Physical Society Colloquium

Cosmology and the Shape of Large-Scale Structure

Neta Bahcall

Princeton University

Superclusters — the largest structures in the Universe — range in size from a few Mpc to the “Great Walls” of hundreds of Mpc. What is the shape of these large-scale structures — are they filamentary in nature or are they flattened two-dimensional “pancakes”? How do they form and evolve? Superclusters are typically dominated by clusters of galaxies, systems that have served as powerful tools in cosmology. What is the shape of clusters — are they spherically symmetric or are they elliptical? Are they aligned with each other on large scales? I present results that answer these fundamental questions, revealing the predicted shape and evolution of large-scale structure in the Universe in the current popular cosmology. The results provide a new independent tool in constraining cosmology, as well as provide clues to the formation and evolution of large-scale structure.