N=2 superconformal boundary states for free bosons and fermions

We embed the supersymmetry breaking mechanism in N = 1 SQCD of hepth/0602239 in a smooth superstring theory using D-branes in the background IR 4 × SL(2) k=1 /U (1) which smoothly captures the throat region of an intersecting N S5-brane configuration. A controllable deformation of the supersymmetric branes gives rise to the mass deformation of the magnetic SQCD theory on the branes. The consequent instability on the open string worldsheet can be followed onto a stable non-supersymmetric configuration of D-branes which realize the metastable vacuum configuration in the field theory.The new brane configuration is shown to backreact onto the background such as to produce different boundary conditions for the string fields in the radial direction compared to the supersymmetric configuration. In the string theory, this is interpreted to mean that the supersymmetry breaking is explicit rather than spontaneous.

Section: Unstable Brane Configurations Which Spontaneously Break Supementioning

confidence: 85%

On supersymmetry breaking in string theory from gauge theory in a throat

Murthy¹

2007

“…Only partial results in this direction are available up to now [45,46,47,15,48]. A detailed knowledge about the CFT construction of generalised permutation branes in product groups and cosets would certainly be a major step forward.…”

Section: Discussionmentioning

confidence: 99%

Generalised permutation branes

Fredenhagen

Quella

2005

We propose a new class of non-factorising D-branes in the product group G × G where the fluxes and metrics on the two factors do not necessarily coincide. They generalise the maximally symmetric permutation branes which are known to exist when the fluxes agree, but break the symmetry down to the diagonal current algebra in the generic case. Evidence for the existence of these branes comes from a Lagrangian description for the open string world-sheet and from effective Dirac-Born-Infeld theory. We state the geometry, gauge fields and, in the case of SU (2) × SU (2), tensions and partial results on the open string spectrum. In the latter case the generalised permutation branes provide a natural and complete explanation for the charges predicted by K-theory including their torsion.

“…However, the complete moduli space of all conformal Dbranes for such conformal field theories is not known; the description of all of these branes is likely to be a complicated problem since the number of conformal Ishibashi states grows out of control for central charges bigger than one. 13 The known constructions of one theory will then typically correspond to branes that are unfamiliar from the other point of view; it is therefore not obvious how one should compare the brane spectra of these theories.…”

Section: Conclusion and Open Problemsmentioning

confidence: 99%

D-branes at multicritical points

Gaberdiel

Israël

Rabinovici

2008

The moduli space of c = 1 conformal field theories in two dimensions has a multicritical point, where a circle theory is equivalent to an orbifold theory. We analyse all the conformal branes in both descriptions of this theory, and find convincing evidence that the full brane spectrum coincides. This shows that the equivalence of the two descriptions at this multicritical point extends to the boundary sector. We also perform the analogous analysis for one of the multicritical points of the N = 1 superconformal field theories at c = 3 2 . Again the brane spectra are identical for both descriptions, however the identification is more subtle. *