Merging and fragmentation in the Burgers dynamics
Francis Bernardeau1, Patrick Valageas
1Institut de Physique Théorique, CEA/DSM/IPhT, Unité de recherche associée au CNRS, CEA/Saclay, Gif-sur-Yvette, France.
Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|September 28, 2010
Summary
We investigate the adhesion model in cosmology, revealing that halo fragmentation occurs in 2D and higher dimensions. Pointlike halos merge via three-body collisions, leading to continuous halo formation through fragmentation and merging.
Area of Science:
- Cosmology
- Astrophysics
- Fluid Dynamics
Background:
- The adhesion model describes large-scale structure formation in the universe.
- Previous studies focused on specific aspects of this model.
Purpose of the Study:
- To explore noiseless Burgers dynamics in the inviscid limit using a geometrical model.
- To analyze matter distribution and space partitions within this framework.
Main Methods:
- Utilizing a geometrical model based on Legendre transforms and convex hulls.
- Analyzing matter evolution within the shock manifold.
- Investigating Lagrangian space triangulation and Eulerian space tessellation.
Main Results:
- Halo mass distribution arises from Lagrangian space triangulation.
- Eulerian space tessellation defines empty regions with shock nodes.
- Halo fragmentation occurs in dimensions >= 2.
- Pointlike halos merge via three-body collisions; two-body collisions create new shock nodes.
Conclusions:
- The geometrical model provides insights into halo fragmentation and merging dynamics.
- This leads to a continuous formation of massive halos.
- The findings generalize to higher spatial dimensions.
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