On the Ubiquity of (Almost) Contact Structures in Hot MQCD at Intermediate Coupling

TL;DR

This paper explores the geometric structures in a top-down M-theory dual of thermal QCD-like theories at intermediate coupling, revealing new contact structures and their implications for holographic phenomena such as entanglement entropy and chaos.

Contribution

It explicitly constructs (Almost) Contact structures and SU(3) structures on a warped G2 manifold, revealing novel geometric properties relevant to holographic QCD.

Findings

Subspaces of C3S and AC3S are not mutually N-path connected in IR.

Explicit geometric structures are derived for the M-theory background.

Results have implications for entanglement entropy, chaos, and transport in holographic QCD.

Abstract

Relevant to top-down ${\cal M}$-theory dual of large-$N$ thermal QCD-like theories at intermediate coupling, induced by the $G_2$ structure supported by the closed $M_7$ - a warped product of the ${\cal M}$-theory circle and a non-K\"{a}hler six-fold which is the warped product of the thermal circle with a non-Einsteinian deformation of $T^{1,1}$ - we obtain explicitly (Almost) Contact (3) (Metric)Structure(s) and a three-tuple of $SU(3)$ structures along the "transverse" six-fold induced by the AC(3)MS on $M_7$. A novel result in this context is that in the Infra-Red, within the parameter space of AC3S arising from G2 structures, the subspaces of C3S and AC3S are not mutually "N-path connected". Relevance of the results to staying out of the non-supersymmetric swampland, entanglement entropy of eternal black holes, chaos, bulk-to-shear viscosity ratio $\frac{\zeta}{\eta}$, paramagnetic plasma EoS and photoproduction in a strong magnetic field, in the context of top-down holographic thermal QCD at intermediate coupling, is highlighted/reiterated.