Holographic computation of Wilson loops in a background with broken conformal invariance and finite chemical potential

Abstract

In this paper, we follow a 'bottom-up' AdS/QCD approach to holographically probe the dynamics of a moving qq pair inside a strongly coupled plasma at the boundary. We consider a deformed AdS-Reissner Nordström metric in the bulk in order to introduce nonconformality and finite quark density in the dual field theory. By boosting the gravity solution in a specific direction we consider two extreme cases of orientation, θ = 0, π/2, for the Wilson loop which in turn fixes the relative position of the qq pair with respect to the direction of boost in the plasma. By utilizing this set-up, we holographically compute the vacuum expectation value of the time-like Wilson loop in order to obtain real part of the qq potential and the effects of nonconformality (deformation parameter c), chemical potential µ and rapidity β is observed on this potential. We then compute the in-medium energy loss of the moving parton (jet quenching parameter q m ) by setting β → ∞ which in turn makes the Wilson loop light-like. We also use the jet quenching as a order parameter to probe strongly-coupled domain of the dual field theory. Finally, we compute the imaginary part of the qq potential Im(V qq ) by considering the thermal fluctuation (arbitrary long wavelength) of the string world-sheet. *

Running coupling constant at finite chemical potential and magnetic field from holography *

“…The interaction between two quarks are reflected by the running coupling or the heavy quark -antiquark potential (free energy). In our previous study [81,92], we found that chemical potential and magnetic field will change the free energy of . Since the running coupling is extracted from the free energy of [7,103], we can infer that the chemical potential and magnetic field should have an influence on the running coupling.…”

Holographic imaginary potential of a quark antiquark pair in the presence of gluon condensation

“…by delving into the solution beyond the critical separation of the pair, which leads to the complex-valued string configurations, not the world-sheet thermal fluctuations method as we use here. In [52] the ImV Q Q of moving Q Q in a soft wall model with broken conformal invariance and finite chemical potential is discussed. As holographic examples, such as [49,[51][52][53] and [60] considered the moving cases, and they concluded that increasing rapidity leads to decreasing the dissociation length, implying the pair will be dissolved easier into a moving medium compared to the static medium, consistent with our findings here.…”

“…In [52] the ImV Q Q of moving Q Q in a soft wall model with broken conformal invariance and finite chemical potential is discussed. As holographic examples, such as [49,[51][52][53] and [60] considered the moving cases, and they concluded that increasing rapidity leads to decreasing the dissociation length, implying the pair will be dissolved easier into a moving medium compared to the static medium, consistent with our findings here. However, from EFT point of view, the reference [73] explored the in-medium modifications of heavy quarkonium states moving through a medium for two plausible situations:…”

Jet quenching parameter from a soft wall AdS/QCD model *

“…Further, this quantity has been investigated in some nonconformal settings [24][25][26]. Other interesting results can be found in [27][28][29][30][31][32][33][34][35].…”