Tootfinder

Domestic Heat Pumps: Barriers to Installation (2022) - A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

Domestic Heat Pumps: Barriers to Installation (2022)
A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

🇺🇦 #NowPlaying on KEXP's #VarietyMix
Essential Logic:
🎵 World Friction
#EssentialLogic
https://essentiallogic.bandcamp.com/track/world-friction
https://open.spotify.com/track/0V3FCyX3XYTPK8bWTex6jN

The Utopia of “AI” is the Dystopia of never being touched by anything.
(Original title: Friction and not being touched)
https://tante.cc/2025/07/30/friction-and-not-being-touched/

Gigantic dynamical spreading and anomalous diffusion of jerky active particles
Hartmut L\"owen
https://arxiv.org/abs/2507.08910 https://

Gigantic dynamical spreading and anomalous diffusion of jerky active particles
Jerky active particles are Brownian self-propelled particles which are dominated by ``jerk'', the change in acceleration. They represent a generalization of inertial active particles. In order to describe jerky active particles, a linear jerk equation of motion which involves a third-order derivative in time, Stokes friction and a spring force is combined with activity modeled by an active Ornstein-Uhlenbeck process. This equation of motion is solved analytically and the associated mean-square …

Superlubricity of Borophene: Tribological Properties in Comparison to hBN
Antoine Hinaut, B. Sena T\"omek\c{c}e, Shuyu Huang, Yiming Song, Ernst Meyer, Antonio Cammarata, Willi Auw\"arter, Thilo Glatzel
https://arxiv.org/abs/2507.07716

Superlubricity of Borophene: Tribological Properties in Comparison to hBN
The tribological performance of 2D materials makes them good candidates toward a reduction of friction at the macroscale. Superlubricity has been observed for graphene, MoS\textsubscript{2} and MXenes and hexagonal boron nitride (hBN) is used to reduce or tune friction, but other materials are investigated as potential candidates for low-lubricity applications. Specifically, borophene is predicted to have ultra-low friction. Here, we experimentally investigate frictional properties of borophene…

Vib2Move: In-Hand Object Reconfiguration via Fingertip Micro-Vibrations
Xili Yi, Nima Fazeli
https://arxiv.org/abs/2506.10923 https://

Vib2Move: In-Hand Object Reconfiguration via Fingertip Micro-Vibrations
We introduce Vib2Move, a novel approach for in-hand object reconfiguration that uses fingertip micro-vibrations and gravity to precisely reposition planar objects. Our framework comprises three key innovations. First, we design a vibration-based actuator that dynamically modulates the effective finger-object friction coefficient, effectively emulating changes in gripping force. Second, we derive a sliding motion model for objects clamped in a parallel gripper with two symmetric, variable-fricti…

Dynamics of low-mass black hole seeds in the BRAHMA simulations using subgrid-dynamical friction: Impact on merger-driven black hole growth in the high redshift Universe
Aklant K. Bhowmick, Laura Blecha, Luke Z. Kelley, Aneesh Sivasankaran, Paul Torrey, Rainer Weinberger, Nianyi Chen, Mark Vogelsberger, Lars Hernquist, Priyamvada Natarajan
https://…

Dynamics of low-mass black hole seeds in the BRAHMA simulations using subgrid-dynamical friction: Impact on merger-driven black hole growth in the high redshift Universe
We analyze the dynamics of low-mass black hole (BH) seeds in the high-redshift ($z\gtrsim5$) Universe using a suite of $[4.5~\mathrm{Mpc}]^3$ and $[9~\mathrm{Mpc}]^3$ BRAHMA cosmological hydrodynamic simulations. The simulations form seeds with mass $M_{\mathrm{seed}}=2.2\times10^3~M_{\odot}$ in halos that exceed critical thresholds of dense & metal-poor gas mass ($5-150~M_{\mathrm{seed}}$) and the halo mass ($1000-10000~M_{\mathrm{seed}}$). While the initial BRAHMA boxes pinned the BHs to the …

🇺🇦 #NowPlaying on KEXP's #SundaySoul
Friction:
🎵 Party
#Friction
https://cardioparty.bandcamp.com/track/friction
https://open.spotify.com/track/6nsOFVX8ZFeDrYcuiPSxPQ

Transition from Continuous to Jumping Solutions in 2D Quasi-static Elastic Contact Problems with Coulomb Friction: the Mathematics Underlying the Onset of Brake Squeal
Patrick Ballard, Flaviana Iurlano
https://arxiv.org/abs/2508.04863

Transition from Continuous to Jumping Solutions in 2D Quasi-static Elastic Contact Problems with Coulomb Friction: the Mathematics Underlying the Onset of Brake Squeal
We formulate the quasi-static elastic contact problem with Coulomb friction in a very general setting, with possible jumps in time for both the load and the solution. Exploiting ideas originating in our recent paper [4], we exhibit an optimal condition on the magnitude of the friction coefficient under which we prove the existence of an absolutely continuous solution for arbitrary absolutely continuous loads in the case of the most general 2D problem. We provide examples showing that, when the …

Adaptive Compensation of Nonlinear Friction in Mechanical Systems Without Velocity Measurement
Jose Guadalupe Romero, Romeo Ortega, Leyan Fang, Alexey Bobtsov
https://arxiv.org/abs/2508.00175

Adaptive Compensation of Nonlinear Friction in Mechanical Systems Without Velocity Measurement
Friction is an unavoidable phenomenon that exists in all mechanical systems incorporating parts with relative motion. It is well-known that friction is a serious impediment for precise servo control, hence the interest to devise a procedure to compensate for it -- a subject that has been studied by many researchers for many years. The vast majority of friction compensation schemes reported in the literature rely on the availability of velocity measurements, an information that is hard to obtain…

Hapster: Using Apple Watch Haptics to Enable Live Low-Friction Student Feedback in the Physical Classroom
Oleg Aleksandrovich Golev, Michelle Huang, Chanketya Nop, Kritin Vongthongsri, Andr\'es Monroy-Hern\'andez, Parastoo Abtahi
https://arxiv.org/abs/2507.05605

Hapster: Using Apple Watch Haptics to Enable Live Low-Friction Student Feedback in the Physical Classroom
The benefits of student response systems (SRSs) for in-person lectures are well-researched. However, all current SRSs only rely on a visual interface to relay information to the instructor. We describe the design and evaluation of Hapster, a prototype system that uses an Apple Watch to deliver live, aggregated student feedback to the instructor via both visual and vibro-tactile modalities. We evaluated this system with 6 instructors and 155 students at a U.S. university. Participants reported t…

Bayesian optimization of a cost function in suboptimal control for reducing skin friction drag in wall turbulence
Yusuke Yugeta, Yosuke Hasegawa
https://arxiv.org/abs/2507.04654

Bayesian optimization of a cost function in suboptimal control for reducing skin friction drag in wall turbulence
A systematic and automated framework for developing closed-loop flow control strategies is proposed, integrating suboptimal control theory [Lee et al., J. Fluid Mech. 358, 245 (1998)] with Bayesian optimization. The approach is demonstrated in the context of reducing skin friction drag in a low-Reynolds-number turbulent channel flow. A cost function in the suboptimal control framework is formulated as a linear combination of various wall quantities, with the corresponding weight coefficients op…

I wrote about frictionlessness and "AI". The essay is admittedly a bit of a weird ride trying to connect a few very distinct thoughts. I hope it's still worth reading.
https://tante.cc/2025/07/30/friction-and-not-being-touched/

Friction and not being touched
The journalist Karen Hao – who published an absolutely fantastic book about OpenAI called “Empire of AI” recently – coined (as far as I know) one of the best terms for describing modern “AI” systems: Everything Machines. “AI” systems are not framed as specific tools that solve specific problems in specific ways but just as […]

Unequal Uncertainty: Rethinking Algorithmic Interventions for Mitigating Discrimination from AI
Holli Sargeant, Mackenzie Jorgensen, Arina Shah, Adrian Weller, Umang Bhatt
https://arxiv.org/abs/2508.07872

Unequal Uncertainty: Rethinking Algorithmic Interventions for Mitigating Discrimination from AI
Uncertainty in artificial intelligence (AI) predictions poses urgent legal and ethical challenges for AI-assisted decision-making. We examine two algorithmic interventions that act as guardrails for human-AI collaboration: selective abstention, which withholds high-uncertainty predictions from human decision-makers, and selective friction, which delivers those predictions together with salient warnings or disclosures that slow the decision process. Research has shown that selective abstention b…

Detectability of compact intermediate-mass black hole binaries as low-frequency gravitational wave sources: the influence of dynamical friction of dark matter
Wen-Qing Jia, Wen-Cong Chen
https://arxiv.org/abs/2508.03582

Detectability of compact intermediate-mass black hole binaries as low-frequency gravitational wave sources: the influence of dynamical friction of dark matter
The black hole (BH) spin could significantly change the density of dark matter (DM) in its vicinity, creating a mini-spike of the density of DM. The dynamical friction (DF) between DM and the companion star of a BH can provide an efficient loss of angular momentum, driving the BH-main sequence (MS) star binary to evolve toward a compact orbit system. We investigate the influence of the DF of DM on the detectability of intermediate-mass black hole (IMBH)-MS binaries as low-frequency gravitationa…

Domestic Heat Pumps: Barriers to Installation (2022) - A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

Domestic Heat Pumps: Barriers to Installation (2022)
A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

The disappearance of the unclear question: AI speeds up research, but without friction, do students lose the deep thinking that turns bad questions into meaningful learning? https://www.unesco.org/en/articles/disappearance-unclear-question

The disappearance of the unclear question
AI speeds up research, but without friction, do students lose the deep thinking that turns bad questions into meaningful learning?

"We're becoming the soft, floating people from Wall-E. Ordering everything to our doorstep, swiping instead of talking, letting AI write our emails and create our art. Convenience is stealing everything from us if we let it. The friction is where the growth happens. The resistance is where we build strength. Work, real work, will give us fulfillment in ways we never expected, in ways that all the optimization hacks and life shortcuts never could."

why are we lying to young people about work?
hard work isn't the tax you pay for living, it's the tuition for a life worth having -your fav gen z philosopher x

Since DJV went into a hiatus, I have tried #mrv2 more than once but it wouldn't do. Brought down my whole Linux desktop last time I tried, just by showing/hiding certain parts of the GUI.
So I've compiled #OpenRV but I really want something that loads faster than that clunky old player (even…

First Contact: Data-driven Friction-Stir Process Control
James Koch, Ethan King, WoongJo Choi, Megan Ebers, David Garcia, Ken Ross, Keerti Kappagantula
https://arxiv.org/abs/2507.03177

First Contact: Data-driven Friction-Stir Process Control
This study validates the use of Neural Lumped Parameter Differential Equations for open-loop setpoint control of the plunge sequence in Friction Stir Processing (FSP). The approach integrates a data-driven framework with classical heat transfer techniques to predict tool temperatures, informing control strategies. By utilizing a trained Neural Lumped Parameter Differential Equation model, we translate theoretical predictions into practical set-point control, facilitating rapid attainment of des…

"Fuck the algorithms. Principle, integrity, naiveté... call it what you will. They don't care – we do." Ana in Cyberpunk 2077
Empathy and mutual care is part of the friction that AI and other automation tech rationalizes away.

Yes, yes, yes, yes, @…! 👏
“For now, I’m planning on continuing to roll up my sleeves. I want to make things because I’m human and alive. I want to go on journeys and grow. I’m not always looking for an easy path, I want the friction. Because if I give up the journey, what am I really making? What do I actually learn?”

Agency Among Agents: Designing with Hypertextual Friction in the Algorithmic Web
Sophia Liu, Shm Garanganao Almeda
https://arxiv.org/abs/2507.23585 https://

Agency Among Agents: Designing with Hypertextual Friction in the Algorithmic Web
Today's algorithm-driven interfaces, from recommendation feeds to GenAI tools, often prioritize engagement and efficiency at the expense of user agency. As systems take on more decision-making, users have less control over what they see and how meaning or relationships between content are constructed. This paper introduces "Hypertextual Friction," a conceptual design stance that repositions classical hypertext principles--friction, traceability, and structure--as actionable values for reclaimin…

Impact of friction force and retrieval speed on in silico mechanical thrombectomies: a sensitivity analysis
Mahesh S. Nagargoje, Virginia Fregona, Giulia Luraghi, Francesco Migliavacca, Demitria A Poulos, Bryan C Good, Jose Felix Rodriguez Matas
https://arxiv.org/abs/2506.03812

Impact of friction force and retrieval speed on in silico mechanical thrombectomies: a sensitivity analysis
Background: Mechanical Thrombectomy (MT) is a widely accepted first-line treatment for Acute Ischemic Stroke (AIS) and it has been studied using in vitro and in silico models. Thrombectomy outcomes have been performed for patient-specific cases using in silico models. However, until now, in vivo friction coefficients for stent-vessel, stent-clot, and clot-vessel interactions are unknown, but in vitro experiments have been attempted with significant standard deviations. These interactions and fr…

🇺🇦 Auf radioeins läuft...
DJ Friction:
🎵 Could Heaven Ever Be Like This
#NowPlaying #DJFriction
https://open.spotify.com/track/4eOOrfLqTnbO6fUz7ACKDY

This https://arxiv.org/abs/2303.03489 has been replaced.
link: https://scholar.google.com/scholar?q=a

Large time behavior for the 3D Navier-Stokes with Navier boundary conditions
We study the three-dimensional incompressible Navier-Stokes equations in a smooth bounded domain $Ω$ with initial velocity $u_0$ square-integrable, divergence-free and tangent to $\partial Ω$. We supplement the equations with the Navier friction boundary conditions $u \cdot n = 0$ and $[(2Su)n + αu]_{tang} = 0$, where $n$ is the unit exterior normal to $\partial Ω$, $Su = (Du + (Du)^t)/2$, $α\in C^0(\partialΩ)$ is the boundary friction coefficient and $[\cdot]_{tang}$ is the projection of…

Mass loss and dynamical friction on the Fornax dSph galaxy in the Milky Way potential
Pierfrancesco Di Cintio, Giuliano Iorio, Carlo Nipoti, Francesco Calura
https://arxiv.org/abs/2508.03286

Mass loss and dynamical friction on the Fornax dSph galaxy in the Milky Way potential
We study the interplay between mass-loss and dynamical friction (DF) on the orbital decay of the Fornax dwarf spheroidal galaxy in the potential of the Milky Way (MW). Using a simplified single particle approach combined with a mass-loss rate extrapolated by $N-$body simulations we find that the the effect of a time-dependent mass partially compensates DF, and typically produces a much less evident decay of the pergalactic distance, thus confirming that $N-$body simulations in smooth MW potenti…

AI Magnetic Levitation (Maglev) Conveyor for Automated Assembly Production
Ray Wai Man Kong
https://arxiv.org/abs/2506.08039 https://…

AI Magnetic Levitation (Maglev) Conveyor for Automated Assembly Production
Efficiency, speed, and precision are essential in modern manufacturing. AI Maglev Conveyor system, combining magnetic levitation (maglev) technology with artificial intelligence (AI), revolutionizes automated production processes. This system reduces maintenance costs and downtime by eliminating friction, enhancing operational efficiency. It transports goods swiftly with minimal energy consumption, optimizing resource use and supporting sustainability. AI integration enables real-time monitorin…

Mean velocity profiles and total shear stress profiles in adverse-pressure-gradient turbulent boundary layers considering history effect
Zhengqin Shu, Chunxiao Xu
https://arxiv.org/abs/2508.07663

Mean velocity profiles and total shear stress profiles in adverse-pressure-gradient turbulent boundary layers considering history effect
This study focuses on developing a predictive model for mean velocity profiles and total shear stress profiles in turbulent boundary layers subjected to adverse pressure gradients, especially with history effects. Based on universal near-wall similarity, a new scaling using friction velocity modified by Clauser pressure gradient parameter is introduced to restore streamwise self-similarity. Furthermore, an estimation-correction model is developed, explicitly incorporating a streamwise derivativ…

Dissipative response of driven bead-spring-dashpot chains
R. Kailasham
https://arxiv.org/abs/2507.05692 https://arxiv.org/pdf/2507.05…

Dissipative response of driven bead-spring-dashpot chains
The work dissipated in pulling a polymer chain with internal friction is numerically calculated by considering a sequence of $N$ bead-spring-dashpots tethered at one end and being pulled at the other using a harmonic trap via linear and symmetric protocols. The variation of the dissipation with the chain length, pulling trap stiffness, and the internal friction parameter are examined in detail for both the protocols. In the limit of high trap stiffness: (i) the dissipation $decreases$ with $N$ …

Domestic Heat Pumps: Barriers to Installation (2022) - A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

Domestic Heat Pumps: Barriers to Installation (2022)
A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

OpenLambdaVerse: A Dataset and Analysis of Open-Source Serverless Applications
Angel C. Chavez-Moreno, Cristina L. Abad
https://arxiv.org/abs/2508.01492 https://

OpenLambdaVerse: A Dataset and Analysis of Open-Source Serverless Applications
Function-as-a-Service (FaaS) is at the core of serverless computing, enabling developers to easily deploy applications without managing computing resources. With an Infrastructure-as-Code (IaC) approach, frameworks like the Serverless Framework use YAML configurations to define and deploy APIs, tasks, workflows, and event-driven applications on cloud providers, promoting zero-friction development. As with any rapidly evolving ecosystem, there is a need for updated insights into how these tools …

Relativistic scalar dark matter drag forces on a black hole binary
Shuo Xin, Elias R. Most
https://arxiv.org/abs/2507.18934 https://arxiv.org/pdf/2507.1893…

Relativistic scalar dark matter drag forces on a black hole binary
Dark matter around black holes can induce drag forces through dynamical friction and accretion, potentially affecting the orbital evolution and gravitational wave emission of binary systems. While dynamical friction from scalar field dark matter has been studied in the relativistic regime for single black holes, the case of a binary black hole (BBH) has remained unexplored. As a first step, we present a series of two-dimensional general-relativistic simulations of BBH in a wind tunnel for an as…

3D Steering and Localization in Pipes and Burrows using an Externally Steered Soft Growing Robot
Yimeng Qin, Jared Grinberg, William Heap, Allison M. Okamura
https://arxiv.org/abs/2507.07225

3D Steering and Localization in Pipes and Burrows using an Externally Steered Soft Growing Robot
Navigation and inspection in confined environments, such as tunnels and pipes, pose significant challenges for existing robots due to limitations in maneuverability and adaptability to varying geometries. Vine robots, which are soft growing continuum robots that extend their length through soft material eversion at their tip, offer unique advantages due to their ability to navigate tight spaces, adapt to complex paths, and minimize friction. However, existing vine robot designs struggle with na…

@… @… Very very cool! 🌟
Do you happen to release / sell your animations for people to remix (like in the Pling KDE store), or do tutorials?
I'm glad there's now documentation for Friction, but I had trouble…

Mixed Finite Element Method for a Hemivariational Inequality of Stationary convective Brinkman-Forchheimer Extended Darcy equations
Wasim Akram, Manil T. Mohan
https://arxiv.org/abs/2508.02797

Mixed Finite Element Method for a Hemivariational Inequality of Stationary convective Brinkman-Forchheimer Extended Darcy equations
This paper presents the formulation and analysis of a mixed finite element method for a hemivariational inequality arising from the stationary convective Brinkman-Forchheimer extended Darcy (CBFeD) equations. This model extends the incompressible Navier-Stokes equations by incorporating both damping and pumping effects. The hemivariational inequality describes the flow of a viscous, incompressible fluid through a saturated porous medium, subject to a nonsmooth, nonconvex friction-type slip boun…

Replaced article(s) found for cond-mat.soft. https://arxiv.org/list/cond-mat.soft/new
[1/1]:
- Attraction-enhanced emergence of friction in colloidal matter
Berend van der Meer, Taiki Yanagishima, Roel P. A. Dullens

Due to a recent post about #friction I've found out about #cinelinux.
Looks like a bilingual Brazilian blog/forum about #VFX and related topics and software solutions on Linux!
They aren'…

This https://arxiv.org/abs/2504.08884 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_…

The role of wind asphericity in dynamical friction
Dynamical friction (DF) may affect the dynamics of stars moving through dense media. This is the case for stars and compact objects (COs) crossing active galactic nuclei (AGN) discs, stellar clusters, and common envelopes (CE), driving stellar migration. DF may decelerate the moving stellar object and may also, under certain conditions, produce an acceleration. In this paper, we study the DF and its effects in the interaction between a star and the ambient gaseous medium through a set of two-di…

Donald Trump’s attempt to take credit for the additional weapons headed to Ukraine at Europe’s expense has created some friction in EU-US relations.
“If we pay for these weapons, it’s our support,”
said Kaja Kallas, the EU foreign policy chief, on Wednesday.
“So it’s European support,
and we are doing as much as we can to help Ukraine …
If you promise to give the weapons but say that somebody else is going to pay for it,
it’s not really given by …

Static vs dynamic rough energy landscapes: Where is diffusion faster?
Dmitrii E. Makarov, Peter Sollich
https://arxiv.org/abs/2506.02195 https://

Static vs dynamic rough energy landscapes: Where is diffusion faster?
Molecules in dense environments, such as biological cells, are subjected to forces that fluctuate both in time and in space. While spatial fluctuations are captured by Lifson-Jackson-Zwanzig's model of "diffusion in a rough potential", and temporal fluctuations are often viewed as leading to additional friction effects, a unified view where the environment fluctuates both in time and in space is currently lacking. Here we introduce a discrete-state model of a landscape fluctuating both in time …

Effect of crystallinity on the frictional and wear performance of molybdenum disulfide: A molecular dynamics study
Abhiram B R, Ilia Ponomarev, Tomas Polcar
https://arxiv.org/abs/2506.00690

Effect of crystallinity on the frictional and wear performance of molybdenum disulfide: A molecular dynamics study
The frictional and wear performance of molybdenum disulfide (MoS2) is significantly influenced by its intrinsic arrangement of crystals or crystallinity. In this study, we investigate the effect of crystallinty on coefficient of friction (COF) and wear in MoS2 using a suite of reactive molecular dynamics (MD) simulations. A range of configurations, from amorphous to crystalline, is modeled to capture the effect of structural order on the tribological behavior. To study friction and wear, we sim…

<https://www.theregister.com/2025/07/23/opinion_column_starlink_interference/>
# Musk is messing with the Cosmic Dawn. Will alien hunters save the day for all mankind?
## Science friction at the far end of time for SpaceX and astronomy

Evolution models with time-dependent coefficients in friction and viscoelastic damping terms
Halit Sevki Aslan
https://arxiv.org/abs/2506.24058 https://

Evolution models with time-dependent coefficients in friction and viscoelastic damping terms
We study the following Cauchy problem for the linear wave equation with both time-dependent friction and time-dependent viscoelastic damping: \begin{equation} \label{EqAbstract}\tag{$\ast$} \begin{cases} u_{tt}- Δu + b(t)u_t - g(t)Δu_t=0, &(t,x) \in (0,\infty) \times \mathbb{R}^n, \\ u(0,x)= u_0(x),\quad u_t(0,x)= u_1(x), &x \in \mathbb{R}^n. \end{cases} \end{equation} Our goal is to derive decay estimates for higher order energy norms of solutions to this problem. We focus on the interplay b…

Domestic Heat Pumps: Barriers to Installation (2022) - A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

Domestic Heat Pumps: Barriers to Installation (2022)
A case study in the friction in specifying and installing a heat-pump in the UK, even for a savvy early adopter. #heatpump #netZero #futureReady

On the interaction of dilatancy and friction in the behavior of fluid-saturated sheared granular materials: a coupled Computational Fluid Dynamics--Discrete Element Method study
Bimal Chhushyabaga (Department of Civil,Environmental Engineering, University of Houston), Behrooz Ferdowsi (Department of Civil,Environmental Engineering, University of Houston)
https:…

On the interaction of dilatancy and friction in the behavior of fluid-saturated sheared granular materials: a coupled Computational Fluid Dynamics--Discrete Element Method study
Frictional instabilities in fluid-saturated granular materials underlie critical natural hazards such as submarine landslides and earthquake initiation. Distinct failure behaviors emerge under subaerial and subaqueous conditions due to the coupled effects of mechanical deformation, interparticle friction, and fluid interactions. This study employs three-dimensional coupled Computational Fluid Dynamics-Discrete Element Method (CFD-DEM) simulations to investigate the collapse and runout dynamics …

Discrete Element Parameter Calibration of Livestock Salt Based on Particle Scaling
Lulu Nie, Baoqin Wen, Jingbin Li, Shufeng Li, Yali Li, Zhaokun Zhang, Zhiyuan Wang, Zhihao Fan
https://arxiv.org/abs/2506.03786

Discrete Element Parameter Calibration of Livestock Salt Based on Particle Scaling
In order to obtain accurate contact parameters for the discrete element simulation of salt particles used in animal husbandry, the principle of particle contact scaling and dimensional analysis were used for particle scaling. Firstly, the Plackett Burman experiment was used to screen the parameters that significantly affect the angle of repose: salt salt rolling friction coefficient, salt salt recovery coefficient, and salt steel rolling friction coefficient. Considering the influence of other …

This https://arxiv.org/abs/2501.03542 has been replaced.
initial toot: https://mastoxiv.page/@ar…

Turbulence modeling over riblets via domain transformation
Numerical and experimental studies have demonstrated the drag-reducing potential of carefully designed streamwise-elongated riblets in lowering skin-friction drag. To support the systematic design of such surface corrugations, recent efforts have integrated simplified versions of the governing equations with innovative methods for representing the effects of rough boundaries on flow dynamics. Notably, the statistical response of the eddy-viscosity-enhanced linearized Navier-Stokes equations has…

Molecular Dynamics Simulations of Nanoscale Friction on Illite Clay: Effects of Solvent Salt Ions and Electric Double Layer
Ge Li, Astrid S. de Wijn
https://arxiv.org/abs/2507.14158

Molecular Dynamics Simulations of Nanoscale Friction on Illite Clay: Effects of Solvent Salt Ions and Electric Double Layer
Quick clay is a highly sensitive soil that transforms rapidly from solid to liquid under minor stress, as a result of long-term salt leaching that drastically reduces shear strength. Stabilizing it is both costly and carbon-intensive, significantly impacting construction emissions in regions like Norway. Developing greener stabilization methods is challenging due to limited understanding of the weakening mechanisms and the specific roles of different salts. In this study, we use molecular dynam…

TinyDEM: Minimal open granular DEM code with sliding, rolling and twisting friction
Roman Vetter
https://arxiv.org/abs/2507.12610 https://

TinyDEM: Minimal open granular DEM code with sliding, rolling and twisting friction
This article introduces TinyDEM, a lightweight implementation of a full-fledged discrete element method (DEM) solver in 3D. Newton's damped equations of motion are solved explicitly for translations and rotations of a polydisperse ensemble of dry, soft, granular spherical particles, using quaternions to represent their orientation in space without gimbal lock. Particle collisions are modeled as inelastic and frictional, including full exchange of torque. With a general particle-mesh collision r…

fun #chinafake fact: many believe that http://www.eptoys.net is short for “ever profit toys”, but it actually stands for “eepy toys” @…

SCCRUB: Surface Cleaning Compliant Robot Utilizing Bristles
Jakub F. Kowalewski, Keeyon Hajjafar, Alyssa Ugent, Jeffrey Ian Lipton
https://arxiv.org/abs/2507.06053

SCCRUB: Surface Cleaning Compliant Robot Utilizing Bristles
Scrubbing surfaces is a physically demanding and time-intensive task. Removing adhered contamination requires substantial friction generated through pressure and torque or high lateral forces. Rigid robotic manipulators, while capable of exerting these forces, are usually confined to structured environments isolated from humans due to safety risks. In contrast, soft robot arms can safely work around humans and adapt to environmental uncertainty, but typically struggle to transmit the continuous…

Rotational Dynamics of ATP Synthase: Mechanical Constraints and Energy Dissipative Channels
Islam K. Matar, Peyman Fahimi, Cherif F. Matta
https://arxiv.org/abs/2506.23439

Rotational Dynamics of ATP Synthase: Mechanical Constraints and Energy Dissipative Channels
The proton motive force (PMF) across the inner mitochondrial membrane delivers approximately 0.2 eV of energy per proton, powering the FoF1-ATP synthase molecular motor. Here, we provide a detailed accounting of how this energy is utilized: Approximately 75-83% is transduced into the chemical free energy of ATP synthesis, while the remaining 17-25% is dissipated through internal friction, viscous drag, proton leakage, electroviscous effects, elastic deformations, and information-theoretic costs…

Dynamical friction and massive black hole orbits: analytical predictions and numerical solutions
Alice Damiano, Stefano Borgani, Milena Valentini, Giuseppe Murante, Luca Tornatore, Petr Strakos, Milan Jaros
https://arxiv.org/abs/2506.20740

Dynamical friction and massive black hole orbits: analytical predictions and numerical solutions
We investigate the orbital decay of a massive BH embedded in a dark matter halo and a stellar bulge, using both analytical and numerical simulations with the aim of developing and validating a reliable dynamical friction (DF) correction across simulation resolutions. We develop a Python-based library to solve the equations of motion of the BH and provide an analytical framework for the numerical results. Then, we carry out simulations at different resolutions and for different softening choices…

Shear flow of frictional spheroids: lentil-like grains slide more than rice-like
Jacopo Bilotto, Martin Trulsson, Jean-Fran\c{c}ois Molinari
https://arxiv.org/abs/2507.04429

Shear flow of frictional spheroids: lentil-like grains slide more than rice-like
The rheology of dense granular shear flows is influenced by friction and particle shape. We investigate numerically the impact of non-spherical particle geometries under shear on packing fraction, stress ratios, velocity fluctuations, force distribution, and dissipation mechanisms, for a wide range of inertial numbers, friction coefficients and aspect ratios. We obtain a regime diagram for the dissipation which shows that lentil-like (oblate) particles exhibit an extended sliding regime compare…

Fast magneto-acoustic waves in the solar chromosphere: Comparison of single-fluid and two-fluid approximations
M. M. G\'omez M\'iguez, D. Mart\'inez-G\'omez, E. Khomenko, B. Popescu Braileanu, M. Collados, P. S. Cally
https://arxiv.org/abs/2507.16460

Fast magneto-acoustic waves in the solar chromosphere: Comparison of single-fluid and two-fluid approximations
Context: The mechanism behind the heating of the solar chromosphere remains unclear. Friction between neutrals and charges is expected to contribute to plasma heating in a partially ionised plasma (PIP). Aims: We aim to study the efficiency of the frictional heating mechanism in partially ionised plasmas by comparing a single-fluid model (1F) using ambipolar diffusion and a two-fluid model (2F) that incorporates elastic collision terms. Methods: We use the code MANCHA-2F to solve the equations …

Self-Interacting Dark-Matter Spikes and the Final-Parsec Problem: Bayesian constraints from the NANOGrav 15-Year Gravitational-Wave Background
Shreyas Tiruvaskar, Chris Gordon
https://arxiv.org/abs/2506.18153

Self-Interacting Dark-Matter Spikes and the Final-Parsec Problem: Bayesian constraints from the NANOGrav 15-Year Gravitational-Wave Background
A self-interacting dark-matter (SIDM) density spike around merging supermassive black holes (SMBHs) may be able to supply the dynamical friction needed to shrink binaries from $\sim 1\, \mathrm{pc}$ to $\sim 10^{-2} \,\mathrm{pc}$, thereby resolving the long-standing ``final-parsec problem.'' Embedding the binary-halo system in a cosmological population model, we evolve the inspiral under the combined influence of gravitational-wave (GW) emission and SIDM drag, compute the resulting nanohertz G…

Magneto-radiative modelling and artificial neural network optimization of biofluid flow in a stenosed arterial domain
S P Shivakumar, Gunisetty Ramasekhar, P Nimmy, Sujesh Areekara, L Thanuja, T V Smitha, S Devanathan, Ganesh R Naik, K V Nagaraja
https://arxiv.org/abs/2507.06273

Magneto-radiative modelling and artificial neural network optimization of biofluid flow in a stenosed arterial domain
The increasing complexity of cardiovascular diseases and limitations in traditional healing methods mandate the invention of new drug delivery systems that assure targeted, effective, and regulated treatments, contributing directly to UN SDGs 3 and 9, thereby encouraging the utilization of sustainable medical technologies in healthcare. This study investigates the flow of a Casson-Maxwell nanofluid through a stenosed arterial domain. The quantities, such as skin friction and heat transfer rate,…

Muon-induced fission as a probe of the underlying dynamics in nuclear fission
Christian Ross, A. S. Umar
https://arxiv.org/abs/2507.02191 https://

Muon-induced fission as a probe of the underlying dynamics in nuclear fission
Muon-induced fission could be utilized as a probe to study the underlying dynamics of nuclear fission. The probability of muon attachment to the light asymmetric fission fragment is sensitive to fission dynamics, such as the timescale and friction of the fission event, charge asymmetry, and possibly the shape of the fission fragments. We focus on muonic atoms that are formed with actinide nuclei. A relativistic approach is employed, solving the Dirac equation for the muonic wavefunction in the …

TL;DR:🧵
Today I lost 2 hours because TypeORM ESM NestJS is a fragile combo when it comes to migrations.
No migration:status.
No ESM-compatible CLI.
No schema awareness.
Class name must match filename (with timestamp!).
So I wrote my own migration-status.ts script to compare database state with the migration folder.
Lesson: if you need INSERT INTO "schema"."table", don’t forget the schema.
ORMs give you boilerplate — and tra…

Day#10 Migrations vs Developer: A story of friction
Today was supposed to be a calm day. I just wanted to add a single value to a lookup table using a TypeORM migration. Two hours later, I ...

Subdiffusion from competition between multi-exponential friction memory and energy barriers
Anton Klimek, Benjamin A. Dalton, Roland R. Netz
https://arxiv.org/abs/2506.03036

Subdiffusion from competition between multi-exponential friction memory and energy barriers
Subdiffusion is a hallmark of complex systems, ranging from protein folding to transport in viscoelastic media. However, despite its pervasiveness, the mechanistic origins of subdiffusion remain contested. Here, we analyze both Markovian and non-Markovian dynamics, in the presence and absence of energy barriers, in order to disentangle the distinct contributions of memory-dependent friction and energy barriers to the emergence of subdiffusive behavior. Focusing on the mean squared displacement …

Geoff: The Generic Optimization Framework & Frontend for Particle Accelerator Controls
Penelope Madysa, Sabrina Appel, Verena Kain, Michael Schenk
https://arxiv.org/abs/2506.03796

Geoff: The Generic Optimization Framework & Frontend for Particle Accelerator Controls
Geoff is a collection of Python packages that form a framework for automation of particle accelerator controls. With particle accelerator laboratories around the world researching machine learning techniques to improve accelerator performance and uptime, a multitude of approaches and algorithms have emerged. The purpose of Geoff is to harmonize these approaches and to minimize friction when comparing or migrating between them. It provides standardized interfaces for optimization problems, utili…

Democracies should stop focusing on efficiency: Lack thereof and friction are important parts of what defines a healthy democracy. Efficiency will always sacrifice participation, representation and meaningful political discourse. The focus on it is a path into authoritarianism. In the essay ...

Muffled Murmurs: Environmental effects in the LISA stochastic signal from stellar-mass black hole binaries
Ran Chen, Rohit S. Chandramouli, Federico Pozzoli, Riccardo Buscicchio, Enrico Barausse
https://arxiv.org/abs/2507.00694

Muffled Murmurs: Environmental effects in the LISA stochastic signal from stellar-mass black hole binaries
The population of unresolved stellar-mass black hole binaries (sBBHs) is expected to produce a stochastic gravitational-wave background (SGWB) potentially detectable by the Laser Interferometer Space Antenna (LISA). In this work, we compute the imprint of astrophysical environmental effect--such as gas dynamical friction and accretion--on this background. Using the sBBHs population constraints obtained by the LIGO--Virgo--Kagra collaboration, we compute the expected SGWB and develop a phenomeno…

Heavy-ball dynamics with Hessian-driven damping for non-convex optimization under the {\L}ojasiewicz condition
Vassilis Apidopoulos, Vasiliki Mavrogeorgou, Theodoros G. Tsironis
https://arxiv.org/abs/2506.11705

Heavy-ball dynamics with Hessian-driven damping for non-convex optimization under the Łojasiewicz condition
In this paper, we examine the convergence properties of heavy-ball dynamics with Hessian-driven damping in smooth non-convex optimization problems satisfying a Łojasiewicz condition. In this general setting, we provide a series of tight, worst-case optimal convergence rate guarantees as a function of the dynamics' friction coefficients and the Łojasiewicz exponent of the problem's objective function. Importantly, the linear rates that we obtain improve on previous available rates and they sug…

Nonlocal current-driven heat flow in ideal plasmas
Nicholas Mitchell, David Chapman, Grigory Kagan
https://arxiv.org/abs/2507.18430 https://arxiv.org/pdf/2…

Nonlocal current-driven heat flow in ideal plasmas
Electron heat flux is an important and often dominant mechanism of energy transport in a variety of collisional plasmas in a confined fusion or astrophysical context. While nonlocal conductive heat transport, driven by strong temperature gradients, has been investigated extensively in previous literature, nonlocal regimes of the current-driven heat flow and friction have not received the same attention. In this work, a first-principles reduced kinetic method (RKM) is applied to study nonlocal e…

Evolving Neural Controllers for Xpilot-AI Racing Using Neuroevolution of Augmenting Topologies
Jim O'Connor, Nicholas Lorentzen, Gary B. Parker, Derin Gezgin
https://arxiv.org/abs/2507.13549

Evolving Neural Controllers for Xpilot-AI Racing Using Neuroevolution of Augmenting Topologies
This paper investigates the development of high-performance racing controllers for a newly implemented racing mode within the Xpilot-AI platform, utilizing the Neuro Evolution of Augmenting Topologies (NEAT) algorithm. By leveraging NEAT's capability to evolve both the structure and weights of neural networks, we develop adaptive controllers that can navigate complex circuits under the challenging space simulation physics of Xpilot-AI, which includes elements such as inertia, friction, and grav…

On the edge of complexity: The simplest not simple coupled mechanical system
Gergely Nyitray
https://arxiv.org/abs/2508.01379 https://arxiv.org/pdf/2508.01…

On the edge of complexity: The simplest not simple coupled mechanical system
We show that during normal modes of an oscillatory system consisting of a hoop and a cylinder joining their centers by an ideal spring, its central mass does not remain at rest. This effect is due to the resultant external static friction forces acting on the system which disappears when the coupled rigid bodies have the same moment of inertia. However, in case of different moment of inertia by proper positioning the two fixed end points of the spring vertically, it is shown that the central ma…

Replaced article(s) found for cond-mat.quant-gas. https://arxiv.org/list/cond-mat.quant-gas/new
[1/1]:
- Mutual friction and vortex Hall angle in a strongly interacting Fermi superfluid
Nicola Grani, et al.

When Domains Collide: An Activity Theory Exploration of Cross-Disciplinary Collaboration
Zixuan Feng, Thomas Zimmermann, Lorenzo Pisani, Christopher Gooley, Jeremiah Wander, Anita Sarma
https://arxiv.org/abs/2506.20063

When Domains Collide: An Activity Theory Exploration of Cross-Disciplinary Collaboration
Background: Software development teams are increasingly diverse, embedded, and cross-disciplinary. Domain experts (DEs) from different disciplines collaborate with professional software developers (SDEs), bringing complementary expertise in creating and maintaining complex production software. However, contested expectations, divergent problem-solving perspectives, and conflicting priorities lead to friction. Aims: This study aims to investigate the dynamics of emerging collaboration of cross-d…

Disentangling temperature and Reynolds number effects in quantum turbulence
Juan Ignacio Polanco, Philippe-E. Roche, Luminita Danaila, Emmanuel L\'ev\^eque
https://arxiv.org/abs/2507.03357

Disentangling temperature and Reynolds number effects in quantum turbulence
The interplay between viscous and frictional dissipation is key to understanding quantum turbulence dynamics in superfluid $^4$He. Based on a coarse-grained two-fluid description, an original scale-by-scale energy budget that identifies each scale's contribution to energy dissipation is derived. Using the Hall-Vinen-Bekharevich-Khalatnikov (HVBK) model to further characterize mutual friction, direct numerical simulations at temperatures $1.44 \, \mathrm{K} \lesssim T \lesssim 2.16 \, \mathrm{K}…

Avalanche Dynamics in Stick-Slip Cutting of Molybdenum Disulfide
Pawel Koczanowski, Paolo Nicolini, Hesam Khaksar, Enrico Gnecco
https://arxiv.org/abs/2508.02394 https://…

Avalanche Dynamics in Stick-Slip Cutting of Molybdenum Disulfide
We have investigated nanoscale wear on multilayered MoS2, the flagship transition metal dichalcogenide, by elastically driving sharp diamond tips under normal loads sufficient to induce in-plane fracture. The accompanying friction and the resulting wear structures were first characterized by atomic force microscopy (AFM), revealing a stick-slip regime that drives progressive exfoliation of MoS2 chips. At high normal forces, the slip phase displays hallmark signatures of avalanche dynamics, obse…

Replaced article(s) found for physics.atom-ph. https://arxiv.org/list/physics.atom-ph/new
[1/1]:
- Trapped-ion laser cooling in structured light fields
Zhenzhong Xing, Karan K. Mehta
https://arxiv.org/abs/2411.08844 https://mastoxiv.page/@arXiv_physicsatomph_bot/113480313003086521
- Lorentz and CPT violation and the (anti-)hydrogen molecular ion
Graham M. Shore
https://arxiv.org/abs/2412.09730 https://mastoxiv.page/@arXiv_physicsatomph_bot/113661506443273739
- Bremsstrahlung induced atomic processes
Singh, Kumar, Chatterjee, Swami, Kaur, Jha, Oswal, Singh, Nandi
https://arxiv.org/abs/2501.02967 https://mastoxiv.page/@arXiv_physicsatomph_bot/113786077273931578
- Clarifying Self Seed in 391-nm N$_2^{ }$ Air Lasing by Vectorially Structured Light Fields
Jingsong Gao, Yang Wang, Jiahao Dong, Yi Liu, Chengyin Wu, Hongbing Jiang, Yunquan Liu, Meng Han
https://arxiv.org/abs/2502.01414 https://mastoxiv.page/@arXiv_physicsatomph_bot/113944386182439139
- Linear dichroism signals due to the alignment in the ground state of hydrogen-like atoms and thei...
M. V. Petrenko, A. S. Pazgalev, A. K. Vershovskii
https://arxiv.org/abs/2504.20716 https://mastoxiv.page/@arXiv_physicsatomph_bot/114425750205554960
- Sub-Doppler cooling of bosonic strontium in a two-color MOT
Negyedi, Deutschle, Jessen, Fort\'agh, S\'ark\'any
https://arxiv.org/abs/2507.02693 https://mastoxiv.page/@arXiv_physicsatomph_bot/114794127138414131
- Molecular Quantum Control Algorithm Design by Reinforcement Learning
Anastasia Pipi, Xuecheng Tao, Arianna Wu, Prineha Narang, David R. Leibrandt
https://arxiv.org/abs/2410.11839 https://mastoxiv.page/@arXiv_quantph_bot/113316450427865660
- Single-atom resolved collective spectroscopy of a one-dimensional atomic array
Britton Hofer, Damien Bloch, Giulio Biagioni, Nathan Bonvalet, Antoine Browaeys, Igor Ferrier-Barbut
https://arxiv.org/abs/2412.02541 https://mastoxiv.page/@arXiv_quantph_bot/113593627161222722
- Mutual friction and vortex Hall angle in a strongly interacting Fermi superfluid
Nicola Grani, et al.
https://arxiv.org/abs/2503.21628 https://mastoxiv.page/@arXiv_condmatquantgas_bot/114238880586578320
- Lorentz and CPT violation and the (anti-)hydrogen molecular ion II -- hyperfine-Zeeman spectrum
Graham M Shore
https://arxiv.org/abs/2504.19015 https://mastoxiv.page/@arXiv_hepph_bot/114420102398265292
- Cooling of an optically levitated nanoparticle via measurement-free coherent feedback
Bruno Melo, Daniel Veldhuizen, Gregoire F. M. Tomassi, Nadine Meyer, Romain Quidant
https://arxiv.org/abs/2506.21341 https://mastoxiv.page/@arXiv_quantph_bot/114754750333187473
toXiv_bot_toot

Non Markovian electron Brownian motion with radiation reaction force
Juan Francisco Garc\'ia-Camacho, Oliver Contreras-Vergara, Norma S\'anchez-Salas, Gonzalo Ares de Parga, Jos\'e In\'es Jim\'enez-Aquino
https://arxiv.org/abs/2505.22952

Non Markovian electron Brownian motion with radiation reaction force
In this work, we study non-Markovian electronic plasma diffusion from a classical point of view, taking into account the effects of the radiation reaction force. The electron Brownian motion is described by a Generalized Langevin Equation (GLE) characterized by an Ornstein-Uhlenbeck-type friction memory kernel. To take into account the effects of the radiation reaction force, an effective memory time which accounts for the thermal interaction of the Brownian particle with its surroundings is pr…

Static friction of liquid marbles
Yui Takai, Kei Mukoyama, Pritam Kumar Roy, Guillaume Lagubeau, David Qu\'er\'e, Samuel Poincloux, Timoth\'ee Mouterde
https://arxiv.org/abs/2506.20116

Static friction of liquid marbles
Liquid marbles, droplets coated with a granular layer, are highly mobile as particles prevent capillary adhesion with the substrate. Yet, they exhibit static friction due to their granular shell, which resists rolling until it yields. This friction depends on the shell geometry and increases exponentially with grain density, indicating a logistic dependence of interparticle compressive forces on surface coverage, confirmed by yielding measurements in granular rafts. These results reveal the she…

AgentFacts: Universal KYA Standard for Verified AI Agent Metadata & Deployment
Jared James Grogan
https://arxiv.org/abs/2506.13794 https://

AgentFacts: Universal KYA Standard for Verified AI Agent Metadata & Deployment
Enterprise AI deployment faces critical "Know Your Agent" (KYA) challenges where organizations must verify third-party agent capabilities and establish trust without standardized metadata or verification infrastructure. Current approaches rely on self-declared capabilities and custom integration processes that create trust gaps and coordination friction limiting confident enterprise adoption. This paper presents AgentFacts, a universal metadata standard that enables systematic agent verificatio…

This https://arxiv.org/abs/2505.17418 has been replaced.
initial toot: https://mastoxiv.page/@arXiv_csHC_…

What Needs Attention? Prioritizing Drivers of Developers' Trust and Adoption of Generative AI
Generative AI (genAI) tools are advertised as productivity aids. Yet, issues related to miscalibrated trust and usage friction continue to hinder their adoption. Additionally, AI can be exclusionary, failing to support diverse users adequately, further exacerbating these concerns. One such aspect of diversity is cognitive diversity -- variations in users' cognitive styles -- that leads to divergence in interaction styles. When an individual's cognitive styles are unsupported, it creates additio…

The Stated Protocol: A Decentralized Framework for Digital Diplomacy
Christopher J. P. Rieckmann
https://arxiv.org/abs/2507.13517 https://

The Stated Protocol: A Decentralized Framework for Digital Diplomacy
International coordination faces significant friction due to reliance on periodic summits, bilateral consultations, and fragmented communication channels that impede rapid collective responses to emerging global challenges while limiting transparency to constituents. We present the Stated Protocol, a decentralized framework that enables organizations to coordinate through standardized text statements published on their website domains. While applicable to all organizations, this work focuses pr…

Hydrodynamic Origin of Friction Between Suspended Rough Particles
Jake Minten, Bhargav Rallabandi
https://arxiv.org/abs/2506.21799 https://

Hydrodynamic Origin of Friction Between Suspended Rough Particles
Tangential interactions between particles play a central role in suspension rheology. We show theoretically that these interactions, often attributed to contact friction, are a direct consequence of fluid flows between rough particles in relative motion. We find that small surface asperities generically lead to localized hydrodynamic sliding forces and torques that can exceed their smooth counterparts by orders of magnitude. A fully analytic thin-film theory shows that these forces grow inverse…

Adjusting Tissue Puncture Omnidirectionally In Situ with Pneumatic Rotatable Biopsy Mechanism and Hierarchical Airflow Management in Tortuous Luminal Pathways
Botao Lin, Tinghua Zhang, Sishen Yuan, Tiantian Wang, Jiaole Wang, Wu Yuan, Hongliang Ren
https://arxiv.org/abs/2506.03017

Adjusting Tissue Puncture Omnidirectionally In Situ with Pneumatic Rotatable Biopsy Mechanism and Hierarchical Airflow Management in Tortuous Luminal Pathways
In situ tissue biopsy with an endoluminal catheter is an efficient approach for disease diagnosis, featuring low invasiveness and few complications. However, the endoluminal catheter struggles to adjust the biopsy direction by distal endoscope bending or proximal twisting for tissue sampling within the tortuous luminal organs, due to friction-induced hysteresis and narrow spaces. Here, we propose a pneumatically-driven robotic catheter enabling the adjustment of the sampling direction without t…

Triboelectric charge transfer theory driven by interfacial thermoelectric effect
Ji-Ho Mun, Eui-Cheol Shin, Jaeuk Seo, Yong-Hyun Kim
https://arxiv.org/abs/2507.02528

Triboelectric charge transfer theory driven by interfacial thermoelectric effect
Despite extensive study and the practical significance of friction-driven static electricity, a quantitative triboelectric charge transfer theory has yet to be established. Here, we elucidate the detailed dynamics of triboelectric charge transfer driven by interfacial thermoelectric bias maintaining a steady state at the interface. We demonstrate that triboelectric charge exists in a delta-like distribution at a steady state. We suggest that the transferred triboelectric charge is dictated by h…

Hierarchical friction memory leads to subdiffusive configurational dynamics of fast-folding proteins
Anton Klimek, Benjamin A. Dalton, Lucas Tepper, Roland R. Netz
https://arxiv.org/abs/2506.18823

Hierarchical friction memory leads to subdiffusive configurational dynamics of fast-folding proteins
Proteins often exhibit subdiffusive configurational dynamics. The origins of this subdiffusion are still unresolved. We investigate the impact of non-Markovian friction and the free energy landscape on the dynamics of fast-folding proteins in terms of the mean squared displacement (MSD) and the mean first-passage-time (MFPT) of the folding reaction coordinate. We find the friction memory kernel from published molecular dynamics (MD) simulations to be well-described by a hierarchical multi-expon…

Replaced article(s) found for physics.plasm-ph. https://arxiv.org/list/physics.plasm-ph/new
[1/1]:
- Coherently enhanced radiation friction in laser-plasma collisions
E. G. Gelfer, A. M. Fedotov, M. P. Malakhov, O. Klimo, S. Weber

Learning to Drift with Individual Wheel Drive: Maneuvering Autonomous Vehicle at the Handling Limits
Yihan Zhou, Yiwen Lu, Bo Yang, Jiayun Li, Yilin Mo
https://arxiv.org/abs/2507.23339

Learning to Drift with Individual Wheel Drive: Maneuvering Autonomous Vehicle at the Handling Limits
Drifting, characterized by controlled vehicle motion at high sideslip angles, is crucial for safely handling emergency scenarios at the friction limits. While recent reinforcement learning approaches show promise for drifting control, they struggle with the significant simulation-to-reality gap, as policies that perform well in simulation often fail when transferred to physical systems. In this paper, we present a reinforcement learning framework with GPU-accelerated parallel simulation and sys…

Detectability of dark matter density distribution via gravitational waves from binary black holes in the Galactic center
Zhijin Li, Xiao Guo, Zhoujian Cao, Yun-Long Zhang
https://arxiv.org/abs/2506.19327

Detectability of dark matter density distribution via gravitational waves from binary black holes in the Galactic center
The fundamental nature of dark matter (DM) remains unknown, with significant uncertainties in its density profile. DM environments surrounding massive binary black holes (BBHs) modify their orbital dynamics, thereby altering gravitational wave (GW) emissions. For BBH systems at the Galactic Center, dynamical friction induced by DM spikes could produce detectable deviations in GW spectra, potentially observable by future space-based detectors. To address the uncertainties in the Galactic Center'…

Observational constraints on inflationary models with non-minimally derivative coupling by ACT
Qing Gao, Yanjiang Qian, Yungui Gong, Zhu Yi
https://arxiv.org/abs/2506.18456

Observational constraints on inflationary models with non-minimally derivative coupling by ACT
The most recent data release from the Atacama Cosmology Telescope (ACT) reveals a larger value of the scalar spectral tilt $n_s$, ruling out a broad class of inflationary attractors. In this paper, we consider inflationary models including the power law potential, the hilltop model, the polynomial $α$-attractor and exponential $α-$attractor, with non-minimally derivative coupling in the high friction limit, and show how the models can fit ACT data. We also derive constraints on the model para…

ForcePinch: Force-Responsive Spatial Interaction for Tracking Speed Control in XR
Chenyang Zhang, Tiffany S Ma, John Andrews, Eric J Gonzalez, Mar Gonzalez-Franco, Yalong Yang
https://arxiv.org/abs/2507.18510

ForcePinch: Force-Responsive Spatial Interaction for Tracking Speed Control in XR
Spatial interaction in 3D environments requires balancing efficiency and precision, which requires dynamic tracking speed adjustments. However, existing techniques often couple tracking speed adjustments directly with hand movements, reducing interaction flexibility. Inspired by the natural friction control inherent in the physical world, we introduce ForcePinch, a novel force-responsive spatial interaction method that enables users to intuitively modulate pointer tracking speed and smoothly tr…

An LLM's Apology: Outsourcing Awkwardness in the Age of AI
Twm Stone, Anna Soligo
https://arxiv.org/abs/2506.13685 https://arxiv.…

An LLM's Apology: Outsourcing Awkwardness in the Age of AI
A key part of modern social dynamics is flaking at short notice. However, anxiety in coming up with believable and socially acceptable reasons to do so can instead lead to 'ghosting', awkwardness, or implausible excuses, risking emotional harm and resentment in the other party. The ability to delegate this task to a Large Language Model (LLM) could substantially reduce friction and enhance the flexibility of user's social life while greatly minimising the aforementioned creative burden and mora…

Dancing in the dark: probing Dark Matter through the dynamics of eccentric binary pulsars
Giorgio Nicolini, Andrea Maselli, Miguel Zilh\~ao
https://arxiv.org/abs/2507.16904 http…

Dancing in the dark: probing Dark Matter through the dynamics of eccentric binary pulsars
We investigate the dynamics of eccentric binary pulsars embedded in dark matter environments. While previous studies have primarily focused on circular orbits in collisionless dark matter halos, we extend this framework to eccentric systems and explore their interaction with ultralight scalar fields. Adopting a perturbative approach, we compute the modifications to the orbital period induced by dark matter-driven dynamical friction. Our results show that orbital eccentricity amplifies the impri…

High-Speed Event Vision-Based Tactile Roller Sensor for Large Surface Measurements
Akram Khairi, Hussain Sajwani, Abdallah Mohammad Alkilany, Laith AbuAssi, Mohamad Halwani, Islam Mohamed Zaid, Ahmed Awadalla, Dewald Swart, Abdulla Ayyad, Yahya Zweiri
https://arxiv.org/abs/2507.19914

High-Speed Event Vision-Based Tactile Roller Sensor for Large Surface Measurements
Inspecting large-scale industrial surfaces like aircraft fuselages for quality control requires capturing their precise 3D surface geometry at high resolution. Vision-based tactile sensors (VBTSs) offer high local resolution but require slow 'press-and-lift' measurements stitched for large areas. Approaches with sliding or roller/belt VBTS designs provide measurements continuity. However, they face significant challenges respectively: sliding struggles with friction/wear and both approaches are…

Impact of the history force on the motion of droplets in shaken liquids
Frederik Gareis, Walter Zimmermann
https://arxiv.org/abs/2506.20838 https://…

Impact of the history force on the motion of droplets in shaken liquids
Droplets and solid particles in unsteady flows are affected by the Basset-Boussinesq history force (BBH), in addition to stationary viscous friction, inertia, and gravity. The BBH is often neglected, not because this is generally justified, but because its inclusion in calculations is usually difficult. To assess the significance of BBH for particle dynamics, we revisit unsteady Stokes flows around spherical particles or droplets and derive from first-principles the analytical expressions for t…

Replaced article(s) found for astro-ph.GA. https://arxiv.org/list/astro-ph.GA/new
[1/2]:
- Gaseous Dynamical Friction: a Numerical Study of Extended Perturbers
Ben Morton, Sadegh Khochfar, Jose O\~norbe

Replaced article(s) found for cond-mat.soft. https://arxiv.org/list/cond-mat.soft/new
[1/1]:
- Hydrodynamic Origin of Friction Between Suspended Rough Particles
Jake Minten, Bhargav Rallabandi

Growth rate and energy dissipation in wind-forced breaking waves
Nicol\`o Scapin, Jiarong Wu, J. Thomas Farrar, Bertrand Chapron, St\'ephane Popinet, Luc Deike
https://arxiv.org/abs/2506.17802

Growth rate and energy dissipation in wind-forced breaking waves
We investigate the energy growth and dissipation of wind-forced breaking waves using direct numerical simulations of the coupled air-water Navier-Stokes equations. We vary the wind friction velocity over the wave speed $u_\ast/c$ up to 1. A turbulent wind boundary layer drives the growth of a pre-existing narrowband wave field until it breaks and transfers energy into the water column. Under sustained wind forcing, the wave field then resumes growth. We separately analyze energy transfers durin…

Data-Driven MPC with Data Selection for Flexible Cable-Driven Robotic Arms
Huayue Liang, Yanbo Chen, Hongyang Cheng, Yanzhao Yu, Shoujie Li, Junbo Tan, Xueqian Wang, Long Zeng
https://arxiv.org/abs/2507.15677

Data-Driven MPC with Data Selection for Flexible Cable-Driven Robotic Arms
Flexible cable-driven robotic arms (FCRAs) offer dexterous and compliant motion. Still, the inherent properties of cables, such as resilience, hysteresis, and friction, often lead to particular difficulties in modeling and control. This paper proposes a model predictive control (MPC) method that relies exclusively on input-output data, without a physical model, to improve the control accuracy of FCRAs. First, we develop an implicit model based on input-output data and integrate it into an MPC o…

Fokker-Planck equation for the Brownian motion in the post-Newtonian approximation
Gilberto M. Kremer
https://arxiv.org/abs/2507.11082 https://

Fokker-Planck equation for the Brownian motion in the post-Newtonian approximation
A mixture of light-gas particles and Brownian heavy particles is analyzed within the framework of a post-Newtonian Boltzmann equation to determine the Fokker-Planck equation for the Brownian motion. For each species, the equilibrium distribution function refers to the corresponding post-Newtonian Maxwell-Jüttner distribution function. The expressions for the friction viscous coefficient in the first and second post-Newtonian approximations are determined, and we show their dependence on the co…

Magneto-elastic softening in cold-sprayed polycrystalline nickel studied by resonant ultrasound spectroscopy
Michaela Janovsk\'a (Institute of Thermomechanics, Czech Acad Sci, Prague, Czechia), Petr Sedl\'ak (Institute of Thermomechanics, Czech Acad Sci, Prague, Czechia), Martin \v{S}ev\v{c}\'ik (Institute of Thermomechanics, Czech Acad Sci, Prague, Czechia), Jan Cizek (Institute of Plasma Physics, Czech Acad Sci, Prague, Czechia, Faculty of Mechanical Engineering, Czech Te…

Magneto-elastic softening in cold-sprayed polycrystalline nickel studied by resonant ultrasound spectroscopy
Cold-sprayed metallic deposits are additively manufactured materials containing high levels of compressive residual stress. Here we show that the presence and intensity of this stress can be analyzed using laser-ultrasonics, provided that the sprayed material is ferromagnetic and magnetostrictive, as in the case of pure nickel. Contactless resonant ultrasound spectroscopy is used to monitor the evolution of shear modulus and internal friction parameter of two polycrystalline Ni deposits with te…

Temperature overshooting in the Mpemba effect of frictional active matter
Alexander P. Antonov, Hartmut L\"owen
https://arxiv.org/abs/2507.23137 https://

Temperature overshooting in the Mpemba effect of frictional active matter
The traditional Mpemba effect refers to an anomalous cooling phenomenon when an initial hotter system cools down faster than an initial warm system. Such counterintuitive behavior has been confirmed and explored across phase transitions in condensed matter systems and also for colloidal particles exposed to a double-well potential. Here we predict a frictional Mpemba effect for a macroscopic body moving actively on a surface governed by Coulomb (dry) friction. For an initial high temperature, r…

Rolling, sliding and trapping of driven particles in square obstacle lattices
Galor Geva, Arin Escobar, Paula Magrinya, Pablo Llombart, Alfredo Alexander-Katz, Laura R. Arriaga, Juan L. Aragones
https://arxiv.org/abs/2505.21702

Rolling, sliding and trapping of driven particles in square obstacle lattices
Transport phenomena in complex and dynamic microscopic environments are fundamentally shaped by hydrodynamic interactions. In particular, microparticle transport in porous media is governed by the delicate interplay between particle-substrate friction and pressure forces. Here, we systematically investigate the motion of externally driven rotating magnetic microparticles near a substrate patterned with a square lattice of cylindrical obstacles, a model porous medium. Remarkably, we observe a re…

Finite-temperature properties of the Frenkel-Kontorova model: Relation to tribological systems and fluid rheology
Shubham Agarwal, Martin H. M\"user
https://arxiv.org/abs/2507.14948

Finite-temperature properties of the Frenkel-Kontorova model: Relation to tribological systems and fluid rheology
The Frenkel-Kontorova model is a simple yet generic framework for the description of tribological phenomena and processes, including dry solid friction and the motion of adsorbed layers. As revealed in this work, it also reproduces qualitatively various features of complex liquids, such as, power-law sub-diffusion between the ballistic and the diffusive regimes as well as a cross-over from a non-Arrhenius to an Arrhenius dependence of the diffusion coefficient near the temperature, where the sp…