共查询到20条相似文献,搜索用时 15 毫秒
1.
D. A. Redett 《Proceedings of the American Mathematical Society》2005,133(4):1151-1156
In this note we extend the ``Beurling type' characterizations of subspaces of and to and , respectively.
2.
Michal Misiurewicz Ana Rodrigues 《Proceedings of the American Mathematical Society》2005,133(4):1109-1118
The famous problem involves applying two maps: and to positive integers. If is even, one applies , if it is odd, one applies . The conjecture states that each trajectory of the system arrives to the periodic orbit . In this paper, instead of choosing each time which map to apply, we allow ourselves more freedom and apply both and independently of . That is, we consider the action of the free semigroup with generators and on the space of positive real numbers. We prove that this action is minimal (each trajectory is dense) and that the periodic points are dense. Moreover, we give a full characterization of the group of transformations of the real line generated by and .
3.
Ian M. Aberbach 《Proceedings of the American Mathematical Society》2005,133(1):27-29
Let be an excellent local ring of positive prime characteristic. We show that if , then is regular. This improves a result of Schoutens, in which the additional hypothesis that was an isolated singularity was required for the proof.
4.
D. A. Redett 《Proceedings of the American Mathematical Society》2005,133(5):1459-1461
In this note, we give a new proof of the characterization of the -invariant subspaces of for in using ideas from approximation theory. 相似文献
5.
L. D. Abreu 《Proceedings of the American Mathematical Society》2005,133(4):1197-1203
A -version of the sampling theorem is derived using the -Hankel transform introduced by Koornwinder and Swarttouw. The sampling points are the zeros of the third Jackson -Bessel function.
6.
Damir Bakic 《Proceedings of the American Mathematical Society》2005,133(2):441-448
We prove the following generalization of the noncommutative Tietze extension theorem: if is a countably generated Hilbert -module over a -unital -algebra, then the canonical extension of a surjective morphism of Hilbert -modules to extended (multiplier) modules, , is also surjective.
7.
Suppose that is a smooth -action on a closed smooth -dimensional manifold such that all Stiefel-Whitney classes of the tangent bundle to each connected component of the fixed point set vanish in positive dimension. This paper shows that if 2^k\dim F$"> and each -dimensional part possesses the linear independence property, then bounds equivariantly, and in particular, is the best possible upper bound of if is nonbounding.
8.
Kok Seng Chua 《Proceedings of the American Mathematical Society》2005,133(3):661-670
We introduce a family of bi-dimensional theta functions which give uniformly explicit formulae for the theta series of hermitian lattices over imaginary quadratic fields constructed from codes over and , and give an interesting geometric characterization of the theta series that arise in terms of the basic strongly modular lattice . We identify some of the hermitian lattices constructed and observe an interesting pair of nonisomorphic 3/2 dimensional codes over that give rise to isomorphic hermitian lattices when constructed at the lowest level 7 but nonisomorphic lattices at higher levels. The results show that the two alphabets and are complementary and raise the natural question as to whether there are other such complementary alphabets for codes.
9.
H. H. Edwards P. Mikusinski M. D. Taylor 《Proceedings of the American Mathematical Society》2005,133(5):1505-1513
A measure, , on is said to be -invariant if its value for any Borel set is invariant with respect to the symmetries of the unit square. A function, , generated in a certain way by a measure, , on is shown to be a measure of concordance if and only if the generating measure is positive, regular, -invariant, and satisfies certain inequalities. The construction examined here includes Blomqvist's beta as a special case.
10.
Themis Mitsis 《Proceedings of the American Mathematical Society》2005,133(4):1057-1061
What is the smallest for which a weight in the reverse Hölder class also belongs to the Muckenhoupt class ? We give an asymptotically sharp answer to this question.
11.
Alex N. Dranishnikov Yuli B. Rudyak 《Proceedings of the American Mathematical Society》2005,133(5):1557-1561
We construct closed -connected manifolds of dimensions that possess non-trivial rational Massey triple products. We also construct examples of manifolds such that all the cup-products of elements of vanish, while the group is generated by Massey products: such examples are useful for the theory of systols.
12.
Lizzie Burslem 《Proceedings of the American Mathematical Society》2005,133(4):1101-1108
It has been conjectured that a generic diffeomorphism on a compact manifold will have trivial centralizer. We give some partial results towards proving this conjecture within the class of area preserving diffeomorphisms of the sphere.
13.
Martha Alvarez Montserrat Corbera Joaquin Delgado Jaume Llibre 《Proceedings of the American Mathematical Society》2005,133(2):529-536
In the -body problem a central configuration is formed when the position vector of each particle with respect to the center of mass is a common scalar multiple of its acceleration vector. Lindstrom showed for and for 4$"> that if masses are located at fixed points in the plane, then there are only a finite number of ways to position the remaining th mass in such a way that they define a central configuration. Lindstrom leaves open the case . In this paper we prove the case using as variables the mutual distances between the particles.
14.
Frank Sottile Thorsten Theobald 《Proceedings of the American Mathematical Society》2005,133(10):2835-2844
Let and denote the dimension and the degree of the Grassmannian , respectively. For each there are (a priori complex) -planes in tangent to general quadratic hypersurfaces in . We show that this class of enumerative problems is fully real, i.e., for there exists a configuration of real quadrics in (affine) real space so that all the mutually tangent -flats are real.
15.
Mohammed Hichem Mortad 《Proceedings of the American Mathematical Society》2005,133(2):455-464
We give classes of unbounded real-valued for which is self-adjoint on , , where is the wave operator defined on .
16.
Hiroshi Fukushima 《Proceedings of the American Mathematical Society》2005,133(3):671-675
In this paper, we shall give examples of -groups that have Hall subgroups that are not -groups.
17.
M. M. Popov 《Proceedings of the American Mathematical Society》2005,133(7):2023-2028
Let p_1 > p_2 > \cdots > 1$">. We construct an easily determined -symmetric basic sequence in , which spans a hereditarily subspace without the Schur property. An immediate consequence is the existence of hereditarily subspaces of without the Schur property.
18.
Jerzy Kakol Stephen A. Saxon Aaron R. Todd 《Proceedings of the American Mathematical Society》2004,132(6):1703-1712
Let be a completely regular Hausdorff space, and let be the space of continuous real-valued functions on endowed with the compact-open topology. We find various equivalent conditions for to be a -space, resolving an old question of Jarchow and consolidating work by Jarchow, Mazon, McCoy and Todd. Included are analytic characterizations of pseudocompactness and an example that shows that, for , Grothendieck's -spaces do not coincide with Jarchow's -spaces. Any such example necessarily answers a thirty-year-old question on weak barrelledness properties for , our original motivation.
19.
Siu-Hung Ng 《Proceedings of the American Mathematical Society》2005,133(8):2237-2242
Let be a finite-dimensional Hopf algebra over an algebraically closed field of characteristic 0. If is not semisimple and for some odd integer , then or is not unimodular. Using this result, we prove that if for some odd prime , then is semisimple. This completes the classification of Hopf algebras of dimension .
20.
Roberto Johnson José Pantoja 《Proceedings of the American Mathematical Society》2007,135(2):579-586
Let be a non-archimedean local field with odd residual characteristic. Let be the group We construct explicit Whittaker models for any supercuspidal representation of with positive level.