Gemini Observatory/NSF/AURA/J. Lomberg
The Hierarchical Theory
Arguably, the most widely accepted theory of galactic formation says that galaxies formed from “collisions” of smaller structures, which then evolved over the past 8-11 billion years into the galaxies we see today. This is called the “Hierarchical Theory”. The Gemini Deep Deep Survey brings into question key predictions of the Hierarchical Theory.
