منابع مشابه
Semiglobal Alice strings.
We show that in certain theories with topologically trivial quotient space of spontaneously broken gauge symmetry there can exist topologically stable strings that carry nonabelian gauge flux. These objects result from the “accidental” global degeneracy of the vacuum which makes it topologically nontrivial. In particular, some models contain the semiglobal analog of the Alice strings. ∗Permanen...
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Alice strings are cosmic strings that turn matter into antima,tter. Although they arise naturally in many GUT’s, it has long been believed that because of the monopole problem they can have no cosmological effects. We show this conclusion to be false; by using the Langacker-Pi mechanism, monopoles can in fact be annihila.ted while Alice strings are left intact. This opens up the possibility tha...
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We study a system of Nc D3-branes intersecting D7-branes and O7-planes in 1 + 1-dimensions. We use anomaly cancellation and string dualities to argue that there must be chiral fermion zero-modes on the D3-branes which are localized near the O7planes. Away from the orientifold limit we verify this by using index theory as well as explicit construction of the zero-modes. This system is related to...
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This talk reports on recent progress toward the semiglobal study of asymptotically flat spacetimes within numerical relativity. The development of a 3D solver for asymptotically Minkowski-like hyperboloidal initial data has rendered possible the application of Friedrich’s conformal field equations to astrophysically interesting spacetimes. As a first application, the whole future of a hyperbolo...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 1995
ISSN: 0556-2821
DOI: 10.1103/physrevd.51.7148