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:
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—Catherine E. Beecher (1800–1878)
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—Thomas Jefferson (1743–1826)