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1.
A formulation of composite electrodynamics, with scalar singleton constituents, is here extended to a supersymmetric theory of composite photons and neutrinos, in which the (massless) neutrinos are composed of one each of the scalar and spinorial singletons. These particles interact with an arbitrary scalar matter superfield, with massive, charged components. The feasibility of an interaction that is gauge invariant (in the sense of singleton gauge invariance) arises from the use of unconventional quantization rules which, in turn, are available because singletons are kinematically confined.  相似文献   

2.
《Nuclear Physics B》1986,274(2):448-474
The Wess-Zumino consistency condition is verified explicitly for the anomaly of a single chiral superfield coupling to a background scalar superfield, using the expression for the anomaly obtained by a direct perturbative calculation. The proof is next extended to a verification of the whole set of Piguet-Sibold equations.  相似文献   

3.
Residual dipolar couplings (RDCs) between NC′ and NCα atoms in polypeptide backbones of proteins contain information on the orientation of bond vectors that is complementary to that contained in NH RDCs. The 1JNCα and 2JNCα scalar couplings between these atoms also display a Karplus relation with the backbone torsion angles and report on secondary structure. However, these N–C couplings tend to be small and they are frequently unresolvable in frequency domain spectra having the broad lines characteristic of large proteins. Here a TROSY-based J-modulated approach for the measurement of small 15N–13C couplings in large proteins is described. The cross-correlation interference effects inherent in TROSY methods improve resolution and signal to noise ratios for large proteins, and the use of J-modulation to encode couplings eliminates the need to remove frequency distortions from overlapping peaks during data analysis. The utility of the method is demonstrated by measurement of 1JNC′, 1JNCα, and 2JNCα scalar couplings and 1DNC′ and 1DNCα residual dipolar couplings for the myristoylated yeast ARF1·GTPγs protein bound to small lipid bicelles, a system with an effective molecule weight of 70 kDa.  相似文献   

4.
In the projective theory of relativity the 5-dimensional field equation \(_{\mu \nu } \) and the resulting equation of motion Tμυ = 0 are investigated. There Tμυ stands for the 5-dimensional tensor of macroscopic matter. The 4-dimensional field equations and equation of motion obtained by projection are a generalization of Einstein's theory of general relativity and Maxwell's electrodynamics, involving a scalar field φ.They contain a single constant φ0.The weak field approximation is investigated for the case of an ideal fluid and leads to Newton's mechanics, including Newton's gravitational law, and to Maxwell's electrodynamics. For the constant φ0 one obtains the approximate value φ0c4N with Newton's gravitational constant γN.For homogeneous and isotropic cosmological models consisting of matter only the general solution for the radius K of curvature is given. This solution is independent of the equation of state of matter For a pure dust universe the general solution for the scalar field φ is given. For a closed universe a power law φ ?K?1 is valid which leads to Mach's principle. The calculation of the age of a closed universe yields over 7×109y,if one uses mean values of the present cosmological data.  相似文献   

5.
We examine the exact relation between the superconformal symmetry breaking chiral superfield (X) and the goldstino superfield in microscopic models of an arbitrary Kahler potential (K) and in the presence of matter fields. We investigate the decoupling of the massive sgoldstino and scalar matter fields and the offshell/onshell-SUSY expressions of their superfields in terms of the fermions composites. For general K of two superfields, we study the properties of the superfield X after integrating out these scalar fields, to show that in the infrared it satisfies (offshell) the condition X3=0 and X2≠0. We then compare our results to those of the well-known method of constrained superfields discussed in the literature, based on the conjecture X2=0. Our results can be used in applications, to couple offshell the (s)goldstino fields to realistic models such as the MSSM.  相似文献   

6.
We give a general SU(2) L × SU(2) R × U(1) EM sigma model with external sources, dynamical breaking and spontaneous vacuum symmetry breaking, and present the general formulation of the model. It is found that σ and π0 without electric charges have electromagnetic interaction effects coming from their internal structures. A general Lorentz transformation relative to external sources is derived, using the general Lorentz transformation and the four-dimensional current of nuclear matter of the ground state with J gauge = 0, we give the four-dimensional general relations between the different currents of nuclear matter systems with J gauge≠ 0 and those with J gauge = 0. The relation of the density’s coupling with external magnetic field is derived, which conforms well to dense nuclear matter in a strong magnetic field. We show different condensed effects in strong interaction about fermions and antifermions, and give the concrete scalar and pseudoscalar condensed expressions of σ0 and π0 bosons. About different dynamical breaking and spontaneous vacuum symmetry breaking, the concrete expressions of different mass spectra are obtained in field theory. This paper acquires the running spontaneous vacuum breaking value σ′0, and obtains the spontaneous vacuum breaking in terms of the running σ′0, which make nucleon, σ and π particles gain effective masses. We achieve both the effect of external sources and nonvanishing value of the condensed scalar and pseudoscalar paticles. It is deduced that the masses of nucleons, σ and π generally depend on different external sources. PACA numbers: 24.10.-i, 11.30.Qc  相似文献   

7.
By the application of a linear mass spectrum to a composite system of both the pseudoscalar and scalar meson nonets, we find three relations for the masses of the scalar states which suggest the assignment for the scalar meson nonet a0(1320), K 0 * (1430), f0(1500), and f0 (980).  相似文献   

8.
The derivation of the exact and unique nilpotent Becchi–Rouet–Stora–Tyutin (BRST) and anti-BRST symmetries for the matter fields, present in any arbitrary interacting gauge theory, has been a long-standing problem in the framework of the superfield approach to the BRST formalism. These nilpotent symmetry transformations are deduced for the four (3+1)-dimensional (4D) complex scalar fields, coupled to the U(1) gauge field, in the framework of an augmented superfield formalism. This interacting gauge theory (i.e. QED) is considered on a six (4,2)-dimensional supermanifold parametrized by four even spacetime coordinates and a couple of odd elements of the Grassmann algebra. In addition to the horizontality condition (that is responsible for the derivation of the exact nilpotent symmetries for the gauge field and the (anti-)ghost fields), a new restriction on the supermanifold, owing its origin to the (super) covariant derivatives, has been invoked for the derivation of the exact nilpotent symmetry transformations for the matter fields. The geometrical interpretations for all the above nilpotent symmetries are discussed, too. PACS 11.15.-q, 12.20.-m, 03.70.+k  相似文献   

9.
It is shown how the static-gauge world-volume superfield actions of diverse superbranes on the AdSd+1 superbackgrounds can be systematically derived from nonlinear realizations of the appropriate AdS supersymmetries. The latter are treated as superconformal symmetries of flat Minkowski superspaces of the bosonic dimension d. Examples include the N = 1 AdS4 supermembrane, which is associated with the 1/2 partial breaking of the OSp(1|4) supersymmetry down to the N = 1, d = 3 Poincaré supersymmetry, and the T-duality related L3-brane on AdS5 and scalar 3-brane on AdS5 × S1, which are associated with two different patterns of 1/2 breaking of the SU(2, 2|1) supersymmetry. Another (closely related) topic is the AdS/CFT equivalence transformation. It maps the world-volume actions of the codimension-one AdSd+1 (super)branes onto the actions of the appropriate Minkowski (super)conformal field theories in the dimension d.  相似文献   

10.
By studying the scattering process of scalar particle pion on the noncommutative scalar quantum electrodynamics, the non-commutative amendment of differential scattering cross-section is found, which is dependent of polar-angle and the results are significantly different from that in the commutative scalar quantum electrodynamics, particularly when cosθ∼±1. The non-commutativity of space is expected to be explored at around ΛNC∼TeV.  相似文献   

11.
We study the two-point correlation function of a freely decaying scalar in Kraichnan's model of advection by a Gaussian random velocity field that is stationary and white noise in time, but fractional Brownian in space with roughness exponent 0<<2, appropriate to the inertial-convective range of the scalar. We find all self-similar solutions by transforming the scaling equation to Kummer's equation. It is shown that only those scaling solutions with scalar energy decay exponent a(d/)+1 are statistically realizable, where d is space dimension and =2–. An infinite sequence of invariants J p, p=0, 1, 2,..., is pointed out, where J 0 is Corrsin's integral invariant but the higher invariants appear to be new. We show that at least one of the invariants J 0 or J 1 must be nonzero (possibly infinite) for realizable initial data. Initial datum with a finite, nonzero invariant—the first being J p—converges at long times to a scaling solution p with a=(d/)+p, p=0, 1. The latter belongs to an exceptional series of self-similar solutions with stretched-exponential decay in space. However, the domain of attraction includes many initial data with power-law decay. When the initial datum has all invariants zero or infinite and also it exhibits power-law decay, then the solution converges at long times to a nonexceptional scaling solution with the same power-law decay. These results support a picture of a two-scale decay with breakdown of self-similarity for a range of exponents (d+)/<a<(d+2)/, analogous to what has recently been found in the decay of Burgers turbulence.  相似文献   

12.
The critical properties of an XY helimagnet on a square lattice with two chiral order parameters are studied by Monte Carlo simulations. This model is a modification of the J 1-J 2-J 3 model with J 2 = 0. The case of different third range order interactions J 3 are considered, J 3 a ?? J 3 b . A first order transition is found away from the Lifshitz points 4J 3 a = J 1 and 4 J 3 b = J 1. It is pointed out that a chiral spin liquid phase possibly exists near the Lifshitz points.  相似文献   

13.
The most general form of electrodynamics has been derived by Sachs [1] from the irreducible representations of the Einstein group. In this paper the Sachs theory is developed as a gauge theory with a vacuum four-current i j . The B Cyclic Theorem O(3) electrodynamics is derived from a consideration of four-vectors appearing in the Sachs theory, and electromagnetic helicity, expressed in terms of the B (3) field of O(3) electrodynamics, is derived from the more general Sachs theory.  相似文献   

14.
In the present work, it is shown that a chameleon scalar field having a non-minimal coupling with dark matter can give rise to a smooth transition from a decelerated to an accelerated phase of expansion for the Universe. It is surprising to note that the coupling with the chameleon scalar field hardly affects the evolution of the dark matter sector, which still redshifts as a .  相似文献   

15.
A two-dimensional HSQC-based NMR method, 15N-COSMO-HSQC, is presented for the rapid determination of homonuclear 3JHNHα couplings in 15N-labeled proteins in solution. Scalar couplings are extracted by comparing the intensity of two separate datasets recorded with and without decoupling of the 3JHNHα during a preparation period. The scalar couplings are introduced through a cosine modulation of the peak intensities. The experiment relies on a BIRD sandwich to selectively invert all amide protons HN and is very simple to implement. 3JHNHα couplings were determined using both the 15N-COSMO-HSQC and quantitative-J on 15N-labeled chemokine RANTES. The two experiments show well-correlated values.  相似文献   

16.
The mechanisms of processes determining distribution of positive ions on the cathode surface in a discharge with oscillating electrons are studied. At low pressures P≤5×10−5 torr over the entire range of anode length variation l a=0.5–11 cm, the ion current distribution over the cathode radius J i(r) features a single maximum in the center and drops steeply with distance from the axis. At pressures P=1–4×10−4 torr, the distribution J i(r) for short anodes (l a<6 cm) is similar to the previous one but, for long anodes (l a=6–10 cm), new maxima at higher J i values have been detected. A physical explanation for the obtained results is proposed.  相似文献   

17.
We study the ground state properties of a one-dimensional Ising chain with a nearest-neighbor ferromagnetic interactionJ 1, and akth neighboranti-ferromagnetic interactionJ k . WhenJ k/J1=–1/k, there exists a highly degenerate ground state with a residual entropy per spin. For the finite chain with free boundary conditions, we calculate the degeneracy of this state exactly, and find that it is proportional to the (N+k–1)th term in a generalized Fibonacci sequence defined by,F N (k) =F N–1 (k) +F N–k (k) . In addition, we show that this one-dimensional model is closely related to the following problems: (a) a fully frustrated two-dimensional Ising system with a periodic arrangement of nearest-neighbor ferro- and antiferromagnetic bonds, (b) close-packing of dimers on a ladder, a 2× strip of the square lattice, and (c) directed self-avoiding walks on finite lattice strips.Work partially supported by grants from AFOSR and ARO.  相似文献   

18.
Some modification of source terms is proposed for gauge field theories. In theSU(2) Yang-Mills theory with arbitrary external sources a canonical quantization procedure leads to a Lorentz-invariantS-matrix only when Fermi statistics is imposed on ghost fields. The usual source terms lead to a result that breaks Lorentz invariance and is singular when external chargesJskin0 vanish. The cases of the Abelian scalar electrodynamics and theSU(2) Yang-Mills field with external currents (Jskino=0,Jskini 0) are also discussed.  相似文献   

19.
We present a modified formulation of minimal N = 1 linearized supergravity coupled to generic N = 1 supersymmetric matter. The formalism is based on the superprojectors, superspin-transition operators, vector and scalar superfield. Such approach has some advantages for finding superpropagators. Presented at the International Colloquium “Integrable Systems and Quantum Symmetries”, Prague, 16–18 June 2005.  相似文献   

20.
We perform numerical simulations of the 2-d Heisenberg antiferromagnet using a cluster algorithm. Comparing the size and temperature effects of various quantities with results from chiral perturbation theory we determine the low energy parameters of the system very precisely. We finde 0=–0.6693(1)J/a 2 for the ground state energy density, s = 0.3074(4)/a 2 for the staggered magnetization,c=1.68(1)J a for the spin wave velocity andp s =0.186(4)J for the spin stiffness. Our results agree with experimental data for the precursor insulators of high-T c superconductors.Supported by the Schweizer Nationalfond  相似文献   

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