The workshop description

1. Introduction

We are organizing a conference on the study of the Cosmic Web, and in particular its morphological and topological aspects. The meeting is a multidisciplinary workshop, bringing together experts from cosmology and astrophysics with those specialized in computational geometry and topology. These fields provide innovative new avenues for the mining of significant new information contained in the patterns and morphology of the anisotropic web-like structures that we see in the galaxy distribution.

2. The Cosmic Web

The Cosmic Web is one of the most intriguing and intricate spatial patterns in Nature. The web-like spatial arrangement of galaxies and mass into elongated filaments, sheetlike walls and dense compact clusters, the existence of large near-empty void regions and the hierarchical nature of this mass distribution are the three major characteristics of the cosmic matter distribution on scales of millions of light years. They are the product of the gravitational growth of tiny primordial density perturbations, which were (almost perfectly) Gaussian by nature and generated during the inflationary era shortly after the Big Bang. The analysis of the cosmic web is far from trivial. Despite the multitude of elaborate qualitative descriptions it has remained a major challenge to characterize the structure, geometry and topology of the Cosmic Web. Quantities as basic and general as the mass and volume content of clusters, filaments, walls and voids are still not well established or defined. Since there is not yet a common framework to objectively define filaments and walls, the comparison of results of different studies concerning properties of the filamentary network such as their internal structure and dynamics, evolution in time, and connectivity properties is usually rendered cumbersome and/or difficult.
The overwhelming complexity of the individual structures as well as their connectivity, the lack of structural symmetries, its intrinsic multiscale nature and the wide range of densities that one finds in the cosmic matter distribution has prevented the use of a simple and straightforward tool box. Over the years, a variety of heuristic measures were proposed to analyze specific aspects of the spatial patterns in the large scale Universe. Only in recent years these have lead to a more solid and well-defined machinery for the description and quantitative analysis of the intricate and complex spatial patterns of the Cosmic Web. Nearly without exception, these methods borrow extensively from other branches of science such as image processing, mathematical morphology, computational geometry and medical imaging.

3. The Workshop

Recent work has shown the potential of obtaining constraints from the topology of the cosmic web on the nature of dark matter and dark energy in the Universe, and the possible primordial non-Gaussian nature of the primordial fluctuations. In this workshop we intend to

  1. review the current status of various programs and methods to analyze the morphology and topology of the cosmic web,
  2. learn about state-of-the-art results and insights from prominent experts in computational geometry and topology,
  3. discuss about and exchange insights on specific requirements and characteristics of the cosmic mass distribution for the application of instruments from computational topology.
  4. In addition, the workshop will also
  5. focus on the dynamics and structure of the cosmic web on the basis of large state-of-the-art supercomputer simulations, analytical models and from the analysis of current cosmological databases.