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91.
Soliton physics has made considerable progress in solving nonlinear problems. This paper is meant to relate the soliten concept to the stationary axisymmetric vacuum fields in general relativity. We present a functional transformation which, working as a nonlinear creation operator, generates gravitational fields of isolated sources. When applied to flat space-time (gravitational vacuum) this operation leads to a nonlinear superposition of an arbitrary number of Kerr particles. This superposition also includes the Tomimatsu-Sato fields. The functional transformations form an infinite-parameter group which contains the Kinnersley-Geroch group as a subgroup.This essay received the second award from the Gravity Research Foundation for the year 1980.-Ed.  相似文献   
92.
The yield curve of the reaction56Fe(p,γ)57Co has been measured over the energy rangeE p =1,300–1,900 keV and the decay of nine resonances has been investigated. For twelve of the resonances the strengths have been determined. The angular distributions of the gamma rays have been recorded for resonances atE p =1,599, 1,623, 1,643 and 1,649 keV, giving spin-parity assignmentsJ π=3/2? for all four resonances. The resonances atE p =1,623, 1,643 and 1,649 keV have been identified as the split analogue resonances of the 367 (J π=3/2?) states in57Fe. TheM1 transition strengths to the corresponding antianalogue states have been measured and compared with theoretical predictions.  相似文献   
93.
Letf be a meromorphic function of infinite order,T(r, f) its Nevanlinna (or Ahlfors-Shimizu) characteristic, andM(r, f) its maximum modulus. It is proved that $$\mathop {\lim \inf }\limits_{r \to \infty } \frac{{\log M(r,f)}}{{rT'(r,f)}} \leqslant \pi and\mathop {\lim \inf }\limits_{r \to \infty } \frac{{\log M(r,f)}}{{T(r,f)\psi (log T(r,f))}} = 0$$ . if ? (x)/x is non-decreasing, ?′(x)<-√?(x) and ∝ dx/?(x) < ∞.  相似文献   
94.
LetN(Z) denote the number of electrons which a nucleus of chargeZ can bind in non-relativistic quantum mechanics (assuming that electrons are fermions). We prove thatN(Z)/Z1 asZ.Research partially supported by the NSERC under Grant NA7901 and by the USNSF under Grants DMS-8416049 and PHY 85-15288-A01  相似文献   
95.
We study the pattern of soft parton radiation in the hard annihilation processes \(e^ + e^ - \to q\bar q\gamma \) and \(e^ + e^ - \to q\bar qg\) by explicit evaluation of the cross sections for \(e^ + e^ - \to q\bar q\gamma g\) and \(e^ + e^ - \to q\bar qgg + q\bar qq\bar q\) taken care of correct normalization. We find the coherence effects as observed experimentally and discuss why these effects are not present in the usual models based onO s 2 ) perturbation theory with subsequent independent fragmentation.  相似文献   
96.
Instability of nonlinear bound states   总被引:17,自引:0,他引:17  
We establish a sharp instability theorem for the bound states of lowest energy of the nonlinear Klein-Gordon equation,u ttu+f(u)=0, and the nonlinear Schrödinger equation, –iu tu+f(u)=0.Supported in part by NSF Grants MCS 81-21487 and MCS 82-01599  相似文献   
97.
A simple proof of a generalization of the theorem of Israel concerning the uniqueness of the Reissner-Nordström black holes is presented. The present method is also applied to show, in the bosonic sector ofN=4-supergravity, the uniqueness of a static black hole solution found by Gibbons.Work supported by Fonds zur Förderung der wissenschaftlichen Forschung in Österreich, Project No. 4961.  相似文献   
98.
The beta endpoint energies of the alkaline fission products88–94Rb and139–144Cs have been measured with an intrinsic Ge-detector at the OSTIS fission product separator. The linearity and high resolution of the detector yields an accuracy of up to a few keV. Additional beta gamma coincidence spectra allow the deduction of Qβ-values.  相似文献   
99.
The Curie temperatures (TC) and the hyperfine interactions of amorphous Fe40Ni40PyB20?y(0≤y>≤20) have been determined by 57Fe Mössbauer spectroscopy. In this series of amorphous solid with a fixed transition-metal content, the metalloid atoms are shown to have a noticeable effect on TC, isomer shift and hyperfine field distribution.  相似文献   
100.
The Cauchy Problem for the relativistic Vlasov-Maxwell equations is studied in three space dimensions. It is assumed that the initial data satisfy the required constraints and have compact support. If in addition the data have sufficiently smallC 2 norm, then a uniqueC 1 solution to this system is shown to exist on all of spacetime.Research supported in part by NSF DMS 85-20662 and NSF DMS 84-20957  相似文献   
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