The inner structure of Zeldovich pancakes
2003 (English)In: Physica D: Non-linear phenomena, ISSN 0167-2789, Vol. 186, no 04-mar, 171-184 p.Article in journal (Refereed) Published
The evolution of a planar perturbation in a Einstein-de Sitter Universe is studied using a previously introduced Lagrangian scheme. An approximate discrete dynamical system is derived, which describes the mass agglomeration process. Quantitative predictions for the late-time mean density profile are obtained therefrom, and validated by numerical simulations. A simple but important result is that the characteristic scale of a mass agglomeration is an increasing function of cosmological time t. For one kind of initial conditions we further find a scaling regime for the density profile of a collapsing object. These results are compared with analogous investigations for the adhesion model (Burgers equation with positive viscosity). We further study the mutual motion of two mass agglomerations, and show that they oscillate around each other for long times, like two heavy particles. Individual particles in the two agglomerations do not mix effectively on the time scale of the inter-agglomeration motion.
Place, publisher, year, edition, pages
2003. Vol. 186, no 04-mar, 171-184 p.
self-gravitating dynamics, mass density, adhesion model, burgers equation, large-scale structure, universe, equation
IdentifiersURN: urn:nbn:se:kth:diva-23067DOI: 10.1016/j.physd.2003.07.004ISI: 000187730600004OAI: oai:DiVA.org:kth-23067DiVA: diva2:341765
QC 201005252010-08-102010-08-10Bibliographically approved