Is there such thing as hyperspace? Is it or will it one day be possible to travel through it?
We're not sure if there is a "hyperspace" or not!
A hyperspace is a space with more than the "usual" 4 dimensions, that is 3 spatial dimensions and 1 time dimension (the 3 spatial and 1 time dimensions are collectively referred to as "spacetime"). Whether this actually exists or not is still a matter of debate. Conventional physical theories like general relativity, quantum mechanics and electrodynamics require only 4 dimensions. However, some of these theories are incompatible with each other in certain physical regimes: for instance, general relativity doesn't work very well at describing systems where quantum mechanics is important, and vice-versa. Many physicists are therefore trying to develop "unifying" theories, or theories that interpret the Universe at a more fundamental level than the ones we currently have do. Theories like quantum mechanics and general relatvity could then be "derived" from the same unified theory, resolving the compatibility issues. Many popular unifying theories operate in many-dimensional hyperspaces; a good example is string theory, which invokes 11 dimensions! Although these theories are partially successful at reproducing conventional physics, they remain very incomplete and largely unproven.
So, whether one actually requires a hyperspace to understand the Universe remains unknown, and will likely remain so for a few decades. If hyperspace does indeed exist, your guess at how travel through it would be is as good as mine!
This page was last updated June 27, 2015.