I last showed that the AdS/CFT correspondence states that, for large N, classical supergravity on this background is dual to strongly coupled 4-d N = 4 SU(N) superYang-Mills theory and the conformality of the 4-d theory is reflected by translational invariance along the r direction of the 5-d AdS space and provides a stringy realization of the Randall-Sundrum-II model
This is deep, and in this post, I will delve into Klebanov-Strassler warped throat conifold analysis. Recal that the low-energy limit of type IIB superstring theory is type IIB supergravity, whose action is
by which is meant ‘fermion-terms’, with the 10-d reduced Planck mass, and the 10-d Einstein frame metric with Ricci scalar , and is the axio-dilaton, formed from the Ramond-Ramond axion , with the dilaton defined by
and that placing N coincident D3-branes in 10-d flat spacetime will deform the warped-throat internal-space metric, thus yielding
with
visually…
and this space is asymptotically flat as , given that . For small , the second term dominates, and the metric becomes that of
with the branes sourcing N units of flux through the internal . In this post, I will try and show via
Klebanov-Strassler warped conifold analysis, that the AdS/CFT dual of supergravity on the warped conifold background is a 4-D N = 1 superconformal gauge theory
First, note that a Klebanov-Strassler geometry naturally arises by considering string theory compactification on where is the Einstein manifold in five dimensions, with the interaction-Lagrangian of the massless Klebanov-Strassler field and the brane fields fermions is
and after integrating over the extra dimensional part, the effective 4-D Lagrangian reduces to
with the fundamental Planck scale and the 4-D Planck scale related as
Let us consider a IIB compactification on a Calabi-Yau 3-fold M which has a conical singularity. Placing N D3-branes at the singular point yields a deformation of the metric as in above, and is
with
And this is deep because:
spacetime at small converges to the throat, whereas at large it is given by
and hence, in the throat, supergravity is dual to a conformal field theory in 4-D. The Klebanov-Strassler warped deformed conifold arises by considering
The conifold is the cone over : a non-compact singular Ricci-flat manifold
The metric near N D3-branes at a conifold singularity is
and with
with solution N units of flux through the internal , visually as
and is topologically ,
and at the conifold singularity both the 3-cycle and the 2-cycle shrink to zero size
The deformed conifold is a non-singular, non-compact manifold that admits a Calabi-Yau metric and when placing M units of flux on the 3-cycle, the flux backreaction on the geometry gives the warped deformed conifold. One can interpret this flux as sourced by D-branes and crucially, as noted visually, in the warped conifold throat context, D3-branes live at the singularity
The throat metric, excluding the tip, is the Klebanov-Tseytlin one
with
with is the singularity deformation parameter size, and the Klebanov-Tseytlin metric becomes singular for and no longer valid in the domain , and the complete throat is perfectly smooth also at its tip, thus we have the following ‘picture’
And as one goes along the throat, there are units of flux through at the radial coordinate r
With the general ansatz
the logarithmic dependence
of on can be be gotten as such: for a finite segment of the throat, between and , we have
Since is imaginary self-dual, one has
and because has zero components in the direction, one can derive
with the metric being
and inserting into
and differentiating, one gets
and with the quantization condition
implying the scaling for the non-vanishing components of , we get our desired result