It is hard to take space-time seriously. What is the consequence for the four-dimensional shape  of our universe? For better understanding, this article uses 2-d sections to visualize  Einstein’s first model. This static model used a cosmological constant which Einstein later withdrew. The authors present a new 3-sphere...

The age of our universe depends on the estimate of the Hubble constant. Recent measurements (WHAP, Planck, ed) would mean an age of more than 14.5 billion years. This article takes a different approach, based on Noether’s theorem on energy conservation and the comoving coordinates of Robertson and Walker. The age now...