# Asymmetric and Long Range Interactions in Shaken Granular Media

## TL;DR

This study uses computational modeling to reveal long-range attractive forces and interaction dynamics between intruders in a vibrated granular medium, highlighting the influence of shaking parameters and packing density.

## Contribution

It introduces a detailed computational analysis of long-range interactions and effective forces between intruders in vibrated granular media, emphasizing the role of shaking parameters.

## Key findings

- Emergence of long-range attractive forces between intruders.
- Interaction forces depend on shaking angle, amplitude, and packing density.
- No density gradients, but additive kinetic energy gradients observed.

## Abstract

We use a computational model to investigate the emergence of interaction forces between pairs of intruders in a horizontally vibrated granular fluid. The time evolution of a pair of particles shows a maximum of the likelihood to find the pair at contact in the direction of shaking. This relative interaction is further studied by fixing the intruders in the simulation box where we identify effective mechanical forces, and torques between particles and quantify an emergent long range attractive force as a function of the shaking relative angle, amplitude, and the packing density of grains. We determine the local density and kinetic energy profiles of granular particles along the axis of the dimer to find no gradients in the density fields and additive gradients in the kinetic energies.