Fly-Through Of Early Universe and Ionization Era

The movie shows the universe as seen from an observer in the top-left corner, with the last-scattering surface - from which the cosmic microwave background (CMB) originates at redshift of z=1100 - seen as the inner edge of the outermost white ring. The outer edge of the ring corresponds to the big bang at time=0, indicating that the observable universe is finite in size - about 14 Gpc, or 40 billion light-years in radius. Since the universe has a flat geometry, all the angular sizes shown here are correct, because the map corresponds to the "comoving" distance from the observer, indicating the location of the material at the present time. This is why the entire observable universe is currently 40 billion light-years in radius, even though the light has only been travelling for about 13.7 billion years since the big bang.

The movie then zooms in to a point at a redshift of about z=30, hundreds of millions of years after the big bang. As we fly toward the observer, the universe gets more and more ionized and is heated. Hot is shown as white, about 20,000 degrees Kelvin, while black is cold, neutral gas. Inhomogenous reionization leaves behind a complex post-reionization temperature morphology, since the first regions to ionize in fact are the coolest.

credit: Marcelo A. Alvarez

source: http://www.cita.utoronto.ca/~malvarez/movies.shtml

Category:

Science & Technology

[djxatlanta]

@jiberish001 - it's a analogy... The earth (3D) appears flat (2D) while we're standing on it, and its curvature only becomes apparent with distance. Likewise, the universe (4D) appears flat (3D) from any given viewpoint and its inherent curvature only becomes apparent from extraordinarily great distances or with the passage of time.

[jiberish001]

"Since the universe has a flat geometry"... what!? Who wrote that? It makes no sense. Perhaps you could define what they mean by "flat"?