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51.
Using analytic methods of finite-gap integration, we construct quasihomogeneous algebraic solutions of the WDVV associativity
equations and the nonsemisimple Frobenius manifolds associated with them.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 2, pp. 195–206, May, 2007. 相似文献
52.
Damjana Kokol Bukovšek 《Linear algebra and its applications》2007,420(1):34-50
We study non-degenerate irreducible homomorphisms from the multiplicative semigroup of all n-by-n matrices over an algebraically closed field of characteristic zero to the semigroup of m-by-m matrices over the same field. We prove that every non-degenerate homomorphism from the multiplicative semigroup of all n-by-n matrices to the semigroup of (n + 1)-by-(n + 1) matrices when n ? 3 is reducible and that every non-degenerate homomorphism from the multiplicative semigroup of all 3-by-3 matrices to the semigroup of 5-by-5 matrices is reducible. 相似文献
53.
O. I. Mokhov 《Theoretical and Mathematical Physics》2007,152(2):1183-1190
We prove that the associativity equations of two-dimensional topological quantum field theories are very natural reductions
of the fundamental nonlinear equations of the theory of submanifolds in pseudo-Euclidean spaces and give a natural class of
flat torsionless potential submanifolds. We show that all flat torsionless potential submanifolds in pseudo-Euclidean spaces bear natural structures
of Frobenius algebras on their tangent spaces. These Frobenius structures are generated by the corresponding flat first fundamental
form and the set of the second fundamental forms of the submanifolds (in fact, the structural constants are given by the set
of the Weingarten operators of the submanifolds). We prove that each N-dimensional Frobenius manifold can be locally represented
as a flat torsionless potential submanifold in a 2N-dimensional pseudo-Euclidean space. By our construction, this submanifold
is uniquely determined up to motions. Moreover, we consider a nonlinear system that is a natural generalization of the associativity
equations, namely, the system describing all flat torsionless submanifolds in pseudo-Euclidean spaces, and prove that this
system is integrable by the inverse scattering method.
To the memory of my wonderful mother Maya Nikolayevna Mokhova (4 May 1926–12 September 2006)
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 2, pp. 368–376, August, 2007. 相似文献
54.
V. S. Monakhov 《Mathematical Notes》1997,61(5):585-589
Finite groups with 2-nilpotent subgroups of even index are described.
Translated fromMatematicheskie Zametki, Vol. 61, No. 5, pp. 700–705, May, 1997.
Translated by A. I. Shtern 相似文献
55.
幂格的同态与同余关系 总被引:1,自引:1,他引:0
本文在文[1]已引入幂格同态概念的基础上,进一步引入幂格同余关系的概念,并得到它们的一些相关性质.以及幂格同态与幂格同余关系的对应关系. 相似文献
56.
S. S. Kutateladze 《Siberian Mathematical Journal》2005,46(3):489-493
The modulus of an order bounded functional on a Riesz space is the sum of a pair of Riesz homomorphisms if and only if the kernel of this functional is a Grothendieck subspace of the ambient Riesz space. An operator version of this fact is given.Original Russian Text Copyright © 2005 Kutateladze S. S.__________Translated from Sibirskii Matematicheskii Zhurnal, Vol. 46, No. 3, pp. 620–624, May–June, 2005. 相似文献
57.
Max Forester 《Geometriae Dedicata》2006,121(1):43-59
We study the structure of generalized Baumslag–Solitar groups from the point of view of their (usually non-unique) splittings
as fundamental groups of graphs of infinite cyclic groups. We find and characterize certain decompositions of smallest complexity
(fully reduced decompositions) and give a simplified proof of the existence of deformations. We also prove a finiteness theorem and solve
the isomorphism problem for generalized Baumslag–Solitar groups with no non-trivial integral moduli.
相似文献
58.
We offer an almost self-contained development of Perron–Frobenius type results for the numerical range of an (irreducible) nonnegative matrix, rederiving and completing the previous work of Issos, Nylen and Tam, and Tam and Yang on this topic. We solve the open problem of characterizing nonnegative matrices whose numerical ranges are regular convex polygons with center at the origin. Some related results are obtained and some open problems are also posed. 相似文献
59.
In this paper, we present a new class of strongly singular maximal abelian subalgebras living inside the -folded tensor product of the free group factor with itself (). The notions of strongly singular masas in type factors and that of asymptotic homomorphism were introduced by A. Sinclair and R. Smith. One of their first examples was the Laplacian subalgebra of the free group factor, generated by the sum of words of length 1 in . This subalgebra was known to be a singular masa. Using the results of A. Sinclair and R. Smith, we show that the unique trace-preserving conditional expectation onto the Laplacian subalgebra of is an asymptotic homomorphism, and hence the Laplacian subalgebra is a strongly singular masa for every .
60.
Rodney Y. Sharp 《Proceedings of the American Mathematical Society》2007,135(3):665-670
Let be a commutative Noetherian local ring of prime characteristic. The purpose of this paper is to provide a short proof of G. Lyubeznik's extension of a result of R. Hartshorne and R. Speiser about a module over the skew polynomial ring (associated to and the Frobenius homomorphism , in the indeterminate ) that is both -torsion and Artinian over .