What / Why ? you ask.
Well, the opening comment explains:
"If the big bang were true, the light from the fireball should cast shadows in the foreground of all galaxy clusters."
It seems there are no shadows. Hmmm.
The article will explain.
And -- not to fear --
the article is short and an easy read so do not be afraid to check it out.
HERE'S THE LINK to Light from the big bang casts no shadows
