摘要:

AbstractClassical nucleation theory is applied to follow the thermal history of a homogeneous and isotropic universe during a first‐order phase transition. The dependence of possible supercooling and reheating scenarios on the surface tension and growth velocity of bubbles is discusse

ISSN:0004-6337    

DOI:10.1002/asna.2113090602

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090603

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractIn gravitational theories of 4‐th order, the influence of certain properties of the field equations (tracelessness, conformal invariance, scale in variance respectively their breaking) for the “particle content” (number of degrees of freedom, mass, spin) is investigated. Using the plane‐wave ansatz valid in linearized theory it is possible to determine the mass content of the theory, but one cannot get assertions about the number of degrees of freedom and the spin states corresponding to the field quanta. In the linearized theory, this can be done with a spin projection formalism.Using the Cauchy initial value problem and a counting method first developed by EINSTEIN one can get, however, a useful definition of the concept of the degrees of freedom for the full nonlinear theory. This is due to the fact that this method allows to incorporate the concrete structure of the field equations (and thus their nonlinearities). Analysing different general‐relativistic field theories via these approaches the influence of the various structures of nonlinearities is discussed. It is, in particular, shown that those results obtained by the spin projection formalism can be reproduced by “nonline

ISSN:0004-6337    

DOI:10.1002/asna.2113090604

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractCorrelation studies of the pattern of time variation of the recorded solar neutrino flux monitored through the reaction Cl37→ Ar37with various parameters of solar activity is suggestive of possible emission of a penetrating neutral particle from the sun influencing directly or indirectly the transformation Cl37→ Ar37deep underground at the required rates. This possibility has to be invoked in view of the difficulties in generating the observed pattern of variations through a large modulatory mechanism involving the electron neutrino. The prediction that follows is the possible existence of a time varying component (diurnal) in the rate of some nuclear transmutations deep underground caused by an unknown neutral radiation having an interaction cross section with matter probably much larger than the canonical value of 10‐36cm2per nucleon speculated upon by some authors in the WIMP scenario for th

ISSN:0004-6337    

DOI:10.1002/asna.2113090605

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090607

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractWe compare and interpret distributions of vertical electric current densities derived from nearly simultaneous vector measurements by the magnetographs of the Sayan Observatory (Irkutsk) and the Potsdam Solar Observatory. The derived distributions of current densities of the different observations are in good agreement referring to the scaling factors and the morphological structure. The zero points differ within the noise level amounting to 0.8*10‐3Am‐2for the Sayan observation and to 1.3*10‐3Am‐2for the Potsdam observation. In the spot under study we found several current filaments indicating that the spot is clustered by several flux bundles. An azimuthal current between (5.9 ± 1.4)*1011A and (6.8 ± ± 1.5)*1011A flowing around a (relatively isolated) flux bundle can be derived from the ob

ISSN:0004-6337    

DOI:10.1002/asna.2113090608

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090610

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090612

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0004-6337    

DOI:10.1002/asna.2113090601

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY