Related papers: Dynamical friction for accelerated motion in a gas…
The process of momentum and energy transfer between a massive body and a background medium it is moving through is known as dynamical friction (DF). It is key to our understanding of many astrophysical systems. We present a series of…
In a gaseous medium, dynamical friction (DF) reaches a maximum when the orbital speed of a (point-like) perturber moving on a circular orbit is close to the sound speed. Therefore, in a quasi-steady state, eccentric orbits of perturbers…
We present a study of equal-mass hyperbolic encounters, embedded in a uniform gaseous medium. Using linear perturbation theory, we calculate the density wakes excited by these perturbers and compute the resulting forces exerted on them by…
We investigate by means of numerical simulations with nested Cartesian meshes the force exerted on a massive and luminous perturber moving at constant speed through a homogeneous and opaque gas, taking into account thermal diffusion in the…
We use three-dimensional hydrodynamic simulations to investigate the nonlinear gravitational responses of gas to, and the resulting drag forces on, very massive perturbers moving on circular orbits. This work extends our previous studies…
In models of dark matter composed of feebly interacting ultralight bosons in the state of Bose-Einstein condensate, the dynamical friction force acting on circularly moving globular clusters modelled as Plummer spheres is determined.…
We compute the Gaseous Dynamical Friction (GDF) force experienced by massive perturbers on elliptical Keplerian orbits. In this paper, we investigate the density wake morphology, dynamical friction force, and secular orbital evolution for…
The dynamic frictional force between solid surfaces in relative motion differs from the static force needed to initiate motion, but this distinction is not usually thought to occur for liquid drops moving on a solid. Recent experiments…
It is shown using the method of molecular dynamics that the motion of carbon nanoparticles (rectangular graphene flakes, spherical fullerenes of size $L<10$ nm) on the surface of a thermalized graphene sheet lying on a flat substrate can be…
The analytical generalization of the classical dynamical friction formula (derived under the assumption that all the field particles have the same mass) to the case in which the masses of the field particles are distributed with a mass…
We derive an analytical model for the so-called phenomenon of `resonant dynamical friction', where a disc of stars around a super-massive black hole interacts with a massive perturber, so as to align its inclination with the disc's…
We explore dynamic structural superlubricity for the case of a relatively large contact area, where the friction force is proportional to the area (exceeding $\sim 100\,nm^2$) experimentally, numerically, and theoretically. We use a setup…
Frictional motion is harder to initiate than to sustain, as evident when pushing a heavy object. This disparity between static and kinetic friction drives instabilities and stick-slip dynamics in systems ranging from nanodevices and MEMS to…
The orbital decay of massive black holes in galaxies in the aftermath of mergers is at the heart of whether massive black holes successfully pair and merge, leading to emission of low-frequency gravitational waves. The role of dynamical…
This work addresses friction-induced modal interactions in jointed structures, and their effects on the passive mitigation of vibrations by means of friction damping. Under the condition of (nearly) commensurable natural frequencies, the…
We consider the intermediate mass-ratio inspiral of a stellar-mass compact object with an intermediate-mass black hole that is surrounded by a dark matter density spike. The interaction of the inspiraling black hole with the dark matter…
An introductory exposition of Chandrasekhar's gravitational dynamical friction, appropriate for an undergraduate class in mec hanics, is presented. This friction results when a massive particle moving through a ``sea'' of much lighter star…
We perform large-scale molecular dynamics simulations to study heated granular fluids in three dimensions. Granular particles dissipate their kinetic energy due to solid frictional interaction with other particles. The velocity of each…
Using molecular dynamics we study the dependence of the friction force on the sliding speed when an elastic slab (block) is sliding on a rigid substrate with a ${\rm sin} (q_0 x)$ surface height profile. The friction force is nearly…
The dynamic evolution of galactic bars in standard $\Lambda$CDM models is dominated by angular momentum loss to the dark matter haloes via dynamical friction. Traditional approximations to dynamical friction are formulated using the…