Here’s what you’ll learn when you read this story: Theoretical physicists believe math shows the possibilities of a fourth dimension, but there’s no actual evidence—yet. Albert Einstein believed space ...

Is time something that flows — or just an illusion? Exploring space-time as either a fixed “block universe” or a dynamic ...

How would our world be viewed by observers moving faster than light in a vacuum? Such a picture would be clearly different from what we encounter every day. We should expect to see not only phenomena ...

A fringe new theory suggests that time is the fundamental structure of the physical universe, and space is merely a byproduct. According to Gunther Kletetschka, a geologist — not a physicist, you’ll ...

In a hypertorus model of the Universe, motion in a straight line will return you to your original location, even in an uncurved (flat) spacetime. The Universe could also be closed and positively ...