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141.
Matthias Birkner José Alfredo Ló pez-Mimbela Anton Wakolbinger 《Proceedings of the American Mathematical Society》2002,130(8):2431-2442
We present a probabilistic approach which proves blow-up of solutions of the Fujita equation in the critical dimension . By using the Feynman-Kac representation twice, we construct a subsolution which locally grows to infinity as . In this way, we cover results proved earlier by analytic methods. Our method also applies to extend a blow-up result for systems proved for the Laplacian case by Escobedo and Levine (1995) to the case of -Laplacians with possibly different parameters .
142.
Orbital angular momentum entangled photons emitted by a down-conversion source are in higher dimensional entangled states. Here we report the experimental confirmation by demonstrating a violation of a generalized Clauser-Horne-Shimony-Holt-type Bell inequality in three dimensions by more than 18 standard deviations. Higher dimensional entangled states allow the realization of new types of quantum communication protocols. They also provide a more secure quantum cryptography scheme. Therefore our experimental results are likely to have applications in future quantum communication technology. 相似文献
143.
Brezger B Hackermüller L Uttenthaler S Petschinka J Arndt M Zeilinger A 《Physical review letters》2002,88(10):100404
We demonstrate a near-field Talbot-Lau interferometer for C70 fullerene molecules. Such interferometers are particularly suitable for larger masses. Using three free-standing gold gratings of 1 microm period and a transversally incoherent but velocity-selected molecular beam, we achieve an interference fringe visibility of 40% with high count rate. Both the high visibility and its velocity dependence are in good agreement with a quantum simulation that takes into account the van der Waals interaction of the molecules with the gratings and are in striking contrast to a classical moiré model. 相似文献
144.
First full-relativistic density functional calculations with the extension of the spin-polarization functional for the relativistic density functional theory in their collinear and noncollinear form are presented here for the molecular system Pt2. The agreement with experiment is very good. 相似文献
145.
146.
Dedication
For Daniel Greenberger on His 65th Birthday 相似文献147.
Extreme Estimates for Interpolated Operators by the Real Method 总被引:3,自引:0,他引:3
The paper establishes estimates for ideal measures of operatorsinterpolated by the real method in terms of the measures oftheir restrictions to a sequence of spaces modelled on the intersection.It also shows that the estimates are optimal. 相似文献
148.
Anton L Hilfer R 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,59(6):6819-6823
We discuss the problem of trapping and mobilization of nonwetting fluids during immiscible two-phase displacement processes in porous media. Capillary desaturation curves give residual saturations as a function of capillary number. Interpreting capillary numbers as the ratio of viscous to capillary forces the breakpoint in experimental curves contradicts the theoretically predicted force balance. We show that replotting the data against a novel macroscopic capillary number resolves the problem for discontinuous mode displacement. 相似文献
149.
Anton Bovier Michael Eckhoff Véronique Gayrard Markus Klein 《Communications in Mathematical Physics》2002,228(2):219-255
We study a large class of reversible Markov chains with discrete state space and transition matrix P
N
. We define the notion of a set of metastable points as a subset of the state space Γ
N
such that (i) this set is reached from any point x∈Γ
N
without return to x with probability at least b
N
, while (ii) for any two points x, y in the metastable set, the probability T
− 1
x
,
y
to reach y from x without return to x is smaller than a
N
− 1< b
N
. Under some additional non-degeneracy assumption, we show that in such a situation:
(i) To each metastable point corresponds a metastable state, whose mean exit time can be computed precisely.
(ii) To each metastable point corresponds one simple eigenvalue of 1 −P
N
which is essentially equal to the inverse mean exit time from this state. Moreover, these results imply very sharp uniform
control of the deviation of the probability distribution of metastable exit times from the exponential distribution.
Received: 1 August 2000 / Accepted: 19 November 2001 相似文献
150.