| Issue |
EPJ Web Conf.
Volume 340, 2025
Powders & Grains 2025 – 10th International Conference on Micromechanics on Granular Media
|
|
|---|---|---|
| Article Number | 12004 | |
| Number of page(s) | 4 | |
| Section | Emerging Topics: Additive Manufacturing & Meta Materials, Microgravity, Tribo-Charging, Active Particles, and Artificial Intelligence & Machine Learning | |
| DOI | https://doi.org/10.1051/epjconf/202534012004 | |
| Published online | 01 December 2025 | |
https://doi.org/10.1051/epjconf/202534012004
Density-field structures in a few systems undergoing velocity ordering
1 Theoretical Sciences Unit and School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P.O., Bangalore 560064, India
2 Department of Physics and Astrophysics, University of Delhi, Delhi 110007, India
3 Le laboratoire interdisciplinaire de Physique, Université Grenoble Alpes, 140, Rue de la Physique, 38402 St. Martin d’Hères, France
4 Department of Physics “A. Pontremoli”, University of Milan, via Celoria 16, 20133 Milan, Italy
* e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Published online: 1 December 2025
Abstract
We consider two (off-lattice) varieties of out-of-equilibrium systems, viz., granular and active matter systems, that, in addition to displaying velocity ordering, exhibit fascinating pattern formation in the density field, similar to those during vapor-liquid phase transitions. In the granular system, velocity ordering occurs due to reduction in the normal components of velocities, arising from inelastic collisions. In the active matter case, on the other hand, velocity alignment occurs because of the inherent tendency of the active particles to follow each other. Inspite of this difference, the patterns, even during density-field evolutions, in these systems can be remarkably similar. This we have quantified via the calculations of the two-point equal time correlation functions and the structure factors. These results have been compared with the well studied case of kinetics of phase separation within the framework of the Ising model. Despite the order-parameter conservation constraint in all the cases, in the density field, the quantitative structural features in the Ising case is quite different from those for the granular and active matters. Interestingly, the correlation function for the latter varieties, particularly for an active matter model, quite accurately describes the structure in a real assembly of biologically active particles.
© The Authors, published by EDP Sciences, 2025
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.