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661.
A. S. Umar V. E. Oberacker J. A. Maruhn 《The European Physical Journal A - Hadrons and Nuclei》2008,37(2):245-250
We analyze the details of mass exchange in the vicinity of the Coulomb barrier for heavy-ion collisions involving neutron-rich
nuclei using the time-dependent Hartree-Fock (TDHF) theory. We discuss the time dependence of transfer and show that the potential
barriers seen by individual single-particle states can be considerably different than the effective barrier for the two interacting
nuclei having a single center of mass. For this reason we observe a substantial transfer probability even at energies below
the effective barrier. 相似文献
662.
663.
664.
The Structure of Corings: Induction Functors, Maschke-Type Theorem, and Frobenius and Galois-Type Properties 总被引:5,自引:0,他引:5
Tomasz Brzeziński 《Algebras and Representation Theory》2002,5(4):389-410
Given a ring A and an A-coring C, we study when the forgetful functor from the category of right C-comodules to the category of right A-modules and its right adjoint –
A
C are separable. We then proceed to study when the induction functor –
A
C is also the left adjoint of the forgetful functor. This question is closely related to the problem when A
A
Hom(C,A) is a Frobenius extension. We introduce the notion of a Galois coring and analyse when the tensor functor over the subring of A fixed under the coaction of C is an equivalence. We also comment on possible dualisation of the notion of a coring. 相似文献
665.
666.
667.
Manuel Breuning. 《Mathematics of Computation》2004,73(246):881-898
We consider a conjecture of Bley and Burns which relates the epsilon constant of the equivariant Artin -function of a Galois extension of number fields to certain natural algebraic invariants. For an odd prime number , we describe an algorithm which either proves the conjecture for all degree dihedral extensions of the rational numbers or finds a counterexample. We apply this to show the conjecture for all degree dihedral extensions of . The correctness of the algorithm follows from a finiteness property of the conjecture which we prove in full generality.
668.
O.Yu. Shvedov 《Journal of Functional Analysis》2004,210(2):259-294
The problem of specification of self-adjoint operators corresponding to singular bilinear forms is very important for applications, such as quantum field theory and theory of partial differential equations with coefficient functions being distributions. In particular, the formal expression corresponds to a non-trivial self-adjoint operator ? in the space only if d?3. For spaces of larger dimensions (this corresponds to the strongly singular case), the construction of ? is much more complicated: first one should consider the space as a subspace of a wider Pontriagin space, then one implicitly specifies ?. It is shown in this paper that Schrodinger, parabolic and hyperbolic equations containing the operator ? can be approximated by explicitly defined systems of evolution equations of a larger order. The strong convergence of evolution operators taking the initial condition of the Cauchy problem to the solution of the Cauchy problem is proved. 相似文献
669.
Gracinda M. S. Gomes 《Acta Mathematica Hungarica》2005,109(1-2):33-51
Summary We consider proper (idempotent pure) extensions of weakly left ample semigroups. These are extensions that are injective in
each <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>\widetilde{\mathcal{R}}$-class.
A graph expansion of a weakly left ample semigroup S is shown to be such an extension of S. Using semigroupoids acted upon by weakly left ample semigroups, we prove that any weakly left ample semigroup which is a
proper extension of another such semigroup T is (2,1)-embeddable into a λ-semidirect product of a semilattice by T. Some known results, by O'Carroll, for idempotent pure extensions of inverse semigroups and, by Billhardt, for proper extensions
of left ample semigroups follow from this more general situation. 相似文献
670.
The equations and , called Pexider equations, have been completely solved on If they are assumed to hold only on an open region, they can be extended to (the second when is nowhere 0) and solved that way. In this paper their common generalization is extended from an open region to and then completely solved if is not constant on any proper interval. This equation has further interesting particular cases, such as and that arose in characterization of geometric and power means and in a problem of equivalence of certain utility representations, respectively, where the equations may hold only on an open region in Thus these problems are solved too.