1+1维弯曲时空中手征QCD_2的解

利用路径积分法我们给出了1+1维弯曲时空中手征QCD_2模型的有效拉氏量,证明了矢量玻色子可以有质量生成机制;除与正规化相关的质量项外,有效拉氏量还包含有与平直空间中相似的WZW项及规范均与引力场的相互作用项.     

1+1维弯曲时空中手征QCD2的解

利用路径积分法我们给出了1+1维弯曲时空中手征QCD₂模型的有效拉氏量,证明了矢量玻色子可以有质量生成机制;除与正规化相关的质量项外,有效拉氏量还包含有与平直空间中相似的WZW项及规范均匀与引力场的相互作用项.     

对称反常、非对称反常和有效拉氏量

本文进一步讨论作者利用Chern-Simons拓扑不变量建立的主手征模型的有效拉氏量, 指出非阿贝尔三角反常的对称形式和非对称形式都可以由此拉氏量得到.     

强作用与手征规范场

本文引入了e^{ia（x）r_s定域规范变换及相应的规范场.给出了手征规范不变的拉氏函数,并由此出发探讨了手征规范场与强相互作用的联系.在特定条件下可给出唯象的V-A强相互作用形式.}     

推导赝标Goldstone玻色子有效拉氏量

从QCD出发,未作近似推导出了赝标量Goldstone玻色子的有效手征拉氏量(ECL)理论.并以QCD中格林函数的形式给出了直到p⁴阶的ECL的系数的定义.     

SU(3)模型中夸克与手征场的相互作用

从SU(3)_L×SU(3)_R无穷小变换下不变拉氏量的线性表示形式出发,给出了夸克-夸克间的相互作用势.分析表明SU(3)标量手征场对解释AN相互作用中自旋关系的性质是很重要的.     

TC理论中矢量介子衰变研究

由TC理论的有效拉氏量,给出了矢量介子与标量介子相互作用顶角,讨论了中性矢量介子各种可能的衰变,并且具体计算了衰因子A.     

奇异拉氏量系统的正则对称性和Ward恒等式

给出了场论中约束Hamilton系统规范生成元的构成,说明了生成元中与第一类约束相联系的系数之间的关系.基于相空间中的生成泛函,导出了相应正则形式的Ward恒等式.讨论了与混合陈-Simons拉氏量等价的场论模型中的应用.     

从强子动力学模型看高温条件下核物质的新相

从QHD-Ⅱ模型的拉氏量出发,在有限温度场论的框架下,引入核子有效质量和有效化学势,给出了热力学势的平均场结果,分析了状态方程,发现在高温区核物质存在一个新的相变,最后给出了相图.     

热强子质量的有效手征拉氏量近似

从再现QCD标度反常的线性化手征拉氏量出发,使用热场动力学理论,计算了单圈近似下强子的热质量,并发现组分夸克质量和标量场质量在单圈近似下比在平均场近似下随温度的增加更快地下降,而在手征极限下,π介子在所有温度保持无质量.     

Effective Lagrangian Theory

From view point of modem field theory, all theories for realistic interaction are effective, which come from some more elementary theory. One main feature of effective theory is that it include infinite number of interaction terms. Effective theory is different with standard renormalizable field theory. Here, we focus on a class of special effective theory-effective chiral Lagrangian in strong interaction, discuss its features and present status of its development. We don't involve heavy quark effechvefield theory and N'RQCD and the combinahon of these theories and effective chiral Lagrangian.     

Topological structure of the inter-band phase difference soliton in two-band superconductivity

Two-component superconductivity based on the two-band superconductor has a functional topology such as an inter-band phase difference soliton (i-soliton) to realize topological electronics (topolonics). Many gauge field theories are applied to investigate the topology of two-band superconductivity. To ease experimental and electronics applications, these theories should be refined. Weinberg–Salam theory and SU(2) (two-dimensional special unitary symmetry) gauge field theory are proper starting points. An effective extra force field because of the crystal structure and inter-band Josephson interaction, rather than spontaneous symmetry breaking, simplifies the conventional gauge field theory.     

Construction of gauge invariant effective nucleonic theories: Functional approach

Starting from relativistic quantum field theories, describing interacting nucleons and pions coupled to the dynamical electromagnetic field, the pion degrees of freedom are eliminated by means of functional integration. Apart from taking into account some operators perturbatively in e, e.g. the vacuum polarization, this procedure is exact, giving effective theories for nucleons and photons. The subsequent nonrelativistic reduction yields the corresponding nonrelativistic quantum field.theory. The latter is unique, irrespective of the precise form of the original nucleon-pion interaction. Nucleonic potentials and electromagnetic interactions are mutually consitent. Local gauge invariance is satisfied at any stage of the formal development.     

Structural properties of effective potential model by liquid state theories

This paper investigates the structural properties of a model fluid dictated by an effective inter-particle oscillatory potential by grand canonical ensemble Monte Carlo (GCEMC) simulation and classical liquid state theories.The chosen oscillatory potential incorporates basic interaction terms used in modeling of various complex fluids which is composed of mesoscopic particles dispersed in a solvent bath,the studied structural properties include radial distribution function in bulk and inhomogeneous density distribution profile due to influence of several external fields.The GCEMC results are employed to test the validity of two recently proposed theoretical approaches in the field of atomic fluids.One is an Ornstein-Zernike integral equation theory approach;the other is a third order + second order perturbation density functional theory.Satisfactory agreement between the GCEMC simulation and the pure theories fully indicates the ready adaptability of the atomic fluid theories to effective model potentials in complex fluids,and classifies the proposed theoretical approaches as convenient tools for the investigation of complex fluids under the single component macro-fluid approximation.     

Chiral models: Geometrical aspects

Two-dimensional classical chiral models of field theory are considered, the main attention being paid on geometrical aspects of such theories.A characteristic feature of these models is that the interaction is inserted not by adding the interaction Lagrangian to the free field Lagrangian, but has a purely geometrical origin and is related to the inner curvature of the manifold.These models are in many respects analogous to non-Abelian gauge theories and as became clear recently, they are also important for the superstring theory which nowadays is the most probable candidate for a truly unified theory of all interactions including gravitation.     

Covariant open string field theory on multiple Dp-branes

We study covariant open bosonic string field theories on multiple Dp-branes by using the deformed cubic string field theory, which is equivalent to string field theory in the proper-time gauge. Constructing the Fock space representations of the three-string vertex and the four-string vertex on multiple Dp-branes, we obtain the field theoretical effective action in the zero-slope limit. On multiple D0-branes, the effective action reduces to the Banks-Fishler-Shenker-Susskind(BFSS) matrix model. We also discuss the relation between open string field theory on multiple D-instantons in the zero-slope limit and the Ishibashi-Kawai-Kitazawa-Tsuchiya(IKKT) matrix model.The covariant open string field theory on multiple Dp-branes could be useful to study the non-perturbative properties of quantum field theories in(p+1)-dimensions in the framework of the string theory. The non-zero-slope corrections may be evaluated systematically by using covariant string field theory.     

Virtual-site correlation mean field approach to criticality in spin systems

We propose a virtual-site correlation mean field theory for dealing with interacting many-body systems. It involves a coarse-graining technique that terminates a step before the mean field theory: While mean field theory deals with only single-body physical parameters, the virtual-site correlation mean field theory deals with single- as well as two-body ones, and involves a virtual site for every interaction term in the Hamiltonian. We generalize the theory to a cluster virtual-site correlation mean field, that works with a fundamental unit of the lattice of the many-body system. We apply these methods to interacting Ising spin systems in several lattice geometries and dimensions, and show that the predictions of the onset of criticality of these models are generally much better in the proposed theories as compared to the corresponding ones in mean field theories.     

On the meaning of a non-renormalizable theory of gravitation

The renormalizability of quantum gravity remains an open question while it has been established recently that quantum gravity in the presence of standard sources is non-renormalizable. In view of traditional confusion and ambiguities surrounding non-renormalizable quantum field theories, it has been felt that physical theories must be renormalizable. Recently a new, nonperturbative view of non-renormalizable theories has been suggested that may have relevance for various interactions including gravity and various sources. In a path integral approach to quantum field theory such a view attributes ‘hard cores’ in the space of field histories to non-renormalizable interactions. Just as with more familiar ‘hard cores’, turning off the interaction does not completely remove all effects of the potential. Consequently the interacting theory is not even continuously connected to the usual free theory, but rather to an alternative ‘pseudo-free’ theory that incorporates the vestiges of the ‘hard cores’. Some insight into what is the significance and interpretation of non-renormalizable interactions can be gleaned from exactly soluble models. Application of this philosophy of non-renormalizable interactions is discussed for the gravitational field in interaction with some standard sources.     

Asymptotic Stability in Geometric σ–models

Geometric –models have been defined as purely geometric theories of scalar fields in interaction with gravity. By construction, these theories possess soliton solutions with topologically nontrivial scalar sectors. We perform a detailed analysis of the stability of the effective scalar field theory far from the soliton core. It is shown that the requirement for the asymptotic stability is consistent with the existence of massive, static, spherically symmetric soliton solutions.     

Asymptotic Completeness in a Class of Massless Relativistic Quantum Field Theories

This paper presents the first examples of massless relativistic quantum field theories which are interacting and asymptotically complete. These two-dimensional theories are obtained by an application of a deformation procedure, introduced recently by Grosse and Lechner, to chiral conformal quantum field theories. The resulting models may not be strictly local, but they contain observables localized in spacelike wedges. It is shown that the scattering theory for waves in two dimensions, due to Buchholz, is still valid under these weaker assumptions. The concepts of interaction and asymptotic completeness, provided by this theory, are adopted in the present investigation.