We study the response of confining gauge theory to the external electric field by using holographic Yang-Mills theories in the large $N_c$ limit. Although the theories are in the confinement phase, we find a transition from the insulator to the conductor phase when the electric field exceeds its critical value. Then, the baryon number current is generated in the conductor phase. At the same time, in this phase, the meson melting is observed through the quasi-normal modes of meson spectrum. Possible ideas are given for the string state corresponding to the melted mesons, and they lead to the idea that the source of this current may be identified with the quarks and anti-quarks supplied by the melted mesons. We also discuss about other possible carriers. Furthermore, from the analysis of the massless quark, chiral symmetry restoration is observed at the insulator-conductor transition point by studying a confining theory in which the chiral symmetry is broken.
Holographic Krylov complexity in confining gauge theories
Institute for Theoretical and Mathematical Physics, Lomonosov Moscow State University（莫斯科国立大学理论与数学物理研究所）；Instituto de Física Teórica, UNESP-Universidade Estadual Paulista（圣保罗州立大学理论物理研究所）；Centre for Quantum Fields and Gravity, Department of Physics, Swansea University（斯旺西大学物理系量子场与引力中心）；Department of Physics, Indian Institute of Technology Roorkee（鲁尔基印度理工学院物理系）
Holographic Krylov spread complexity for a confining multi-charge AdS soliton
Instituto de Física Teóretica, UNESP - Universidade Estadual Paulista（圣保罗州立大学理论物理研究所）；Centre for Quantum Fields and Gravity, Department of Physics, Swansea University（斯旺西大学物理学院量子场与引力中心）
In the context of theories with a first order phase transition, we propose a general covariant description of coexisting phases separated by domain walls using an additional order parameter-like degree of freedom. In the case of a holographic Witten model with a confining and deconfined phase, the resulting model extends hydrodynamics and has a simple formulation in terms of a spacetime action with corresponding expressions for the energy-momentum tensor. The proposed description leads to simple analytic profiles of domain walls, including expressions for surface tension density, which agree n…
Universal aspects of holographic Schwinger effect in general backgrounds
我们考虑了具有均匀电场的一般背景中全息施温格效应的普遍性。这个论点是基于我们以前的工作中开发的潜在分析。在某些条件下，总是存在一个临界电场，超过该电场，势垒消失，系统变得灾难性地不稳定。临界值与由Dirac Born Infeld作用量得到的临界值一致。对于一般的束缚背景，我们证明了当电场弱于束缚弦张力时，不会出现施温格效应。
For two symmetric strips with equal and finite size and in the background of several confining geometries, we numerically calculate the critical distance between these two mixed systems where the mutual information between them drops to zero and show that this quantity could be a useful correlation measure in probing the phase structures of holographic QCD models. The models that we consider here are Sakai-Sugimoto and deformed Sakai-Sugimoto, Klebanov-Tseytlin and Maldacena Nunez. For evaluating the structures of these holographic supergravity geometries from the perspective of the bulk recon…
We study rectangular timelike Wilson loops at long distances in the exact renormalization group flow in the context of the holographic duality. We consider the 5d holographic model with an exponential dilaton potential constructed in [arXiv:1803.06764]. To probe the RG flow backgrounds at zero and finite temperatures we calculate the minimal surfaces of the corresponding string worldsheets. We show that a holographic RG flow at $T=0$, that mimics QCD behaviour of the running coupling, has a confining phase at long distances, while the RG flow with an AdS UV fixed point is non-confining.
Using the gauge-gravity duality, we study the holographic Schwinger effect by performing the potential analysis on the confining D3- and D4-brane background with D-instantons then evaluate the pair production/decay rate by taking account into a fundamental string and a single flavor brane respectively. The two confining backgrounds with D-instantons are obtained from the black D(-1)-D3 and D0-D4 solution with a double Wick rotation. The total potential and pair production/decay rate in the Schwinger effect are calculated numerically by examining the NG action of a fundamental string and the DB…
Using holography, we discuss the effects of an external static electric field on the D3/D-instanton theory at zero-temperature, which is a quasi-confining theory, with confined quarks and deconfined gluons. We introduce the quarks to the theory by embedding a probe D7-brane in the gravity side, and turn on an appropriate $U(1)$ gauge field on the flavor brane to describe the electric field. Studying the embedding of the D7-brane for different values of the electric field, instanton density and quark masses, we thoroughly explore the possible phases of the system. We find two critical points in…
The low-energy effective theory description of a confining theory, such as QCD, is constructed including local interactions between hadrons organized in a derivative expansion. This kind of approach also applies more generically to theories with a mass gap, once the relevant low energy degrees of freedom are identified. The strength of local interactions in the effective theory is determined by the low momentum expansion of scattering amplitudes, with the scattering length capturing the leading order. We compute the main contribution to the scattering length between two spin-zero particles in …
Single quarks moving in the vacuum of confining gauge theories are stopped by a drag force. The holographic description relates the confining scale in the bulk geometry with a range of physical values for the drag force in the vacuum. The vacuum drag force acting on the isolated quark directly manifests quark confinement since it prevents the quark from walking freely in the vacuum. However, analytical expressions for the drag force as a function of the quark velocity were lacking. In the present work, we propose that the vacuum drag force is given by the regularized zero-temperature limit of …
Confining Properties of Abelian(-Projected) Theories
导出了阿贝尔投影SU（2）-和SU（3）-胶子动力学的磁流表示。除二次项外，所得到的有效作用量还包含了这些电流与四维电弦世界面或三维电涡旋线的相互作用。其次，我们证明了3D紧致QED是具有外磁单极子的3D Abel Higgs模型的小规范玻色子质量极限，并给出了约束弦论作为量子密度积分的物理解释。最后，我们导出了三维紧致QED弱场极限下的双局域场强度关联式，结果与随机真空模型预言的结果一致。
