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11.
David Eisenbud Craig Huneke Bernd Ulrich 《Proceedings of the American Mathematical Society》2003,131(3):701-708
In this paper we show that the Rees algebra can be made into a functor on modules over a ring in a way that extends its classical definition for ideals. The Rees algebra of a module may be computed in terms of a ``maximal' map from to a free module as the image of the map induced by on symmetric algebras. We show that the analytic spread and reductions of can be determined from any embedding of into a free module, and in characteristic 0--but not in positive characteristic!--the Rees algebra itself can be computed from any such embedding.
12.
The well-known theorem about the density of the space of probability charges with the Saks property in the space of all probability charges in the pointwise topology is proved in the vector case. New features are the uniform Saks property for the family of charges and sufficient conditions for the pointwise limit of a sequence of charges to have the Saks property. 相似文献
13.
Using multiplication algebras we introduce actor crossed modules of commutative algebras and use it to generalise some aspects from commutative algebras to crossed modules of commutative algebras. This is applied to the Peiffer pairings in the Moore complex of a simplicial commutative algebra. 相似文献
14.
T. Ehrhardt 《Acta Mathematica Hungarica》2003,99(3):233-262
We give another proof of the Szeg\H{o}–Widom Limit Theorem. This proof relies on a new Banach algebra method that can be directly
applied to the asymptotic computation of the Toeplitz determinants. As a by-product, we establish an interesting identity
for operator determinants of Toeplitz operators, namely if
are certain matrix valued functions defined on the unit circle, then
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
15.
A characterization of principal congruences of the subvariety C of semi-DeMorgan algebras is given. This characterization is applied to determine the subdirectly irreducible algebras of
the variety C and to describe a poset such that the lattice of its order ideals is isomorphic to the lattice of subvarieties of C.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
We deal with iterative algebras of functions of
-valued logic lacking projections, which we call algebras without projections. It is shown that a partially ordered set of algebras of functions of
-valued logic, for
, without projections contains an interval isomorphic to the lattice of all iterative algebras of functions of
-valued logic. It is found out that every algebra without projections is contained in some maximal algebra without projections, which is the stabilizer of a semigroup of non-surjective transformations of the basic set. It is proved that the stabilizer of a semigroup of all monotone non-surjective transformations of a linearly ordered 3-element set is not a maximal algebra without projections, but the stabilizer of a semigroup of all transformations preserving an arbitrary non one-element subset of the basic set is. 相似文献
17.
We study the system of nonlinear differential equations which expresses the constancy of the algebraic invariants of the Jacobian matrix for smooth vector fields in three-dimensional space. This system is equivalent to the equations of gas dynamics which describe the barochronous motions of a gas (the pressure and density depend only on the time). We present the results of computation of the admissible local Lie group and construction of the general solution of the system. We mention a few new problems that arise here. 相似文献
18.
Mathematical Notes - 相似文献
19.
SomeResultsConcerningHereditaryAlgebras¥LuYeguang(Hefeiof,InstituteofEconomyandTechnology)Abstract:Inthispeper,theAlprin'scou... 相似文献
20.
For a finite dimensional semisimple Lie algebra
and a root q of unity in a field k, we associate to these data a double quiver
. It is shown that a restricted version of the quantized enveloping algebras
is a quotient of the double quiver algebra
.*The author is partially supported by the National Science Foundation of China (Grant. 10271014) and Natural Science Foundation of Beijing City (grant. 1042001) 相似文献