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11.
Geometric (Clifford) algebra provides an efficient mathematical language for describing physical problems. We formulate general relativity in this language. The resulting formalism combines the efficiency of differential forms with the straightforwardness of coordinate methods. We focus our attention on orthonormal frames and the associated connection bivector, using them to find the Schwarzschild and Kerr solutions, along with a detailed exposition of the Petrov types for the Weyl tensor. 相似文献
12.
The XYZ model describes the interaction between nuclear probes and an electric field gradient that fluctuates among three orthogonal
directions. The model presents a means to calculate the perturbation function that represents spectra obtained using perturbed
angular correlation spectroscopy. Three analytic approximations of the perturbation function have been developed previously,
and they are evaluated in the present paper in the context of Cd jumping among In-lattice sites in In3La. 相似文献
13.
Matthew D. Horton 《Linear algebra and its applications》2007,425(1):130-142
After defining and exploring some of the properties of Ihara zeta functions of digraphs, we improve upon Kotani and Sunada’s bounds on the poles of Ihara zeta functions of undirected graphs by considering digraphs whose adjacency matrices are directed edge matrices. 相似文献
14.
15.
M. Ferro-Luzzi Z.-L. Zhou J.F.J. van den Brand H.J. Bulten J. Lang H.R. Poolman 《Hyperfine Interactions》1997,110(3-4):239-257
We present data showing hyperfine transitions in an atomic deuterium beam induced by the (476 MHz) radio-frequency field of
a 704 MeV electron beam in a storage ring. A polarized deuterium beam, produced in an atomic beam source, was crossed with
a stored electron beam and analyzed with a Breit--Rabi polarimeter. Electron-beam induced transitions were singled out by
injecting different combinations of hyperfine states. Transition probabilities as high as 70% were measured at large currents
(~ 100 mA). All possible deuterium transitions for a radio-frequency of 476 MHz were observed. In addition, a 1--6 transition
resulting from the first harmonic (952 MHz) was observed.
The effects of these transitions are of general importance for the polarized internal target technique applied in nuclear
and particle physics experiments. The data are reasonably described by numerical estimates. The observed mechanism can be
exploited to create nuclear polarized atoms when injecting electron polarized atoms with no net nuclear polarization into
a storage cell. However, when nuclear polarized atoms are injected, care should be taken to avoid this mechanism, since it
would result in depolarization of the atoms. The studies enabled us to choose the magnetic guide field during our spin-dependent
electron--deuteron scattering experiments, such that electron-beam induced depolarizing effects were avoided.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
16.
We demonstrate that the 3-power torsion points of the Jacobians of the principal modular curves X(3n) are fixed by the kernel of the canonical outer Galois representation of the pro-3 fundamental group of the projective line
minus three points. The proof proceeds by demonstrating the curves in question satisfy a two-part criterion given by Anderson
and Ihara. Two proofs of the second part of the criterion are provided; the first relies on a theorem of Shimura, while the
second uses the moduli interpretation.
Received: 30 September 2005 相似文献
17.
Lui Lam Flonnie Dowell Helmut Brand Guenter Ahlers 《Journal of statistical physics》1991,64(5-6):899-901
18.
Radical reaction of a series of N-(2-bromoallyl)arylcarboxamides led to the production of 4-arylpyrrolidin-2-ones and directly reduced materials in comparable yields. A cascade process, involving sequential 5-exo-trig spirocyclisation, β-scission, and 5-endo-trig cyclisation of the resulting acyl radical, is proposed to explain the pyrrolidinone products. 相似文献
19.
Suppose F is a field of characteristic p?5, and that B is a p-block of the symmetric group Sn of defect 3. We prove that the Ext1-quiver of B is bipartite, with the bipartition being described in a simple way using the leg-lengths of p-hooks of partitions. 相似文献
20.