Abstract
Goldstone’s theorem states that there is a massless mode for each broken symmetry generator. It has been known for a long time that the naive generalization of this counting fails to give the correct number of massless modes for spontaneously broken spacetime symmetries. We explain how to get the right count of massless modes in the general case, and discuss examples involving spontaneously broken Poincaré and conformal invariance.
- Received 1 November 2001
DOI:https://doi.org/10.1103/PhysRevLett.88.101602
©2002 American Physical Society