Several speculative physical theories have introduced extra dimensions of space for various reasons:
- Kaluza–Klein theory introduces extra dimensions to explain the fundamental forces other than gravity (originally only electromagnetism).
- Large extra dimension and the Randall–Sundrum model attempt to explain the weakness of gravity. This is also a feature of brane cosmology.
- The extra dimensions in superstring theory are required for mathematical consistency and are often assumed to have the shape of a Calabi–Yau manifold.
- Universal extra dimension
"Extra dimensions" may also refer to:
- Parallel universe (fiction)
Famous quotes containing the words extra and/or dimensions:
“Celebrity is a mask that eats into the face. As soon as one is aware of being “somebody,” to be watched and listened to with extra interest, input ceases, and the performer goes blind and deaf in his overanimation. One can either see or be seen.”
—John Updike (b. 1932)
“I was surprised by Joe’s asking me how far it was to the Moosehorn. He was pretty well acquainted with this stream, but he had noticed that I was curious about distances, and had several maps. He and Indians generally, with whom I have talked, are not able to describe dimensions or distances in our measures with any accuracy. He could tell, perhaps, at what time we should arrive, but not how far it was.”
—Henry David Thoreau (1817–1862)