Big bang and expansion of the universe (K-A)

• Big bang introduction-video (K-A)
• Radius of observable universe-video (K-A)
• Radius of observable universe (correction)-video (K-A)
• Red shift-video (K-A)
• Cosmic background radiation 2-video (K-A)
• Hubble's law-video (K-A)
• A universe smaller than the observable-video (K-A)
• How can the universe be infinite if it started expanding 13.8 billion years ago?-link (K-A)