Hierarchical Reconstruction of the Cosmic Web, The H-Spine method

TL;DR

The paper introduces the H-Spine method, a hierarchical framework for identifying and characterizing the nested structures of the cosmic web, capturing their geometry, interconnectivity, and scale-dependent properties.

Contribution

The H-Spine method provides a novel hierarchical approach to analyze cosmic web structures, improving understanding of their geometry, nesting, and interrelations over previous single-scale methods.

Findings

Identified density and size distributions of cosmic web structures at multiple hierarchical levels.

Demonstrated the method's ability to reveal scale-dependent properties of voids, walls, and filaments.

Showed the interconnectivity and nesting relations among cosmic structures.

Abstract

The cosmic web consists of a nested hierarchy of structures: voids, walls, filaments, and clusters. These structures interconnect and can encompass one another, collectively shaping an intricate network. Here we introduce the Hierarchical Spine (H-Spine) method, a framework designed to hierarchically identify and characterize voids, walls, and filaments. Inspired by the geometrical and dynamical constraints imposed by anisotropic gravitational collapse, the H-Spine method captures the geometry and interconnectivity between cosmic structures as well as their nesting relations, offering a more complete description of the cosmic web compared to single-scale or multi-scale approaches. To illustrate the method's utility, we present the distribution of densities and sizes of voids, walls and filaments identified in a 3-level hierarchical space. This analysis demonstrates how each level within the hierarchy unveils distinctive densities and scales inherent to cosmic web elements.