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1.
We investigate the possibility of transforming supersymmetric theories into pure;y fermionic or bosonic forms. The supersymmetric sine-Gordon lagrangian is rewritten in a purely fermionic form, and the Fermi equivalent of the original supersymmetry transformation is derived. This transformation represents an invariance only at the quantum level, when the effects of the chiral anomaly have been taken into account. When supersymmetric theories are written in purely bosonic forms, a non-local bosonic transformation takes place of the supersymmetry transformation. In both cases the supersymmetry algebra, as realized on the fields, is lost.  相似文献   

2.
One feature of the chiral anomaly, analyzed in a perturbative framework, is the appearance of massless poles which account for it. They are identified by a spectral analysis of the anomaly graph and are usually interpreted as being of an infrared origin. Recent investigations show that their presence is not just confined in the infrared, but that they appear in the effective action under the most general kinematical conditions, even if they decouple in the infrared. Further studies reveal that they are responsible for the non-unitary behaviour of these theories in the ultraviolet (UV) region. We extend this analysis to the case of the conformal anomaly, showing that the effective action describing the interaction of gauge fields with gravity is characterized by anomaly poles that give the entire anomaly and are decoupled in the infrared (IR), in complete analogy with the chiral case. This complements a related analysis by Giannotti and Mottola on the trace anomaly in gravity, in which an anomaly pole has been identified in the corresponding correlator using dispersion theory in the IR. Our extension is based on an exact computation of the off-shell correlation function involving an energy–momentum tensor and two vector currents (the gauge–gauge–graviton vertex) which is responsible for the appearance of the anomaly.  相似文献   

3.
The deuteron theory is renewed and completed for non-local Hamiltonians. A method to calculate deuteron wave functions is given. The formula for the current density and the magnetic dipole moment of a non-local potential is derived, and applied to the GCT, GT, and HJ-potential. The effects of a unitary transformation on the deuteron data — electric quadrupole moment, magnetic dipole moment, and radius — are shown. For the numerical calculations the Ristig-Kistler transformation and the HJ-potential were used. It is shown that an overall fit cannot be reached.  相似文献   

4.
李子平 《中国物理 C》1995,19(4):320-326
从系统的作用量在普遍的定域和非定域变换下的性质出发,导出了含非定城变换的广义Noether恒等式.将其用于高阶微商杨—Mills场论,求出了有别于BRS荷的新PBRS守恒荷和非定域变换下的新守恒荷.  相似文献   

5.
李子平 《中国物理 C》2002,26(12):1214-1222
基于高阶微商奇异拉氏量系统的相空间生成泛函,导出了定域和非定域变换下的量子正则Noether恒等式;对高阶微商规范不变系统,导出了位形空间中定域和非定域变换下的量子Noether恒等式.指出在某些情形下,由量子Noether恒等式可导致系统的量子守恒律.这种求守恒律的程式与量子Noether(第一)定理不同.用于高阶微商非AbelChern-Simons(CS)理论,求出某些非定域等变换下的量子守恒量.  相似文献   

6.
Starting from the transformation property of the action integral of a system under the local and non-local transformation, we derive the generalized Noether's identities connecting with non-local transformation. The applications of the theory to the Yang-Mills field with high-order derivatives are presented. A new conservative PBRS charge is found which differs from BRS conservative charge. The other conservative charge connecting with non-local transformation is also obtained.  相似文献   

7.
In this paper wave propagation in non-local elastic solids is examined in the framework of the mechanically based non-local elasticity theory established by the author in previous papers. It is shown that such a model coincides with the well-known Kröner-Eringen integral model of non-local elasticity in unbounded domains. The appeal of the proposed model is that the mechanical boundary conditions may easily be imposed because the applied pressure at the boundaries of the solid must be equilibrated by the Cauchy stress. In fact, the long-range forces between different volume elements are modelled, in the body domain, as central body forces applied to the interacting elements. It is shown that the shape change of travelling disturbances coalesces with those predicted by the non-local integral theory of elasticity in unbounded domains, but several differences arise in the case of bounded domains. The wave propagation problem has been formulated by means of the Hamiltonian functional of the proposed mechanically based model of non-local elasticity, introducing an additional term to the elastic potential energy that accounts for elastic long-range interactions. In this way, the wave equation may be obtained in a weak formulation and be further used to provide approximate analytical solutions to the governing equation in the context of standing wave analysis. An equivalent discrete point-spring model, similar to lattice-type networks, has also been introduced to show the mechanical equivalence of the non-local elastic model as well as to provide a mechanical scheme suitable for the numerical treatment of pressure waves travelling in non-local bounded domains.  相似文献   

8.
We are interested in deriving various full Green functions through general Ward–Takahashi identities (WTIs) for quantized field theories. With the help of a postulate of gauge group parameter, the general local gauge transformation laws preserving the gauge-invariance of the generating functional itself of QED model have been established successfully. By using path-integral technique, the various WTIs with resulting anomaly terms are derived under the gauge transformations. The arising of Jacobian factor from the integration measure gives a viable possibility to express full Green function. As a consequence, the complete expressions of the full vector, the full axial-vector, the full tensor vertex functions and so on are presented respectively by solving the complete set of the WTIs in the momentum space without considering the constraint imposing any Ansatz. In addition, anomaly function also provides an effective means to judge the divergence of variant coupling currents on fields.  相似文献   

9.
The amorphization mechanism of icosahedral Pt nanoclusters is investigated by a combination of molecular dynamics simulations and density functional calculations. A general mechanism for amorphization, involving rosettelike structural transformations at fivefold vertices, is proposed. In the rosette, a fivefold vertex is transformed into a hexagonal ring. We show that, for icosahedral Pt nanoclusters, this transformation is associated with an energy gain, so that their most favorable structures have a low symmetry even at icosahedral magic numbers, and that the same mechanism underlies the formation of amorphous structures in gold.  相似文献   

10.
Based on the phase-space generating functional of the Green function for a system with a regular/singular Lagrangian, the quantal canonical Noether identities (NI) under the local and non-local transformation in extended phase have been derived, respectively. The result holds true whether the Jacobian of the transformation is equal to unity or not. Based on the configuration-space generating functional of the gauge-invariant system obtained by using Faddeev-Popov (FP) trick, the quantal NI under the local and non-local transformation in configuration space have been also deduced. It is showed that for a system with a singular Lagriangian one must use the effective action in the quantal NI instead of the classical action in corresponding classical NI. It is pointed out that in certain cases, the quantal NI may be converted into the quantal (weak) conservation laws by using the quantal equations of motion. This algorithm to derive the quantal conservation laws differs from the quantal first Noether theorem. The preliminary applications of this formulation to Yang-Mills (YM) fields and non-Abelian Chern-Simons (CS) theories are given. The quantal conserved quantities for non-local transformation in YM fields are obtained. The conserved BRS and PBRS quantities at the quantum level in non-Abelian CS theories are also found. The property of fractional spin in CS theories is discussed. PACS no11.10. Ef; 11.30.−j 11.15. −q.  相似文献   

11.
S.Biri  E.Fekete  I.Iván  I.Gál 《中国物理 C》2007,31(Z1):156-158
In order to extend the capabilities of the ATOMKI-ECRIS it is being transformed into a modified plasma device by changing its three main components with new ones.The cylindrical plasma chamber is replaced by a larger one(ID=10cm,L=40cm).A new NdFeB multi-pole radial trap was designed and purchased.The basic configuration is 6-pole,but 8-or 12-pole arrangements can also be formed later.The Dresent microwave source(2000W,14.5GHz)and two additional low-power,wide frequency TWT amplifiers give many opportunities to form plasmas with different sizes and characters. Actually a new facility with two sharply different operation modes is being established.All the modifications are reversible so the transformation of the ECRIS into this new device or back can be easily done.  相似文献   

12.
A. Gaaff  J. Hijmans 《Physica A》1976,83(2):301-316
In a previous paper, the partition function of the 16-vertex model was shown to be invariant under a group of linear transformations in the space of the vertex weights. According to a theorem by Hilbert, every algebraic invariant such as the partition function for a finite lattice can be expressed algebraically in terms of a finite set of basic algebraic invariants, which are sums of products of the vertex weights. We construct this set by analysing the structural properties of the transformation group (the direct product of two three-dimensional orthogonal groups). The basic set is found to consist of 21 invariants, ranging from a linear invariant up to invariants of the ninth degree. In particular cases, notably the (general or the symmetric) eight-vertex model, the six-vertex model and the free-fermion model, several invariants vanish and a number of additional algebraic relations between the basic invariants are obtained.  相似文献   

13.
We discuss the local and non-local pion-nucleus optical potentials. We find that the local potential becomes non-local when two-nucleon correlations are included. The two potentials (including correlations) can be made local through a transformation on the wave function. The new local potentials agree up to quadratic terms when expanded in powers of the density. The influence of finite-range correlations and off-shell pion-nucleon form factors is also investigated.  相似文献   

14.
A field-enlarging transformation in chiral electrodynamics is performed. This introduces an additional gauge symmetry that is unitary and anomaly free and allows for comparison of different models discussed in the literature. The problem of superfluous degrees of freedom and their influence on quantization is discussed. Several so-called mysteries are explained from this point of view.  相似文献   

15.
《Nuclear Physics B》1998,516(3):623-651
A free field representation for the type I vertex operators and the corner transfer matrices of the eight-vertex model is proposed. The construction uses the vertex-face correspondence, which makes it possible to express correlation functions of the eight-vertex model in terms of correlation functions of the SOS model with a non-local insertion. This new non-local insertion admits a free field representation in terms of Lukyanov's screening operator. The spectrum of the corner transfer matrix and the Baxter-Kelland formula for the average staggered polarization have been reproduced.  相似文献   

16.
17.
《Nuclear Physics B》1996,460(2):362-378
We study the non-localization of extended worldsheet supersymmetry under T-duality, when the associated complex structure depends on the coordinate with respect to which duality is performed. First, the canonical transformation which implements T-duality is generalized to the supersymmetric non-linear σ-models. Then, we obtain the non-local object which replaces the complex structure in the dual theory and write down the condition it should satisfy so that the dual action is invariant under the non-local supersymmetry. For the target space, this implies that the supersymmetry transformation parameter is a non-local spinor. The analogue of the Killing equation for this non-local spinor is obtained. It is argued that in the target space the supersymmetry is no longer realized in the standard way. The string theoretic origin of this phenomenon is briefly discussed.  相似文献   

18.
薛希玲  陈汉武  刘志昊  章彬彬 《物理学报》2016,65(8):80302-080302
完全图KN 上某个顶点连接到图G将破坏其对称性. 为加速定位这类结构异常, 基于散射量子行走模型设计搜索算法, 首先给出了算法酉算子的定义, 在此基础上利用完全图的对称性, 将算法的搜索空间限定为一个低维的坍缩图空间. 以G为一个顶点的情况为例, 利用硬币量子行走模型上的研究结论简化了坍缩图空间中酉算子的计算, 并借助矩阵扰动理论分析算法演化过程. 针对星图SN 上结构异常的研究表明, 以星图中心节点为界将整个图分为左右两个部分, 当且仅当两部分在N→∞时具有相同的特征值, 搜索算法可以获得量子加速. 本文说明星图上的分析方法和结论可以推广至完全图的坍缩图上. 基于此, 本文证明无论完全图连接的图G结构如何, 搜索算法均可在O(√N) 时间内定位到目标顶点, 成功概率为1-O(1√N), 即量子行走搜索该类异常与经典搜索相比有二次加速.  相似文献   

19.
《Physics letters. A》2003,314(4):267-271
Entangled states of the W-class are considered as a quantum channel for teleportation of an entangled state and as well the state to be teleported via a multiparticle quantum channel. Using an introduced unitary transformation in the teleportation schemes based on the multiparticle Greenberger–Horne–Zeilinger channel it is found a set of protocols main feature of which is a collection of non-local recovering operators.  相似文献   

20.
Based on the phase-space generating functional of the Green function for a system with a regular/singular higher-order Lagrangian, the quantum canonical Noether identities (NIs) under a local and non-local transformation in phase space have been deduced, respectively. For a singular higher-order Lagrangian, one must use an effective canonical action IeffP in quantum canonical NIs instead of the classical IP in classical canonical NIs. The quantum NIs under a local and non-local transformation in configuration space for a gauge-invariant system with a higher-order Lagrangian have also been derived. The above results hold true whether or not the Jacobian of the transformation is equal to unity or not. It has been pointed out that in certain cases the quantum NIs may be converted to conservation laws at the quantum level. This algorithm to derive the quantum conservation laws is significantly different from the quantum first Noether theorem. The applications of our formulation to the Yang-Mills fields and non-Abelian Chern-Simons (CS) theories with higher-order derivatives are given, and the conserved quantities at the quantum level for local and non-local transformations are found, respectively.Received: 12 February 2002, Revised: 16 June 2003, Published online: 25 August 2003Z.-P. Li: Corresponding authorAddress for correspondence: Department of Applied Physics, Beijing Polytechnic University, Beijing 100022, P.R. China  相似文献   

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