我们用半经典方法确定了$R^{3}\times S^{1}$上具有伴随标量的SU(2)规范理论的相结构。有两种全局对称性:与希格斯场相关的$Z(2)_{H}$对称性和$Z(2)_{C}$中心对称性。我们分析了当使用不同的变形项时,退细化相变的顺序。在找到全局对称性的序参量后,我们发现有四个不同的相:一个去限制相,一个限制相,一个希格斯相,和一个混合限制相。混合受限相出现在人们可能期望的一个相,其中既有限制和希格斯机制,但序参量的行为区分这两个阶段。在混合受限相中,$Z(2)_{C}\times Z(2)_{H}$整体对称性自发破缺为Z(2)子群,该子群对标量场和Polyakov圈都起非平凡作用。在BPS极限下,我们明确地找到了欧几里德场方程的BPS解和KK-BPS解。在混合相中,$ϕ$和$A_{4}$的线性组合进入到水溶液中。在所有四个阶段,威尔逊环正交的紧凑方向预计将显示面积定律的行为。我们表明,这种限制行为可以归因于一个广泛的区域,其中包括所有四个阶段的部分稀释气体。一个类似于最近[Poppitz and Unsal,2011]应用于$R^3 \times S^1$上的Seiberg-Witten模型的对偶性论证表明,使用欧几里得瞬子方法得到的氘气图像可以解释为有限能量的双子气体。
英文摘要:
We determine the phase structure of an SU(2) gauge theory with an adjoint scalar on $R^{3}\times S^{1}$ using semiclassical methods. There are two global symmetries: a $Z(2)_{H}$ symmetry associated with the Higgs field and a $Z(2)_{C}$ center symmetry. We analyze the order of the deconfining phase transition when different deformation terms are used. After finding order parameters for the global symmetries, we show that there are four distinct phases: a deconfined phase, a confined phase, a Higgs phase, and a mixed confined phase. The mixed confined phase occurs where one might expect a phase in which there is both confinement and the Higgs mechanism, but the behavior of the order parameters distinguishes the two phases. In the mixed confined phase, the $Z(2)_{C}\times Z(2)_{H}$ global symmetry breaks spontaneously to a Z(2) subgroup that acts non-trivially on both the scalar field and the Polyakov loop. We find explicitly the BPS and KK monopole solutions of the Euclidean field equations in the BPS limit. In the mixed phase, a linear combination of $ϕ$ and $A_{4}$ enters into the monopole solutions. In all four phases, Wilson loops orthogonal to the compact direction are expected to show area-law behavior. We show that this confining behavior can be attributed to a dilute monopole gas in a broad region that includes portions of all four phases. A duality argument similar to that applied recently [Poppitz and Unsal, 2011] to the Seiberg-Witten model on $R^3 \times S^1$ shows that the monopole gas picture, arrived at using Euclidean instanton methods, can be interpreted as a gas of finite-energy dyons.
We propose a novel description for the Higgs mechanism by which a gauge boson acquires the mass. We do not assume spontaneous breakdown of gauge symmetry signaled by a non-vanishing vacuum expectation value of the scalar field. In fact, we give a manifestly gauge-invariant description of the Higgs mechanism in the operator level, which does not rely on spontaneous symmetry breaking. This enables us to discuss the confinement-Higgs complementarity from a new perspective. The "Abelian" dominance in quark confinement of the Yang-Mills theory is understood as a consequence of the gauge-invariant H…
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We propose a gauge-invariant description for the Higgs mechanism by which a gauge boson acquires the mass. We do not need to assume spontaneous breakdown of gauge symmetry signaled by a non-vanishing vacuum expectation value of the scalar field. In fact, we give a manifestly gauge-invariant description of the Higgs mechanism in the operator level, which does not rely on spontaneous symmetry breaking. For concreteness, we discuss the gauge-Higgs models with $U(1)$ and $SU(2)$ gauge groups explicitly. This enables us to discuss the confinement-Higgs complementarity from a new perspective.
Gauge-independent transition separating confinement and Higgs phases in lattice SU(2) gauge theory with a scalar field in the fundamental representation
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In SU($N$) gauge-Higgs theories, with a single Higgs field in the fundamental representation, there exists in addition to the local gauge symmetry a global SU(2) symmetry, at $N=2$, and a global U(1) symmetry, for $N \ne 2$. We construct a gauge-invariant order parameter for the breaking of these global symmetries in the Higgs sector, and calculate numerically the transition lines, in coupling-constant space, for SU(2) and SU(3) gauge theories with unimodular Higgs fields. The order parameter is non-local, and therefore its non-analyticity does not violate the theorem proved by Osterwalder and…
We re-examine by numerical simulation the phase structure of the three-dimensional Abelian lattice gauge theory (LGT) with $Z(2)$ gauge fields coupled to $Z(2)$-valued Higgs fields. Concretely, we explore two different order parameters which are able to distinguish the three phases of the theory: (i) the Fredenhagen-Marcu operator used to discriminate between deconfinement and confinement/Higgs phases and (ii) the Greensite-Matsuyama overlap operator proposed recently to distinguish confinement and Higgs phases. The latter operator is an analog of the overlap Edwards-Anderson order parameter f…
We discuss the conditions under which Higgs and confining regimes in gauge theories with fundamental representation matter fields can be sharply distinguished. It is widely believed that these regimes are smoothly connected unless they are distinguished by the realization of global symmetries. However, we show that when a $U(1)$ global symmetry is spontaneously broken in \emph{both} the confining and Higgs regimes, the two phases can be separated by a phase boundary. The phase transition between the two regimes may be detected by a novel topological vortex order parameter. We first illustrate …
In the previous works, we proposed atomic quantum simulations of the U(1) gauge-Higgs model by ultra-cold Bose gases. By studying extended Bose-Hubbard models (EBHMs) including long-range repulsions, we clarified the locations of the confinement, Coulomb and Higgs phases. In this paper, we study the EBHM with nearest-neighbor repulsions in one and two dimensions at large fillings by the Gutzwiller variational method. We obtain phase diagrams and investigate dynamical behavior of electric flux from the gauge-theoretical point of view. We also study if the system exhibits glassy quantum dynamics…
Odd Toric Code in a tilted field: Higgs-confinement multicriticality, spontaneous self-duality symmetry breaking, and valence bond solids
Racah Institute of Physics, The Hebrew University of Jerusalem(耶路撒冷希伯来大学拉卡物理研究所);Max Planck Institute of Quantum Optics(马克斯·普朗克量子光学研究所);Munich Center for Quantum Science and Technology (MCQST)(慕尼黑量子科学与技术中心);The Fritz Haber Research Center for Molecular Dynamics, The Hebrew University of Jerusalem(耶路撒冷希伯来大学弗里茨·哈伯分子动力学研究中心)
We examine the phase structure of massive Yang-Mills theory in 1+1 dimensions. This theory is equivalent to a gauged principal chiral sigma model. It has been previously shown that the gauged theory has only a confined phase, and no Higgs phase in the continuum, and at infinite volume. There are no massive gluons, but only hadron-like bound states of sigma-model particles. The reason is that the gluon mass diverges, being proportional to the two-point correlation function of the renormalized field of the sigma model at $x=0$. We use exact large-$N$ results to show that after introducing a latt…
By using the gauge-invariant but path-dependent, variables formalism, we consider a recently proposed topologically massive $U{\left( 1 \right)_{\cal W}} \times U{(1)_{\cal Y}}$ Chern-Simons-Higgs theory in $2+1$ dimensions. In particular, we inspect the impact of a Chern-Simons mixing term between two Abelian gauge fields on physical observables. We pursue our investigation by analysing the model in two different situations. In the first case, where we integrate out the massive excitation and consider an effective model for the massless field, we show that the interaction energy contains a li…
This work presents concisely the results obtained from the analysis of the two-point function of the gauge field in the $SU(2)$ and $SU(2)\times U(1)$ gauge theories, in the Landau gauge, coupled to a scalar Higgs field in the fundamental or adjoint representation. Non-perturbative effects are considered by taking into account the Gribov ambiguity. In general, in both Yang-Mills models the gluon propagator has non-trivial contributions of physical and non-physical modes, which clearly depends on the group representation of the Higgs field. These results were presented during the Fourth Winter …
In this review, we provide a short outlook of some of the currently most popular pictures and promising approaches to non-perturbative physics and confinement in gauge theories. A qualitative and by no means exhaustive discussion presented here covers such key topics as the phases of QCD matter, the order parameters for confinement, the central vortex and monopole pictures of the QCD vacuum structure, fundamental properties of the string tension, confinement realisations in gauge-Higgs and Yang-Mills theories, magnetic order/disorder phase transition among others.
We study the Z_N symmetry in SU(N)+Higgs theories with the Higgs field in the fundamental representation. The distributions of the Polyakov loop show that the Z_N symmetry is explicitly broken in the Higgs phase. On the other hand, inside the Higgs symmetric phase the Polyakov loop distributions and other physical observables exhibit the Z_N symmetry. This effective restoration of the Z_N symmetry changes the nature of the confinement-deconfinenement transition. We argue that the Z_N symmetry will lead to time independent topological defect solutions in the Higgs symmetric deconfined phase whi…
The abelian Higgs model and its phase structure are discussed from the perspective that the gauge and scalar fields admit a dual description in terms of fermion variables. The results which indicate the presence of three main phases: Coulomb, Higgs and confinement agree well with those in the literature although a nonstandard order parameter is employed.
The dynamics of a cosmological (de)confinement phase transition is studied in nearly conformally invariant field theories, where confinement is predominantly spontaneously generated and associated with a light "dilaton" field. We show how the leading contribution to the transition rate can be computed within the dilaton effective theory. In the context of Composite Higgs theories, we demonstrate that a simple scenario involving two renormalization-group fixed points can make the transition proceed much more rapidly than in the minimal scenario, thereby avoiding excessive dilution of matter abu…
Motivated by the ideas of Jacob Bekenstein concerning gravity-assisted symmetry breaking, we consider a non-canonical model of f(R)=R+R^2 extended gravity coupled to neutral scalar "inflaton", as well as to SU(2)xU(1) multiplet of fields matching the content of the bosonic sector of the electroweak particle model, however with the following significant difference - the SU(2)xU(1) iso-doublet Higgs-like scalar enters here with a standard positive mass squared and without quartic selfinteraction. Strong interaction dynamics and, in particular, QCD-like confinement effects are also considered by …
Aspects of screening and confinement are re-examined for a recently proposed compact Abelian Higgs model with a $θ$-term. Our discussion is accomplished using the gauge-invariant but path-dependent variables formalism, which is an alternative to the Wilson loop approach. We explicitly show that the static potential profile is the sum of an effective-Yukawa and a linear potential, leading to the confinement of static external charges. We point out the central rôle of the parameter measuring the stiffness of the vortex lines present in the model in both the Yukawa-like and the confining sectors …