Is The Universe Finite?

Every time you walk out the door, light from the Big Bang strikes your face, enters your eyes. This is the cosmic microwave background radiation - the left-over heat-glow from the very early universe. We can’t see this microwave light with our eyes, but we can catch it with even a simple radio antenna. As soon as we became aware of its existence we’ve been feverishly building better and better devices to collect it. Why? Because it encodes so many secrets. And within this light, a group of scientists have just found evidence of the limits of space. A clue that our universe may be actually be finite in size. Today on Space Time Journal Club we’ll delve into the Nature Astronomy paper that just reported this: Planck evidence for a closed Universe and a possible crisis for cosmology by Eleonora Di Valentino, Alessandro Melchiorri, and Joe Silk.