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91.
This article deals with empty spacetime and the question of its physical reality. By “empty spacetime” we mean a collection of bare spacetime points, the remains of ridding spacetime of all matter and fields. We ask whether these geometric objects—themselves intrinsic to the concept of field—might be observable through some physical test. By taking quantum-mechanical notions into account, we challenge the negative conclusion drawn from the diffeomorphism invariance postulate of general relativity, and we propose new foundational ideas regarding the possible observation—as well as conceptual overthrow—of this geometric ether. 相似文献
92.
A. I. Sakhanenko 《Siberian Mathematical Journal》2006,47(6):1113-1127
We obtain estimates for the distributions of errors which arise in approximation of a random polygonal line by a Wiener process on the same probability space. The polygonal line is constructed on the whole axis for sums of independent nonidentically distributed random variables and the distance between it and the Wiener process is taken to be the uniform distance with an increasing weight. All estimates depend explicitly on truncated power moments of the random variables which is an advantage over the earlier estimates of Komlos, Major, and Tusnady where this dependence was implicit. 相似文献
93.
94.
A simple two ordinary lens system is proposed to realize the fractional Fourier transform (FRT) of continuously variable order while keeping the scaling factors of both the input and output functions as the same constant independent of the geometric parameters of the system and the FRT orders. It can remove the necessity and inconvenience of using input masks of different scales or any other special devices, and then is helpful to those who want to observe the FRT but have no specific facilities. 相似文献
95.
双环形振子的超对称性 总被引:3,自引:0,他引:3
研究了双环形振子(DRSO)的超对称性和形不变性,并得到了DRSO的能量本征值和能量本征函数 相似文献
96.
D. Ferger 《Acta Appl Math》2003,78(1-3):115-120
We prove a functional law of the iterated logarithm for U-statistics type processes. The result is used to determine the almost sure set of limit points for change-point estimators. 相似文献
97.
A. Bershadskii 《Journal of statistical physics》1997,89(3-4):869-875
The Havlin-Bunde multifractal hypothesis [Physica D
38:184 (1989)] is expanded (in the form of the dimension-invariance approach) to nonlinear iterative (recursion) processes such
as dielectric breakdown, phase transitions from periodic attractors to chaos, and cascades in turbulence. Comparison with
model and laboratory data of different authors shows that for strong nonlinearity the dimension invariance is broken 相似文献
98.
In this paper, we study the weak invariance of the multidimensional rank statistic when the underlying random variables are nonstationary absolutely regular. 相似文献
99.
We study the partition function for the low-energy edge excitations of the incompressible electron fluid. On an annular geometry, these excitations have opposite chiralities on the two edges; thus, the partition function takes the standard form of rational conformal field theories. In particular, it is invariant under modular transformations of the toroidal geometry made by the angular variable and the compact Euclidean time. The Jain series of plateaus have been described by two types of edge theories: the minimal models of the W1+∞ algebra of quantum area-preserving diffeomorphisms, and their non-minimal version, the theories with
affine algebra. We find modular invariant partition functions for the latter models. Moreover, we relate the Wen topological order to the modular transformations and the Verlinde fusion algebra. We find new, non-diagonal modular invariants which describe edge theories with extended symmetry algebra; their Hall conductivities match the experimental values beyond the Jain series. 相似文献
100.
Partition functions of critical 2D models on a torus can be derived from their microscopic formulation and their free field representation in the continuum limit. This is worked out explicitly for theO(n) andQ-state Potts model. Forn orQ integer we recover results obtained from conformal invariance, but our procedure also extends to nonintegral values. In the latter case the expansion on characters of the Virasoro algebra involves real coefficients of either sign. The operator content of both models is discussed in detail. 相似文献