Einstein's special relativity, established in 1905, unified space and time into a four-dimensional continuum. It relies on two core principles: Galileo's relativity and the constancy of light's speed.

In April 1982, Prof. Dan Shechtman of the Technion–Israel Institute of Technology made the discovery that would later earn him the 2011 Nobel Prize in Chemistry: the quasiperiodic crystal.

For most of us, or perhaps all of us, it's impossible to imagine a world consisting of more than three spatial dimensions. Are we correct when we intuit that such a world couldn't exist?

Sadly, this story marks Roger Delgado’s final appearance as the Master. Shortly after making this story, Delgado was in Turkey to make the film Bell of Tibet. On the way to the location he ...