Ultraviolet complete model of largeNthermal QCD

Abstract

Many recent works on large N holographic QCD in the planar limit have not considered UV completions, restricting exclusively towards analyzing the IR physics. Due to this, the UV problems like Landau poles and divergences of Wilson loops including instabilities at high temperatures have not been addressed. In some of our recent papers, we have discussed a possible UV completion, which is conformal in the UV and confining in the far IR, that avoids the Landau poles and the Wilson loop divergences. In this paper we give a general field theoretic considerations of this including the complete RG flow. We extend our UV complete model to study scenarios both above and below the deconfinement temperature and argue how phase transition in our model should be understood. Interestingly, because of the UV completion, subtle issues like instability due to negative specific heat do not appear.

Non-extremal geometries and holographic phase transitions

“…However by considering N f number of D7 andD7 branes, the chiral U L (N f ) × U R (N f ) symmetry can be realized [68,58] but then the warp factor (2.25) will also be modified. In addition, the warp factor (2.25) only makes sense in the large ρ region which means r min is large.…”

“…Thus the dual geometry with warp factor (2.25) cannot be relevant for a QCD like theory and must be modified for r ∼ Λ → ∞. In [54,58] a proposal was made to modify the UV dynamics of the cascading gauge theory by introducing anti five branes separated from M D5 and N D3 branes along with embedding D7 −D7 branes to account for fundamental matter and chiral symmetry breaking. The additional branes modify G 3 andF 5 while the form of the τ can be obtained from F-theory [66,67].…”

“…Working with the ten dimensional geometry, we avoid the difficulty of KK reduction while extracting the exact RG flow of the gauge theory. The thermal gauge theory studied in [52]- [58] has a rich phase structure and as temperature is altered, we expect phase transitions. Our goal is to study the phase transitions at strong coupling, but to do so, we must first understand how geometries can describe different phases.…”

“…In a series of papers [52]- [58], we proposed the ten dimensional deformed resolved conifold black hole geometry as the dual to UV complete gauge theory which resembles large N thermal QCD. Working with the ten dimensional geometry, we avoid the difficulty of KK reduction while extracting the exact RG flow of the gauge theory.…”

“…Thus the confine-ment/deconfinement phase transition we obtain should mimic the phase transition between confined glue-ball and deconfined gluons of SU (N ) QCD without flavor. In our upcoming work [60], we will incorporate the effect of running dilaton field and other localized sources on the non-extremal geometry which will also give the dual geometric description of UV complete thermal gauge theory.…”