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601.
Alexandru I. Nicolin Mogens H. Jensen Jan W. Thomsen R. Carretero-Gonzlez 《Physica D: Nonlinear Phenomena》2008,237(19):2476-2481
We consider the dynamics of a dilute, magnetically-trapped one-dimensional Bose–Einstein condensate whose scattering length is periodically modulated with a frequency that linearly increases in time. We show that the response frequency of the condensate locks to its eigenfrequency for appropriate ranges of the parameters. The locking sets in at resonance, i.e., when the effective frequency of driving field is equal to the eigenfrequency, and is accompanied by a sudden increase of the oscillations amplitude due to resonant energy transfer. We show that the dynamics of the condensate is given, to leading order, by a driven harmonic oscillator on the time-dependent part of the width of the condensate. This equation captures accurately both the locking and the resonant energy transfer as it is evidenced by comparison with direct numerical simulations of original Gross–Pitaevskii equation. 相似文献
602.
We prove that, for an inner form of GL
n
, the number of classes of cuspidal automorphic representations with fixed central character and fixed factor at almost every place is finite. We also prove, in the local situation, relations between the level and the -factor of an irreducible smooth representation. 相似文献
603.
Marian Vâ jâ itu Alexandru Zaharescu 《Proceedings of the American Mathematical Society》2002,130(12):3447-3452
Let be a real number, a positive integer and a subset of . We give an upper bound for the number of distinct lengths of gaps between the fractional parts .
604.
On the basis of endospectral graphs, we present a graphical method for obtaining pairs of nonisomorphic graphs with identical atomic counts of self-returning walks. 相似文献
605.
Hadi-Kh Mahabadi Lupu Alexandru 《Journal of polymer science. Part A, Polymer chemistry》1990,28(2):231-243
Due to the particular rheological properties of thermotropic liquid crystalline polymers (TLCP), their application for imaging technology has been investigated. The first class of polymers investigated in this study are the thermotropic liquid crystalline polycarbonates prepared from the solution polycondensation of p,p-dihydroxybiphenyl with bischloroformate as the aliphatic flexible spacer. From the variety of bischloroformates employed, smectic TLCP's were generally obtained with the possible presence of a nematic mesostate. The introduction of comonomers such as substituted hydroquinones or bisphenols were found to lower both the melting transitions and mesophasic range of the TLCP. From rheological characterization, the amount of nonmesogenic moieties present in the copolycarbonates were found to correlate with the increase in the melt viscosity of TLCP. 相似文献
606.
607.
608.
We estimate the norm of the almost Mathieu operator , regarded as an element in the rotation C*-algebra . In the process, we prove for every λ∈R and the inequality
609.
The Correlations of Farey Fractions 总被引:1,自引:0,他引:1
It is proved that all correlations of the sequence of Fareyfractions exist and explicit formulas are provided for the correlationmeasures. 相似文献
610.
George E. Andrews Bruce C. Berndt Jaebum Sohn Ae Ja Yee Alexandru Zaharescu 《Transactions of the American Mathematical Society》2003,355(6):2397-2411
The continued fraction in the title is perhaps the deepest of Ramanujan's -continued fractions. We give a new proof of this continued fraction, more elementary and shorter than the only known proof by Andrews, Berndt, Jacobsen, and Lamphere. On page 45 in his lost notebook, Ramanujan states an asymptotic formula for a continued fraction generalizing that in the title. The second main goal of this paper is to prove this asymptotic formula.