Intrinsic Thickness of QCD Flux-Tubes

通量管的内在宽度作为探索格点规范理论中禁闭机制的工具

Intrinsic Width of the Flux Tube as a tool to explore confining mechanisms in Lattice Gauge Theories

通过研究SU(2)规范模型在2+1维中通量管的内在宽度，检验不同禁闭模型，发现高温下Ising有效模型适用，低温下双超导模型拟合较好但Ginzburg-Landau参数随管长增加，表明需要更复杂的模型。

Flux tube delocalization at the deconfinement point

We study the behaviour of the flux tube thickness in the vicinity of the deconfinement transition. We show, using effective string methods, that in this regime the square width increases linearly and not logarithmically with the interquark distance. The amplitude of this linear growth is an increasing function of the temperature and diverges as the deconfinement transition is approached from below. These predictions are in good agreement with a set of simulations performed in the 3d gauge Ising model.

Azimuthal fermionic current in the cosmic string spacetime induced by a magnetic tube

In this paper, we analyze the vacuum azimuthal fermionic current induced by a magnetic field confined in a cylindrical tube of finite radius $a$, in the cosmic string spacetime. Three distinct configurations for the magnetic field are taken into account: (i) a cylindrical shell of radius $a$, (ii) a magnetic field proportional to $1/r$ and (iii) a constant magnetic field. In these three cases, the axis of the infinitely long tube of radius $a$ coincides with the cosmic string; moreover, we only develop this analysis for the region outside the tube. In order to do that, we explicitly construct …

Induced fermionic current by a magnetic tube in the cosmic spacetime

In this paper, we consider a charged massive fermionic quantum field in the space-time of an idealized cosmic string, in the presence of a magnetic field confined in a cylindrical tube of finite radius. Three distinct configurations for the magnetic field is taken into account: (i) a cylindrical shell of radius $a$, (ii) a magnetic field proportional to $1/r$ and (iii) a constant magnetic field. In these three cases, the axis of the infinitely long tube of radius $a$ coincides with the cosmic string. Our main objective is to analyze the induced vacuum fermionic current densities outside the tu…

Yang-Mills flux tubes的拓扑结构

Topological structure of the entanglement radius of Yang-Mills flux tubes

本文研究了Yang-Mills理论中磁通管的拓扑结构，揭示了纠缠半径ξ₀的物理意义及其在纠缠熵计算中的作用。

Soliton Junctions in the Large Magnetic Flux Limit

We study the flux tube junctions in the limit of large magnetic flux. In this limit the flux tube becomes a wall vortex which is a wall of negligible thickness (compared to the radius of the tube) compactified on a cylinder and stabilized by the flux inside. This wall surface can also assume different shapes that correspond to soliton junctions. We can have a flux tube that ends on a wall, a flux tube that ends on a monopole and more generic configurations containing all three of them. In this paper we find the differential equations that describe the shape of the wall vortex surface for these…

Chromo-field flux sheets as confining gauge field configurations in the SU(N) Euclidean Yang-Mills theory in the Landau gauge

For the four-dimensional SU(N) Euclidean Yang-Mills theory in the Landau gauge, we present two sets of gauge field configurations that satisfy the Euclidean equations of motion. These configurations generate four-dimensional chromo-field flux sheets whose spatial cross sections are three-dimensional chromo-field flux tubes. In lattice simulations, they may be detected as center vortices. The first set of gauge field configurations generates chromo-electric flux tubes that should contribute to a chromo-electric flux tube between two static color charges. The string tension for two static color …

Spin-String Interaction in QCD Strings

I consider the question of the interaction between a QCD string and the spin of a quark or an antiquark on whose worldline the string terminates. The problem is analysed from the point of view of a string representation for the expectation value of a Wilson loop for a spin-half particle. A string representation of the super Wilson loop is obtained starting from an effective string representation of a Wilson Loop. The action obtained in this manner is invariant under a worldline supersymmetry and has a boundary term which contains the spin-string interaction. For rectangular loops the spin-stri…

Domain Walls and Flux Tubes

We present a new vortex solution made of a domain wall compactified into a cylinder and stabilized by the magnetic flux within. When the thickness of the wall is much less than the radius of the vortex some precise results can be obtained, such as the tension spectrum and profile functions. This vortex can naturally end on the wall that has created it, making the simplest junction between a wall and a vortex. We then classify every kind of junction between a flux tube and domain wall. The criteria for classification are as follows: a flux can or can not end on the wall, and when it ends, the f…

A New Constraint on Effective Field Theories of the QCD Flux Tube

Effective magnetic $SU(N)$ gauge theory with classical $Z_N$ flux tubes of intrinsic width $\frac{1}{M}$ is an effective field theory of the long distance quark-antiquark interaction in $SU(N)$ Yang-Mills theory. Long wavelength fluctuations of the $Z_N$ vortices of this theory lead to an effective string theory. In this paper we clarify the connection between effective field theory and effective string theory and we propose a new constraint on these vortices. We first examine the impact of string fluctuations on the classical dual superconductor description of confinement. At inter-quark dist…

Effective string action for the U(1)xU(1) dual Ginzburg-Landau theory beyond the London limit

The effective string action of the color-electric flux tube in the U(1) x U(1) dual Ginzburg-Landau (DGL) theory is studied by performing a path-integral analysis by taking into accountthe finite thickness of the flux tube. The DGL theory, corresponding to the low-energy effective theory of Abelian-projected SU(3) gluodynamics, can be expressed as s [U(1)]^{3} dual Abelian Higgs (DAH) model with a certain constraint in the Weyl symmetric formulation. This formulation allows us to adopt quite similar path-integral techniques as in the U(1) DAH model, and therefore, the resulting effective strin…

Quantum broadening of k-strings in gauge theories

We study the thickness of the confining flux tube generated by a pair of sources in higher representations of the gauge group. Using a simple geometric picture we argue that the area of the cross-section of the flux tube, as measured by a Wilson loop probe, grows logarithmically with source separation, as a consequence of the quantum fluctuations of the underlying k-string. The slope of the logarithm turns out to be universal, i.e. it is the same for all the representations and all the gauge theories. We check these predictions in a 3D Z_4 lattice gauge model by comparing the broadening of the…

Critical Boundary Conditions for the Effective String

Gauge systems in the confining phase induce constraints at the boundaries of the effective string, which rule out the ordinary bosonic string even with short distance modifications. Allowing topological excitations, corresponding to winding around the colour flux tube, produces at the quantum level a universal free fermion string with a boundary phase nu=1/4. This coincides with a model proposed some time ago in order to fit Monte Carlo data of 3D and 4D Lattice gauge systems better. A universal value of the thickness of the colour flux tube is predicted.

驱动无碰撞重联的力自由磁通管：从起始到合并

Driven Collisionless Reconnection of Force-free Flux Tubes: From Onset to Coalescence

研究通过二维粒子-细胞模拟，探讨了驱动无碰撞重联和等离子体束形成的过程，发现电流片厚度与皮肤深度相当，长宽比A大于30时等离子体链发展，重联率约为0.1。

在具有诺伊曼边界条件的不可穿透磁管背景下量子带电标量物质的感应真空能量密度

Induced vacuum energy density of quantum charged scalar matter in the background of an impenetrable magnetic tube with the Neumann boundary condition

本研究计算了不可穿透磁管外带电标量场的真空极化，发现诺伊曼边界条件下感应真空能量密度大于狄利克雷情况，并表现出阿哈罗诺夫-玻姆周期性。

Evidence for Negative Stiffness of QCD Strings

QCD strings are color-electric flux tubes between quarks with a finite thickness and thus a finite curvature stiffness. Contrary to an earlier rigid-string by Polyakov and Kleinert, and motivated by the properties of a magnetic flux tubes in type-II superconductors we put forward the hypothesis that QCD strings have a {\em negative\/ stiffness. We set up a new string model with this property and show that it is free of the three principal problems of rigid-strings --- particle states with negative norm, nonexistence of a lowest-energy state, and wrong high-temperature behavior of string tensio…

Quantum Fusion of Strings (Flux Tubes) and Domain Walls

We consider formation of composite strings and domain walls as a result of fusion of two elementary objects (elementary strings in the first case and elementary walls in the second) located at a distance from each other. The tension of the composite object T_2 is assumed to be less than twice the tension of the elementary object T_1, so that bound states are possible. If in the initial state the distance d between the fusing strings or walls is much larger than their thickness and satisfies the conditions T_1 d^2 >> 1 (in the string case) and T_1 d^3 >> 1 (in the wall case), the problem can be…