Tie a trefoil knot in a piece of string, seal the ends together, and try to wiggle it free without cutting. In three-dimensional space, the knot holds firm. Add a fourth spatial dimension, however, ...

Reintroduction : View from the twenty-first century -- Augmenting a 1983 history of the fourth dimension in culture and art (1900-1950) : X-rays and ether physics as the context for the "fourth ...

A group of researchers from Virginia Tech are attempting to find a fourth spatial dimension of the universe. If they succeed, their discovery would literally change how people view the world. "Since ...

(via New Scientist) For a long time now, the idea of a fourth dimension has hovered at the edge of science and science fiction, a concept so elusive and mysterious that many of us find it almost ...