onderschat mensenrecht.
#vanGasLos

Combover Caligula
bot by @…
This is satire, not sedition: put the zip ties down.
#satire #potus45

LOL, Batman on Sinclair QL
https://badared.com/badaman/ql/batman/batman-en.html

Replaced article(s) found for cs.DM. https://arxiv.org/list/cs.DM/new/
[1/1]:
Logic-Constrained Shortest Paths for Flight Planning
https://

Special Tribunal for the Kremlin: a historic decision in the making: https://benborges.xyz/2025/07/12/special-tribunal-for-the-kremlin.html

The Grand Canyon Lodge,
the only lodging inside the park at the North Rim,
was consumed by the flames,
park Superintendent Ed Keable told park residents, staff and others in a meeting Sunday morning.
https://bsky.app/profile/pbsnews.org/post/3lturjh5k2a2h…

Ende des Liveblogs
Wir beenden an dieser Stelle für heute den Liveblog und bedanken uns für Ihr Interesse.
📑 https://www.tagesschau.de/newsticker/liveblog-ukraine-samstag-540.html?at_medium=masto…

Ukraine-Liveblog: ++ Strom- und Wasserausfall in besetzten Gebieten ++
Weite Teile der von russischen Truppen besetzten südukrainischen Region Saporischschja sind ohne Strom- und Wasserversorgung. Durch russische Angriffe sollen mindestens vier Menschen in der Ukraine getötet worden sein.

A discontinuous Galerkin plane wave neural network method for Helmholtz equation and Maxwell's equations
Long Yuan, Menghui Wu, Qiya Hu
https://arxiv.org/abs/2506.09309

A discontinuous Galerkin plane wave neural network method for Helmholtz equation and Maxwell's equations
In this paper we propose a discontinuous Galerkin plane wave neural network (DGPWNN) method for approximately solving Helmholtz equation and Maxwell's equations. In this method, we define an elliptic-type variational problem as in the plane wave least square method with $h-$refinement and introduce the adaptive construction of recursively augmented discontinuous Galerkin subspaces whose basis functions are realizations of element-wise neural network functions with $hp-$refinement, where the act…

Down But Not Out: The Case of Long-Period Comet C/2021 O3 (Panstarrs)
David Jewitt. Jing Li, Michael Jaeger, Yoonyoung Kim
https://arxiv.org/abs/2506.09263

Down But Not Out: The Case of Long-Period Comet C/2021 O3 (Panstarrs)
We combine ground- and space-based observations of long-period comet C/2021 O3 (Panstarrs) (perihelion distance 0.287 au) in order to investigate its reported near-perihelion destruction. Pre-perihelion photometric observations show a remarkably small heliocentric dependence of the scattered light, $\propto r_H^{-s}$ with $s = 2.59\pm0.21$, distinct from values reported in other long-period comets, for which $s$ = 4 is the canonical standard. The index is smaller than expected of coma productio…

🇺🇦 #NowPlaying on KEXP's #MiddayShow
Rage Against the Machine:
🎵 Wake Up
#RageAgainsttheMachine
https://respeakr.bandcamp.com/track/sinking-enei-wake-up-rage-against-the-machine
https://open.spotify.com/track/2QiqwOVUctPRVggO9G1Zs5

Today, I tested the "Record Track" feature in @… during my bike ride in Bergen, Norway. 🙌
I’m already a fan of Organic Maps, and this feature worked very well for tracking my route on GrapheneOS.
Highly recommended for anyone looking to log their outdoor adventures! 🚴‍♂️

Some @… vibes.

Erfolg für Trump: EU-Kommission will Digitalsteuer aus Haushaltsplan streichen
Das Aufschieben des Plans für eine Digitalsteuer sollte der EU bei den Zollverhandlungen mit den USA helfen. Der Rückzieher kommt bereits nach zwei Monaten.

[2025-06-12 Thu (UTC), no new articles found for cs.DM Discrete Mathematics]
toXiv_bot_toot

Ukraine war latest: German-funded long-range weapons to arrive in Ukraine by late July; NATO chief to visit Washington on July 14 as Trump prepares 'major statement' on Russia: https://benborges.xyz/2025/07/13/ukraine-war-latest-germanfunded-longrange.html…

Ende des Liveblogs
Damit beenden wir diesen Liveblog und danken für Ihr Interesse.
📑 https://www.tagesschau.de/newsticker/liveblog-ukraine-donnerstag-478.html?at_medium=mastodon&at_campaig…

Ukraine-Liveblog: ++ Trump kritisiert Moskau und Kiew ++
US-Präsident Trump äußert sich wegen der bisher weitgehend erfolglosen Verhandlungen enttäuscht von Russland und der Ukraine. Verteidigungsminister Pistorius stellt der Ukraine weitere Militärhilfen in Milliardenhöhe in Aussicht.

Improved error bounds for Koopman operator and reconstructed trajectories approximations with kernel-based methods
Diego Olgu\'in, Axel Osses, H\'ector Ram\'irez
https://arxiv.org/abs/2506.09266

Improved error bounds for Koopman operator and reconstructed trajectories approximations with kernel-based methods
In this article, we propose a new error bound for Koopman operator approximation using Kernel Extended Dynamic Mode Decomposition. The new estimate is $O(N^{-1/2})$, with a constant related to the probability of success of the bound, given by Hoeffding's inequality, similar to other methodologies, such as Philipp et al. Furthermore, we propose a \textit{lifting back} operator to obtain trajectories generated by embedding the initial state and iterating a linear system in a higher dimension. Thi…

🇺🇦 #NowPlaying on KEXP's #MiddayShow
Beastie Boys:
🎵 Sabotage
#BeastieBoys
https://louisbrains.bandcamp.com/track/beastie-boys-sabotage-louis-brains-remix
https://open.spotify.com/track/2L39OtNfhUKQ7VbOAVoaZL

Replaced article(s) found for astro-ph.EP. https://arxiv.org/list/astro-ph.EP/new/
[1/1]:
Impact chronology of leftover planetesimals
…

Russian attacks across Ukraine kill 7, injure 21 over past day: https://benborges.xyz/2025/07/13/russian-attacks-across-ukraine-kill.html

🇺🇦 #NowPlaying on KEXP's #MiddayShow
The Staple Singers:
🎵 I'll Take You There
#TheStapleSingers
https://khristiank.bandcamp.com/track/the-staple-singers-ill-take-you-there-khristian-k-edit
https://open.spotify.com/track/5YLnfy7R2kueN0BRPkjiEG

MINDS: Detection of an inner gas disk caused by evaporating bodies around HD 172555
M. Samland, T. Henning, A. Caratti o Garatti, T. Giannini, J. Bouwman, B. Tabone, A. M. Arabhavi, G. Olofsson, M. G\"udel, N. Pawellek, I. Kamp, L. B. F. M. Waters, D. Semenov, E. F. van Dishoeck, O. Absil, D. Barrado, A. Boccaletti, V. Christiaens, D. Gasman, S. L. Grant, H. Jang, T. Kaeufer, J. Kanwar, G. Perotti, K. Schwarz, M. Temmink

MINDS: Detection of an inner gas disk caused by evaporating bodies around HD 172555
Mechanisms such as collisions of rocky bodies or cometary activity give rise to dusty debris disks. Debris disks trace the leftover building blocks of planets, and thus also planetary composition. HD 172555, a stellar twin of beta Pic, hosts a debris disk thought to have resulted from a giant collision. It is known for its extreme mid-infrared silica dust feature, indicating a warm population of silica-rich grains in the asteroid belt (~5 au), cold CO observed by ALMA, and small bodies evaporat…

Replaced article(s) found for math.NA. https://arxiv.org/list/math.NA/new/
[1/1]:
Efficient implicit solvers for models of neuronal networks
https…

🇺🇦 #NowPlaying on KEXP's #MiddayShow
Nina Simone:
🎵 I Wish I Knew How It Would Feel to Be Free
#NinaSimone
https://sfbdhq.bandcamp.com/track/nina-simone-i-wish-i-knew-how-it-would-feel-to-be-free
https://open.spotify.com/track/5CKHhg31HcYYhwUeeGqvhq

Study of Venera Spacecraft Trajectories and Wider Implications
Adam Hibberd
https://arxiv.org/abs/2506.09478 https://arxiv.org/pdf/25…

Study of Venera Spacecraft Trajectories and Wider Implications
Historically, there is no doubt that the early years of the USSR space program put them way ahead of the competition (the USA). Nonetheless, although this was not what the Russians wished to present to the world, the interplanetary campaign, centred around missions to the planet Venus (the Venera program) was also beset with difficulties. Many of the early Venera probes failed, despite making it to a heliocentric orbit, but naturally the success rate improved with time. The result is that there…

A Note on the Reliability of Goal-Oriented Error Estimates for Galerkin Finite Element Methods with Nonlinear Functionals
Brian N. Granzow, Stephen D. Bond, D. Thomas Seidl, Bernhard Endtmayer
https://arxiv.org/abs/2506.09913

A Note on the Reliability of Goal-Oriented Error Estimates for Galerkin Finite Element Methods with Nonlinear Functionals
We consider estimating the discretization error in a nonlinear functional $J(u)$ in the setting of an abstract variational problem: find $u \in \mathcal{V}$ such that $B(u,φ) = L(φ) \; \forall φ\in \mathcal{V}$, as approximated by a Galerkin finite element method. Here, $\mathcal{V}$ is a Hilbert space, $B(\cdot,\cdot)$ is a bilinear form, and $L(\cdot)$ is a linear functional. We consider well-known error estimates $η$ of the form $J(u) - J(u_h) \approx η= L(z) - B(u_h, z)$, where $u_h$ d…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Queen Latifah:
🎵 U.N.I.T.Y.
#QueenLatifah
https://elizabethmusic.bandcamp.com/track/are-you-afraid-of-the-u-n-i-t-y-queen-latifah-elizab-th-mashup

Improved H2-He and H2-H2 Collision-Induced Absorption Models and Application to Outer-Planet Atmospheres
Glenn S. Orton, Magnus Gustafsson, Leigh N. Fletcher, Michael T. Roman, James A. Sinclair
https://arxiv.org/abs/2506.09257

Improved H2-He and H2-H2 Collision-Induced Absorption Models and Application to Outer-Planet Atmospheres
Using state-of-the-art ab initio interaction-induced dipole and potential-energy surfaces for hydrogen-helium (H2-He) pairs, we compute the rototranslational collision-induced absorption coefficient at 40-400 K for frequencies covering 0-4000 cm-1. The quantum mechanical scattering calculations account for the full anisotropic interaction potential, replacing the isotropic approximation. The absorption data are expected to be accurate with an uncertainty of 2% or better up to 2500 cm-1. The unc…

Machine Learning-based quadratic closures for non-intrusive Reduced Order Models
Gabriele Codega, Anna Ivagnes, Nicola Demo, Gianluigi Rozza
https://arxiv.org/abs/2506.09830

Machine Learning-based quadratic closures for non-intrusive Reduced Order Models
In the present work, we introduce a data-driven approach to enhance the accuracy of non-intrusive Reduced Order Models (ROMs). In particular, we focus on ROMs built using Proper Orthogonal Decomposition (POD) in an under-resolved and marginally-resolved regime, i.e. when the number of modes employed is not enough to capture the system dynamics. We propose a method to re-introduce the contribution of neglected modes through a quadratic correction term, given by the action of a quadratic operator…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Wanda Jackson:
🎵 Funnel Of Love
#WandaJackson
https://wandajackson.bandcamp.com/album/funnel-of-love-whirlpool
https://open.spotify.com/track/6uJXOi796U1D8iW9fj2ZGn

JWST Coronagraphic Images of 14 Her c: a Cold Giant Planet in a Dynamically Hot, Multi-planet System
Daniella C. Bardalez Gagliuffi, William O. Balmer, Laurent Pueyo, Timothy D. Brandt, Mark R. Giovinazzi, Sarah Millholland, Brennen Black, Tiger Lu, Malena Rice, James Mang, Caroline Morley, Brianna Lacy, Julien Girard, Elisabeth Matthews, Aarynn Carter, Brendan P. Bowler, Jacqueline K. Faherty, Clemence Fontanive, Emily Rickman

JWST Coronagraphic Images of 14 Her c: a Cold Giant Planet in a Dynamically Hot, Multi-planet System
Most observed multi-planet systems are coplanar, in a dynamically "cold" configuration of concentric orbits like our own Solar System. With the James Webb Space Telescope (JWST) we have detected 14 Her c, the first mature and cold exoplanet directly imaged in a dynamically "hot", multi-planet system. With large eccentricities and a nonzero mutual inclination, the present-day architecture of this system points to a turbulent past and ongoing angular momentum exchange between the planetary orbits…

Generative Models for Parameter Space Reduction applied to Reduced Order Modelling
Guglielmo Padula, Gianluigi Rozza
https://arxiv.org/abs/2506.09721 https…

Generative Models for Parameter Space Reduction applied to Reduced Order Modelling
Solving and optimising Partial Differential Equations (PDEs) in geometrically parameterised domains often requires iterative methods, leading to high computational and time complexities. One potential solution is to learn a direct mapping from the parameters to the PDE solution. Two prominent methods for this are Data-driven Non-Intrusive Reduced Order Models (DROMs) and Parametrised Physics Informed Neural Networks (PPINNs). However, their accuracy tends to degrade as the number of geometric p…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Loaded Honey:
🎵 Lessons
#LoadedHoney
https://luffone.bandcamp.com/track/loaded-honey-lessons-luffone-remix
https://open.spotify.com/track/2G4Ku71dwuCEKO2gygsM4k

[2025-06-12 Thu (UTC), 6 new articles found for astro-ph.EP Earth and Planetary Astrophysics]
toXiv_bot_toot

Matrix best approximation in the spectral norm
Vance Faber, J\"org Liesen, Petr Tich\'y
https://arxiv.org/abs/2506.09687 https://

Matrix best approximation in the spectral norm
We derive, similar to Lau and Riha, a matrix formulation of a general best approximation theorem of Singer for the special case of spectral approximations of a given matrix from a given subspace. Using our matrix formulation we describe the relation of the spectral approximation problem to semidefinite programming, and we present a simple MATLAB code to solve the problem numerically. We then obtain geometric characterizations of spectral approximations that are based on the $k$-dimensional fiel…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Team Dresch:
🎵 Hand Grenade
#TeamDresch
https://teamdresch.bandcamp.com/album/hand-grenade-2
https://open.spotify.com/track/2fg31sgv1QE8TDeo0TdAVR

Geometric flow regularization in latent spaces for smooth dynamics with the efficient variations of curvature
Andrew Gracyk
https://arxiv.org/abs/2506.09679

Geometric flow regularization in latent spaces for smooth dynamics with the efficient variations of curvature
We design strategies in nonlinear geometric analysis to temper the effects of adversarial learning for sufficiently smooth data of numerical method-type dynamics in encoder-decoder methods, variational and deterministic, through the use of geometric flow regularization. We augment latent spaces with geometric flows to control structure. Our techniques rely on adaptations of curvature and Ricci flow. We invent new geometric flows or discover them neurally and non-parametrically. All of our flows…

Replaced article(s) found for astro-ph.EP. https://arxiv.org/list/astro-ph.EP/new/
[1/1]:
Dynamical Evolution of Planetary Systems
htt…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Heavenly:
🎵 Orange Corduroy Dress
#Heavenly
https://heavenly.bandcamp.com/track/orange-corduroy-dress
https://open.spotify.com/track/5GesvLP2Lh5yFje5VgfwpB

Extensive Database of Spatial Ballistic Captures with Application to Lunar Trailblazer
Lorenzo Ano\`e, Roberto Armellin, Gregory Lantoine, Claudio Bombardelli
https://arxiv.org/abs/2506.09584

Extensive Database of Spatial Ballistic Captures with Application to Lunar Trailblazer
For low-energy missions to the Moon and beyond, Ballistic Capture has proven to be a valuable technique for enabling orbital insertion while alleviating propulsion system requirements. This approach offers two key advantages. First, it extends the insertion window, allowing multiple maneuver opportunities to mitigate potential failures at the nominal insertion point. Second, it enables the required insertion maneuver to be distributed across multiple revolutions, reducing propulsion system cons…

The Gap-Giant Association: Are Planets Hiding in the Gaps?
Caleb Lammers, Joshua N. Winn
https://arxiv.org/abs/2506.10969 https://arx…

The Gap-Giant Association: Are Planets Hiding in the Gaps?
A handful of stars are known to host both an inner system of multiple transiting planets and an outer giant planet. These systems all feature a prominent gap between the orbits of two of the transiting planets, distinguishing them from typical multiplanet systems with more uniform orbital spacings. The reason for the association between inner gaps and outer giants is unknown. In this paper, we assess whether undiscovered planets might occupy these gaps in systems with outer giants. For each of …

🇺🇦 #NowPlaying on KEXP's #VarietyMix
The Cure:
🎵 A Fragile Thing (Twilight Sad remix)
#TheCure
https://open.spotify.com/track/17k0Dwj1nr2VnES26230lJ

Segregated Runge-Kutta schemes for the time integration of the incompressible Navier-Stokes equations in presence of pressure stabilization
Pavel Bakhvalov
https://arxiv.org/abs/2506.09519

Segregated Runge-Kutta schemes for the time integration of the incompressible Navier-Stokes equations in presence of pressure stabilization
Segregated Runge-Kutta (SRK) schemes are time integration methods for the incompressible Navier-Stokes equations. In this approach, convection and diffusion can be independently treated either explicitly or implicitly, which in particular allows to construct implicit-explicit (IMEX) methods. Original SRK schemes (Colomes, Badia, IJNME, 2015) are designed for finite-element methods that satisfy the inf-sup condition. In this paper, the idea of SRK schemes is generalized to spatial discretization…

Self-gravity in thin protoplanetary discs: 1. The smoothing-length approximation versus the exact self-gravity kernel
S. Rendon Restrepo, T. Rometsch, U. Ziegler, O. Gressel
https://arxiv.org/abs/2506.10812

Self-gravity in thin protoplanetary discs: 1. The smoothing-length approximation versus the exact self-gravity kernel
Planet-forming discs often contain structures like spiral arms, typically linked to the disc's gravitational forces. In 2D models, an ad hoc softening prescription is commonly used for self-gravity, but this overlooks the vertical structure's impact, suppresses the Newtonian nature of gravity at short distances and doesn't respect Newton's third law. To address these issues, associated with a Plummer potential approximation, we developed an exact self-gravity kernel for thin, hydrostatically …

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Dark Chisme:
🎵 Breathe, Break it
#DarkChisme
https://darkchisme.bandcamp.com/track/breathe-break-it
https://open.spotify.com/track/0teUZswpRDr8fxEwHW99wZ

FNPF-SEM: A parallel spectral element model in Firedrake for fully nonlinear water wave simulations
Jens Visbech, Anders Melander, Allan Peter Engsig-Karup
https://arxiv.org/abs/2506.09435

FNPF-SEM: A parallel spectral element model in Firedrake for fully nonlinear water wave simulations
We present a new parallel spectral element solver, FNPF-SEM, for simulating linear and fully nonlinear potential flow-based water waves and their interaction with offshore structures. The tool is designed as a general-purpose wave model for offshore engineering applications. Built within the open-source framework Firedrake, the new FNPF-SEM model is designed as a computational tool capable of capturing both linear and nonlinear wave phenomena with high accuracy and efficiency, with support for …

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): XII. Extreme millimetre variability detected in a Class II disc
James M. Miley, Laura M. Perez, Carolina Agurto-Gangas, Anibal Sierra, Leon Trapman, Miguel Vioque, Nicolas Kurtovic, Paola Pinilla, Ilaria Pascucci, Ke Zhang, Rossella Anania, John Carpenter, Lucas A. Cieza, Dingshan Deng, Camilo Gonzalez-Ruilova, Giovanni P. Rosotti, Dary A. Ruiz-Rodriguez, Estephani E. TorresVillanueva

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): XII. Extreme millimetre variability detected in a Class II disc
Variability of millimetre wavelength continuum emission from Class II protoplanetary disks is extremely rare, and when detected it is usually interpreted as originating from non-thermal emission mechanisms that relate to the host star itself rather than its disk. During observations made as part of the AGE-PRO ALMA Large program, significant variability in the brightness of the 2MASS J16202863-2442087 system was detected between individual executions. We report the observed properties of the va…

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Deltron 3030:
🎵 3030
#Deltron3030
https://doktorbagus.bandcamp.com/track/deltron-3030-3030
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Subspace-constrained randomized coordinate descent for linear systems with good low-rank matrix approximations
Jackie Lok, Elizaveta Rebrova
https://arxiv.org/abs/2506.09394

Subspace-constrained randomized coordinate descent for linear systems with good low-rank matrix approximations
The randomized coordinate descent (RCD) method is a classical algorithm with simple, lightweight iterations that is widely used for various optimization problems, including the solution of positive semidefinite linear systems. As a linear solver, RCD is particularly effective when the matrix is well-conditioned; however, its convergence rate deteriorates rapidly in the presence of large spectral outliers. In this paper, we introduce the subspace-constrained randomized coordinate descent (SC-RCD…

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): XI. Beam-corrected gas disk sizes from fitting 12CO moment zero maps
Leon Trapman, Miguel Vioque, Nicol\'as T. Kurtovic, Ke Zhang, Giovanni P. Rosotti, Paola Pinilla, John Carpenter, Lucas A. Cieza, Ilaria Pascucci, Rossella Anania, Carolina Agurto-Gangas, Dingshan Deng, James Miley, Laura M. P\'erez, Anibal Sierra, Beno\^it Tabone, Dary A. Ru\'iz-Rodr\'iguez, Camilo Gonz\'alez-Ruilova, Estephani To…

The ALMA Survey of Gas Evolution of PROtoplanetary Disks (AGE-PRO): XI. Beam-corrected gas disk sizes from fitting 12CO moment zero maps
The inward drift of mm-cm sized pebbles in protoplanetary disks has become an important part of our current theories of planet formation and, more recently, planet composition as well. The gas-to-dust size ratio of protoplanetary disks can provide an important constraint on how pebbles have drifted inward provided that observational effects, especially resolution, can be accounted for. Here we present a method for fitting beam-convolved models to integrated intensity maps of line emission using…

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Benét:
🎵 No Alarm
#Benét
https://benantics.bandcamp.com/track/no-alarm
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Overcoming logarithmic singularities in the Cahn-Hilliard equation with Flory-Huggins potential: An unconditionally convergent ADMM approach
Ruo Li, Shengtong Liang, Zhonghua Qiao
https://arxiv.org/abs/2506.09361

Overcoming logarithmic singularities in the Cahn-Hilliard equation with Flory-Huggins potential: An unconditionally convergent ADMM approach
The Cahn-Hilliard equation with Flory-Huggins potential serves as a fundamental phase field model for describing phase separation phenomena. Due to the presence of logarithmic singularities at $u=\pm 1$, the solution $u$ is constrained within the interval $(-1,1)$. While convex splitting schemes are commonly employed to preserve this bound and guarantee unconditional unique solvability, their practical implementation requires solving nonlinear systems containing singular logarithmic terms at ea…

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Miike Snow:
🎵 Animal (Mark Ronson Remix)
#MiikeSnow
https://maximowastaken.bandcamp.com/track/miike-snow-animal-maximo-tech-house-edit
https://open.spotify.com/track/0X9wubEYVnWE6S4p03ezrx

An Introduction to Solving the Least-Squares Problem in Variational Data Assimilation
I. Dau\v{z}ickait\.e, M. A. Freitag, S. G\"urol, A. S. Lawless, A. Ramage, J. A. Scott, J. M. Tabeart
https://arxiv.org/abs/2506.09211

An Introduction to Solving the Least-Squares Problem in Variational Data Assimilation
Variational data assimilation is a technique for combining measured data with dynamical models. It is a key component of Earth system state estimation and is commonly used in weather and ocean forecasting. The approach involves a large-scale generalized nonlinear least-squares problem. Solving the resulting sequence of sparse linear subproblems requires the use of sophisticated numerical linear algebra methods. In practical applications, the computational demands severely limit the number of it…

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The Jesus and Mary Chain:
🎵 Tower of Song
#TheJesusandMaryChain
https://open.spotify.com/track/6tLF3toLOqEJWqK0hXP0Rh

[2025-06-12 Thu (UTC), 14 new articles found for math.NA Numerical Analysis]
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Placebo:
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Replaced article(s) found for math.NA. https://arxiv.org/list/math.NA/new/
[1/1]:
Coarse spaces for non-symmetric two-level preconditioners based on local extended generalized eig...

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illuminati hotties:
🎵 777
#illuminatihotties
https://illuminatihotties.bandcamp.com/track/777
https://open.spotify.com/track/2LQ4b1UBcrg4APJXQKcXm2

Accelerating Newton-Schulz Iteration for Orthogonalization via Chebyshev-type Polynomials
Ekaterina Grishina, Matvey Smirnov, Maxim Rakhuba
https://arxiv.org/abs/2506.10935

Accelerating Newton-Schulz Iteration for Orthogonalization via Chebyshev-type Polynomials
The problem of computing optimal orthogonal approximation to a given matrix has attracted growing interest in machine learning. Notable applications include the recent Muon optimizer or Riemannian optimization on the Stiefel manifold. Among existing approaches, the Newton-Schulz iteration has emerged as a particularly effective solution, as it relies solely on matrix multiplications and thus achieves high computational efficiency on GPU hardware. Despite its efficiency, the method has inherent …

Numerical approximation of a PDE-constrained Optimization problem that appears in Data-Driven Computational Mechanics
Pedro B. Bazon, Cristian G. Gebhardt, Gustavo C. Buscaglia, Roberto F. Ausas
https://arxiv.org/abs/2506.10894

Numerical approximation of a PDE-constrained Optimization problem that appears in Data-Driven Computational Mechanics
We investigate an optimization problem that arises when working within the paradigm of Data-Driven Computational Mechanics. In the context of the diffusion-reaction problem, such an optimization problem seeks for the continuous primal fields (gradient and flux) that are closest to some predefined discrete fields taken from a material data set. The optimization is performed over primal fields that satisfy the physical conservation law and the geometrical compatibility. We consider a reaction ter…

A Combined Parallel-in-time Direct Inverse (ParaDIn)-Parareal Method for Nonlinear Differential Equations
Subhash Paudel, Nail K. Yamaleev
https://arxiv.org/abs/2506.10820

A Combined Parallel-in-time Direct Inverse (ParaDIn)-Parareal Method for Nonlinear Differential Equations
As has been shown in our previous work, the parallel-in-time direct inverse (ParaDIn) method introduced by Yamaleev and Paudel in (arXiv: 2406.00878v1, 2024) imposes some constraint on the maximum number of time levels, $N_t$, that can be integrated in parallel. To circumvent this problem and further increase the speedup, we combine the ParaDIn method with the Parareal algorithm to efficiently parallelize the first-order time derivative term in nonlinear partial differential equations discretiz…

Reduced-Order Time Splitting for Navier-Stokes with Open Boundaries
Mejdi Aza\"iez, Tom\'as Chac\'on Rebollo, Carlos N\'u\~nez Fern\'andez, Samuele Rubino
https://arxiv.org/abs/2506.10763

Reduced-Order Time Splitting for Navier-Stokes with Open Boundaries
In this work, we propose a Proper Orthogonal Decomposition-Reduced Order Model (POD-ROM) applied to time-splitting schemes for solving the Navier-Stokes equations with open boundary conditions. In this method, we combine three strategies to reduce the computing time to solve NSE: time splitting, reduction of the computational domain through non-standard treatment of open boundary conditions and reduced order modelling. To make the work self-contained, we first present the formulation of the tim…

Semi-discrete moduli of smoothness and their applications in one- and two- sided error estimates
Danilo Costarelli, Donato Lavella
https://arxiv.org/abs/2506.10723

Semi-discrete moduli of smoothness and their applications in one- and two- sided error estimates
In this paper, we introduce a new semi-discrete modulus of smoothness, which generalizes the definition given by Kolomoitsev and Lomako (KL) in 2023 (in the paper published in the J. Approx. Theory), and we establish very general one- and two- sided error estimates under non-restrictive assumptions. The proposed results have been proved exploiting the regularization and approximation properties of certain Steklov integrals introduced by Sendov and Popov in 1983, and differ from the ones given b…

Alternating steepest descent methods for tensor completion with applications to spectromicroscopy
Oliver Townsend, Sergey Dolgov, Silvia Gazzola, Misha Kilmer
https://arxiv.org/abs/2506.10661

Alternating steepest descent methods for tensor completion with applications to spectromicroscopy
In this paper we develop two new Tensor Alternating Steepest Descent algorithms for tensor completion in the low-rank $\star_{M}$-product format, whereby we aim to reconstruct an entire low-rank tensor from a small number of measurements thereof. Both algorithms are rooted in the Alternating Steepest Descent (ASD) method for matrix completion, first proposed in [J. Tanner and K. Wei, Appl. Comput. Harmon. Anal., 40 (2016), pp. 417-429]. In deriving the new methods we target the X-ray spectromic…

Structure and asymptotic preserving deep neural surrogates for uncertainty quantification in multiscale kinetic equations
Wei Chen, Giacomo Dimarco, Lorenzo Pareschi
https://arxiv.org/abs/2506.10636

Structure and asymptotic preserving deep neural surrogates for uncertainty quantification in multiscale kinetic equations
The high dimensionality of kinetic equations with stochastic parameters poses major computational challenges for uncertainty quantification (UQ). Traditional Monte Carlo (MC) sampling methods, while widely used, suffer from slow convergence and high variance, which become increasingly severe as the dimensionality of the parameter space grows. To accelerate MC sampling, we adopt a multiscale control variates strategy that leverages low-fidelity solutions from simplified kinetic models to reduce …

Non-augmented velocity-vorticity-pressure formulation for the Navier--Stokes--Brinkman--Forchheimer problem
Santiago Badia, Carsten Carstensen, Alberto F. Martin, Ricardo Ruiz-Baier, Segundo Villa-Fuentes
https://arxiv.org/abs/2506.10533

Non-augmented velocity-vorticity-pressure formulation for the Navier--Stokes--Brinkman--Forchheimer problem
The flow of incompressible fluid in highly permeable porous media in vorticity - velocity - Bernoulli pressure form leads to a double saddle-point problem in the Navier--Stokes--Brinkman--Forchheimer equations. The paper establishes, for small sources, the existence of solutions on the continuous and discrete level of lowest-order piecewise divergence-free Crouzeix--Raviart finite elements. The vorticity employs a vector version of the pressure space with normal and tangential velocity jump pen…

A semi-Lagrangian scheme for First-Order Mean Field Games based on monotone operators
Elisabetta Carlini, Valentina Coscetti
https://arxiv.org/abs/2506.10509

A semi-Lagrangian scheme for First-Order Mean Field Games based on monotone operators
We construct a semi-Lagrangian scheme for first-order, time-dependent, and non-local Mean Field Games. The convergence of the scheme to a weak solution of the system is analyzed by exploiting a key monotonicity property. To solve the resulting discrete problem, we implement a Learning Value Algorithm, prove its convergence, and propose an acceleration strategy based on a Policy iteration method. Finally, we present numerical experiments that validate the effectiveness of the proposed schemes an…

Convergence of adaptive boundary element methods driven by functional a posteriori error estimates
Alexander Freiszlinger, Dirk Pauly, Dirk Praetorius
https://arxiv.org/abs/2506.10499

Convergence of adaptive boundary element methods driven by functional a posteriori error estimates
The recent work [Kurz et al., Numer. Math., 147 (2021)] proposed functional a posteriori error estimates for boundary element methods (BEMs) together with a related adaptive mesh-refinement strategy. Unlike most a posteriori BEM error estimators, the proposed functional error estimators cover Galerkin as well as collocation BEM and, more importantly, do not control the error in the integral density on the boundary, but the error of the potential approximation in the domain, which is of greater …

Stability analysis of the free-surface Stokes problem and an unconditionally stable explicit scheme
Igor Tominec, Lukas Lundgren, Andr\'e L\"ofgren, Josefin Ahlkrona
https://arxiv.org/abs/2506.10447

Stability analysis of the free-surface Stokes problem and an unconditionally stable explicit scheme
Accurate simulations of ice sheet dynamics, mantle convection, lava flow, and other highly viscous free-surface flows involve solving the coupled Stokes/free-surface equations. In this paper, we theoretically analyze the stability and conservation properties of the weak form of this system for Newtonian fluids and non-Newtonian fluids, at both the continuous and discrete levels. We perform the fully discrete stability analysis for finite element methods used in space with explicit and implicit …

Penalty-Based Feedback Control and Finite Element Analysis for the Stabilization of Nonlinear Reaction-Diffusion Equations
Sudeep Kundu, Shishu pal Singh
https://arxiv.org/abs/2506.10428

Penalty-Based Feedback Control and Finite Element Analysis for the Stabilization of Nonlinear Reaction-Diffusion Equations
In this work, first we employ the penalization technique to analyze the Dirichlet boundary feedback control problem pertaining to reaction-diffusion equation. We establish the stabilization result of the equivalent Robin problem in the \(H^{2}\)-norm with respect to the penalty parameter. Furthermore, we prove that the solution of the penalized control problem converges to the corresponding solution of the Dirichlet boundary feedback control problem as the penalty parameter \(ε\) approaches ze…

Complex scaling for open waveguides
Charles L. Epstein, Tristan Goodwill, Jeremy Hoskins, Solomon Quinn, Manas Rachh
https://arxiv.org/abs/2506.10263 https…

Complex scaling for open waveguides
In this work we analyze the complex scaling method applied to the problem of time-harmonic scalar wave propagation in junctions between `leaky,' or open dielectric waveguides. In [arXiv:2302.04353, arXiv:2310.05816, arXiv:2401.04674, arXiv:2411.11204], it was shown that under suitable assumptions the problem can be reduced to a system of Fredholm second-kind integral equations on an infinite interface, transverse to the waveguides. Here, we show that the kernels appearing in the integral equati…

Enhanced randomized Douglas-Rachford method: Improved probabilities and adaptive momentum
Liqi Guo, Ruike Xiang, Deren Han, Jiaxin Xie
https://arxiv.org/abs/2506.10261

Enhanced randomized Douglas-Rachford method: Improved probabilities and adaptive momentum
Randomized iterative methods have gained recent interest in machine learning and signal processing for solving large-scale linear systems. One such example is the randomized Douglas-Rachford (RDR) method, which updates the iterate by reflecting it through two randomly selected hyperplanes and taking a convex combination with the current point. In this work, we enhance RDR by introducing improved sampling strategies and an adaptive heavy-ball momentum scheme. Specifically, we incorporate without…

Data-driven balanced truncation for second-order systems with generalized proportional damping
Sean Reiter, Steffen W. R. Werner
https://arxiv.org/abs/2506.10118

Data-driven balanced truncation for second-order systems with generalized proportional damping
Structured reduced-order modeling is a central component in the computer-aided design of control systems in which cheap-to-evaluate low-dimensional models with physically meaningful internal structures are computed. In this work, we develop a new approach for the structured data-driven surrogate modeling of linear dynamical systems described by second-order time derivatives via balanced truncation model-order reduction. The proposed method is a data-driven reformulation of position-velocity bal…

[2025-06-13 Fri (UTC), 16 new articles found for math.NA Numerical Analysis]
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