Domain wall (string theory)

In physics, a domain wall is any of several similar things in string theory, magnetism, or optics. These phenomena can all be generically described as topological solitons that occur whenever a discrete symmetry is spontaneously broken.[1]

String theory

In string theory, a domain wall is a theoretical 2-dimensional singularity. A domain wall is meant to represent an object of codimension one embedded into space (a defect in space localized in one spatial dimension). For example, D8-branes are domain walls in type II string theory. In M-theory, the existence of Horava–Witten domain walls, "ends of the world" that carry an E8 gauge theory, is important for various relations between superstring theory and M-theory.

If domain walls exist, it seems plausible that gravitational waves would be violently emitted if two such walls collided. As the Laser Interferometer Gravitational-Wave Observatory and future observatories of its kind will search for direct evidence of gravitational waves, this phenomenon would be included as well in such searches.

See also

References

  1. S. Weinberg, The Quantum Theory of Fields, Vol. 2. Chap 23, Cambridge University Press (1995).