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1.
We show that subtraction of the Möbius group volume in the open string massless amplitudes can be realized as a renormalization of linear 2D ultraviolet divergences in the generating functional (“partition function”). This implies that the vector field effective action can be represented as a renormalized partition function (i.e. as a path integral of the “Wilson factor”). We check this by computing several leading terms in the non-abelian effective action.  相似文献   

2.
《Physics letters. [Part B]》1988,213(2):160-164
We systematically study the gauge fixing of the Möbius and the super-Möbius transformations for the N-point closed-string amplitudes on the disk. Using the Faddeev-Popov method, we obtain the explicit formulas for the Koba-Nielsen factors for these amplitudes.  相似文献   

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We study the finite-size scaling properties of the Ising model on the M?bius strip and the Klein bottle. The results are compared with those of the Ising model under different boundary conditions, that is, the free, cylindrical, and toroidal boundary conditions. The difference in the magnetization distribution function p(m) for various boundary conditions is discussed in terms of the number of the percolating clusters and the cluster size. We also find interesting aspect-ratio dependence of the value of the Binder parameter at T = T(c) for various boundary conditions. We discuss the relation to the finite-size correction calculations for the dimer statistics.  相似文献   

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Abstract

The spectral analysis of the Schrödinger operator on cubic lattice type graphs is developed. Similarly to the quantum mechanical tight-binding approximation, using the well known concept of the Dirichlet-to-Neumann map, asymptotic formulae for localized negative spectral bands of the Schrödinger operator on a periodic metric graph are established. The results are illustrated by numerical calculations.  相似文献   

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Abstract

The Hilbert space representations of a class of commutation relations associated with a Möbius transformation is studied using results on convergence of continued fractions.  相似文献   

8.
《Physics letters. A》1999,259(2):108-114
Closed-form expressions are obtained for the generating function of close-packed dimers on a 2M×2N simple quartic lattice embedded on a Möbius strip and a Klein bottle. Finite-size corrections are also analyzed and compared with those under cylindrical and free boundary conditions. Particularly, it is found that, for large lattices of the same size and with a square symmetry, the number of dimer configurations on a Möbius strip is 70.2% of that on a cylinder. We also establish two identities relating dimer generating functions for Möbius strips and cylinders.  相似文献   

9.
The Möbius transformation (MT) was analyzed as a coordinate transformation in the Minkowski form. The transformation function contains three separate light cones. The Weyl spheres were interpreted as basic constituents of local light cones. These cones are related to the denominators of the MT and its inverse, and their apexes define an axis with the top of the global light cone as the centerpoint. That axis represents the local part of the world-line of a moving frame of reference. On the world-line, the scale factor of the MT is proportional to the ratio of the radii of the initial Weyl sphere and the equivalent transformed one. The projection centers, defining the transformation of the world-line, were determined graphically. There are two types of such MT's. Inner transformations have their projetion centers on the axes of the frame at rest, outer transformations on the axes of the observed moving frame. The signature of x 0 2 –r2 is conserved during inner transformations. All possible directions of the world-line of an inertial frame form a timelike mass cone around the time axis of the frame at rest. The mass cone and the related spacelike phase cone may be seen as projections of a lightlike central motion on the surface of a Weyl sphere. Conformal transformations leave both the mass cone and the phase cone invariant: the MT locally, and the Lorentz transformation globally. The moving frame of any lightlike particle rotates by /2 radians, thus exchanging the time axis with one of the space axes. The measurable mass of such a particle is considered to be zero because only the central plane of the particle is space-oriented. The real mass is invariant. To test this hypothesis, the two -quanta produced by the electron pair annihilation should be led to a recollision, for recreating the initial electron-position pair.  相似文献   

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We experimentally observed a new topological symmetry in optical composites, namely, metamaterials. While it is not found yet in nature materials, the electromagnetic M?bius symmetry discovered in metamaterials is equivalent to the structural symmetry of a M?bius strip, with the number of twists controlled by the sign change of the electromagnetic coupling between the meta-atoms. We further demonstrate that metamaterials with different coupling signs exhibit resonance frequencies that depend only on the number but not the locations of the "twists," thus confirming its topological nature. The new topological symmetry found in metamaterials may enable unique functionalities in optical materials.  相似文献   

12.
A procedure described byBykov andHien is employed to obtain an approximation formula for the line broadening expected in a Mössbauer experiment for the case where the emission and absorption spectra have Gaussian shapes. For identical emission and absorption spectra, the broadening as given by this formula has an error of less than 4·5% for effective absorber thicknesses up toT A =10. The case where the emission and absorption spectra have different half widths is also considered.  相似文献   

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The coherent states for a quantum particle on a Möbius strip are constructed and the relation with the natural phase space for fermionic fields is shown. The explicit comparison of the obtained states with previous works where the cylinder quantization was used and the spin 1/2 was introduced by hand is given.  相似文献   

15.
We study the projective linear group PGL 2(A) associated with an arbitrary algebra A and its subgroups from the point of view of their action on the space of involutions in A. This action formally resembles M?bius transformations known from complex geometry. By specifying A to be an algebra of bounded operators in a Hilbert space H, we rediscover the M?bius group μ ev (M) defined by Connes and study its action on the space of Fredholm modules over the algebra A. There is an induced action on the K-homology of A, which turns out to be trivial. Moreover, this action leads naturally to a simpler object, the polarized module underlying a given Fredholm module, and we discuss this relation in detail. Any polarized module can be lifted to a Fredholm module, and the set of different lifts forms a category, whose morphisms are given by generalized M?bius tranformations. We present an example of a polarized module canonically associated with the differentiable structure of a smooth manifold V. Using our lifting procedure we obtain a class of Fredholm modules characterizing the conformal structures on V. Fredholm modules obtained in this way are a special case of those constructed by Connes, Sullivan and Teleman. Received: 2 October 1997 / Accepted: 11 August 1998  相似文献   

16.
A criterion is proposed for the choice of optimal absorber thickness. The effect of quadrupole splitting, self-absorption, and absorber thickness on the total absorption coefficient and the criterion Q is examined.Translated from Izvestiya Vysshikh Uchebnkh Zavedenii, Fizika, pp. 18–23, No. 1, January, 1986.  相似文献   

17.
Freund I 《Optics letters》2011,36(23):4506-4508
The twist numbers of circular optical M?bius strips and twisted ribbons are shown to obey the index theorem under rotation of the plane of observation, and under change in the radius of the path.  相似文献   

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Shuo Zhang  Nan-xian Chen 《哲学杂志》2013,93(12):1451-1461

Using Chen-Möbius lattice inversion, we derive the interionic pair potentials from pseudopotential total-energy curves of the RbCl polymorph. Based on the potentials, the B1-B2 transition pathways have been analysed by calculating the activation energy and saddle point at transition pressure. The intermediate structures along the transition path were obtained within the different symmetric restrictions. By comparing the four pathways under the different restricted conditions, the intermediate structures with space groups Cmcm and P2 1 / m were predicted to explain the B1-B2 phase transition in RbCl.  相似文献   

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