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951.
Robert Scheiber 《Advances in Applied Clifford Algebras》1999,9(2):287-308
A real representation of Dirac algebra, using η=diag(−1,1,1,1) as standard metric is discussed. Among other interesting properties
it allows to define a generalization of Lorentz transformations. Ordinary boosts and rotations are subsets The additional
transformations are shown to describe transformations to displaced systems, rotating systems, “charged systems”, and others.
Poincaré transformations are shown to be approximations of these generalized Lorentz transformations. Appendix D gives an
interpretation.
Ubi materia, ibi geometria (Johannes Kepler) 相似文献
952.
Camil I. Aponte Román 《代数通讯》2017,45(4):1793-1807
We define graded group schemes and graded group varieties and develop their theory. Graded group schemes are the graded analogue of a?ne group schemes and are in correspondence with graded Hopf algebras. Graded group varieties take the place of infinitesimal group schemes. We generalize the result that connected graded bialgebras are graded Hopf algebra to our setting and we describe the algebra structure of graded group varieties. We relate these new objects to the classical ones providing a new and broader framework for the study of graded Hopf algebras and a?ne group schemes. 相似文献
953.
引入了弱d-Koszul模,它是d-Koszul模的一种自然推广.设A是d-Koszul代数,M是有限生成的分次A-模,则M是弱d-Koszul模当且仅当M具有子模滤:0(?)U0(?)U1(?)…(?)Up=M,使得所有的A-模Ui/Ui-1是d-Koszul模.设M为一个弱d-Koszul模,则作为分次ExtA*(A0,A0)-模,其Koszul对偶:ε(M)=ExtA*(M,A0)是由0次生成的. 相似文献
954.
《Mathematische Nachrichten》2017,290(13):1991-2008
We define and characterize spaces of manifold‐valued generalized functions and generalized vector bundle homomorphisms in the setting of the full diffeomorphism‐invariant vector‐valued Colombeau algebra. Furthermore, we establish point value characterizations for these spaces. 相似文献
955.
In Huru and Lychagin (2013), it is conjectured that the quantizations of splitting fields of products of quadratic polynomials, which are obtained by deforming the multiplication, are Clifford type algebras. In this paper, we prove this conjecture. 相似文献
956.
For a continuous field of C?-algebras A, we give a criterion to ensure that the stable rank of A is one. In the particular case of a trivial field this leads to a characterization of stable rank one, completing accomplishments by Nagisa, Osaka and Phillips. Further, for certain continuous fields of C?-algebras, we study when the Cuntz semigroup satisfies the Riesz interpolation property, and we also analyze the structure of its functionals. As an application, we obtain a positive answer to a conjecture posed by Blackadar and Handelman in a variety of situations. 相似文献
957.
Miroslav Novotný 《Czechoslovak Mathematical Journal》2002,52(2):415-428
A construction of all homomorphisms of a heterogeneous algebra into an algebra of the same type is presented. A relational structure is assigned to any heterogeneous algebra, and homomorphisms between these relational structures make it possible to construct homomorphisms between heterogeneous algebras. Homomorphisms of relational structures can be constructed using homomorphisms of algebras that are described in [11]. 相似文献
958.
Wu Liangsen 《数学年刊B辑(英文版)》1994,15(2):153-156
WHENCANTHESTABLEALGEBRADETERMINETHESTRUCTUREOFAC-ALGEBRA?¥WULIANGSENAbstract:LetAandBbeC-algebras.SupposethatKisthealgebraofa... 相似文献
959.
Mehdi Sangani Monfared 《Journal of Functional Analysis》2003,198(2):413-444
It is shown that for amenable groups, all finite-dimensional extensions of Ap(G) algebras split strongly. Furthermore, each extension of Ap(G) which splits algebraically also splits strongly. We also show that if G is an almost connected locally compact group, or a subgroup of GLn(V) (V being a finite-dimensional vector space), and if for a fixed p∈(1,∞), all finite-dimensional singular extensions of Ap(G) split strongly, then G is amenable. Continuous order isomorphisms for the pointwise order of Ap(G) algebras, are characterized as weighted composition maps. Similarly, order isomorphisms for the pointwise order of Bp(G) algebras, are characterized as ∗-algebra isomorphisms followed by multiplication by an invertible positive multiplier. In addition, it is shown that for amenable groups, an order isomorphism for the pointwise order between Ap(G) algebras that preserve cozero sets is necessarily continuous, and hence induces an algebra isomorphism. 相似文献
960.
PAUL G.A. FLORIS 《Compositio Mathematica》1997,108(2):123-149
Abstract. Explicit models are constructed for irreducible *-representations of the quantised universalenveloping algebra Uq(gl(n)). The irreducible decomposition of these modules with respect to thesubalgebra Uq(gl(n-1)) is given, and the corresponding spherical and associated spherical elementsare determined in terms of little q-Jacobi polynomials. This leads to a proof of an addition theoremfor the spherical elements, the so-called q-disk polynomials. 相似文献