On the critical behavior of D1-brane theories

Abstract

We study renormalization-group flow patterns in theories arising on D1-branes in various supersymmetry-breaking backgrounds. We argue that the theory of N D1-branes transverse to an orbifold space can be fine-tuned to flow to the corresponding orbifold conformal field theory in the infrared, for particular values of the couplings and theta angles which we determine using the discrete symmetries of the model. By calculating various nonplanar contributions to the scalar potential in the worldvolume theory, we show that fine-tuning is in fact required at finite N, as would be generically expected. We further comment on the presence of singular conformal field theories (such as those whose target space includes a "throat" described by an exactly solvable CFT) in the non-supersymmetric context. Throughout the analysis two applications are considered: to gauge theory/gravity duality and to linear sigma model techniques for studying worldsheet string theory.

Don't panic! closed string tachyons in ALE spacetimes

“…There is a closely related context in which world-volume quantum corrections would be important. The world-volume theory of the D1-brane provides a linear sigma model construction analogous to those in [43] of the F-string orbifold CFT [44]. In this one must let the quantum world-volume theory flow to the IR fixed point.…”

“…In the context of quiver theories on D1branes at orbifold points, the classical moduli space is the orbifold space (as we reviewed in §2.2), which is the target space for the F-string world-sheet CFT. Based on this and the discrete symmetries of the theory arising for appropriate choice of theta angles, it was argued in [44] that the D1-brane quiver theory provides a linear sigma model formulation of the orbifold CFT, with the caveat that without supersymmetry one must fine-tune away the quantum potential on the moduli space in order to reach the orbifold CFT in the IR (which then enjoys an accidental supersymmetry).…”

The Experience Machine

“…29 A further possibility is suggested by Matthew Silverstein. 30 According to Silverstein, '[o]ur [well-being] intuitions tend to ref lect our desires and preferences', and we have been conditioned to have a strong 'desire to remain connected to the real world, to track reality'. 31 Why have we been conditioned to have this desire?…”

Infra-red dynamics of D1-branes at the conifold

“…These arise from the values of scalars X m a corresponding to the diagonal U(1)'s. The question of finding backgrounds for matrix string theory where an U(1) R is present in the ultraviolet gauge theory which appears as the world sheet U(1) R was raised recently in [24]. In the ultraviolet of this matrix theory, there is a superpotential.…”

“…The author thanks E. Silverstein and Y. S. Song for pointing out that for this matrix theory too, the question in[24] is unresolved, correcting the erroneous conclusion in the earlier draft.…”