Almost euclidean sections in spaces with a symmetric basis

Author(s):  
J. Bourgain ◽  
J. Lindenstrauss
Keyword(s):  

1999 ◽  
Vol 1999 (511) ◽  
pp. 1-42 ◽  
Author(s):  
Hermann König ◽  
Carsten Schütt ◽  
Nicole Tomczak-Jaegermann

Abstract The projection constants of the lpn-spaces for 1 ≦ p ≦ 2 satisfy with in the real case and in the complex case. Further, there is c < 1 such that the projection constant of any n-dimensional space Xn with 1-symmetric basis can be estimated by . The proofs of the results are based on averaging techniques over permutations and a variant of Khintchine's inequality which states that



2008 ◽  
Vol 77 (3) ◽  
pp. 396-397 ◽  
Author(s):  
A. I. Novikova ◽  
E. M. Semenov ◽  
F. A. Sukochev
Keyword(s):  


1992 ◽  
Vol 34 (3) ◽  
pp. 271-276
Author(s):  
J. Zhu

The question “Does a Banach space with a symmetric basis and weak cotype 2 (or Orlicz) property have cotype 2?” is being seriously considered but is still open though the similar question for the r.i. function space on [0, 1] has an affirmative answer. (If X is a r.i. function space on [0, 1] and has weak cotype 2 (or Orlicz) property then it must have cotype 2.) In this note we prove that for Lorentz sequence spaces d(a, 1) they both hold.



Positivity ◽  
2013 ◽  
Vol 18 (1) ◽  
pp. 147-159
Author(s):  
P. N. Dowling ◽  
D. Freeman ◽  
C. J. Lennard ◽  
E. Odell ◽  
B. Randrianantoanina ◽  
...  




2014 ◽  
Vol 2014 ◽  
pp. 1-17 ◽  
Author(s):  
Xuli Han

A symmetric basis of trigonometric polynomial space is presented. Based on the basis, symmetric trigonometric polynomial approximants like Bernstein polynomials are constructed. Two kinds of nodes are given to show that the trigonometric polynomial sequence is uniformly convergent. The convergence of the derivative of the trigonometric polynomials is shown. Trigonometric quasi-interpolants of reproducing one degree of trigonometric polynomials are constructed. Some interesting properties of the trigonometric polynomials are given.



2003 ◽  
Vol 157 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Peter G. Casazza ◽  
Niels J. Nielsen
Keyword(s):  


1980 ◽  
Vol 32 (6) ◽  
pp. 1382-1389 ◽  
Author(s):  
P. G. Casazza ◽  
Bor-Luh Lin ◽  
R. H. Lohman

The first infinite-dimensional reflexive Banach space X such that no subspace of X is isomorphic to c0 or lp, 1 ≦ p < ∞, was constructed by Tsirelson [8]. In fact, he showed that there exists a Banach space with an unconditional basis which contains no subsymmetric basic sequence and which contains no superreflexive subspace. Subsequently, Figiel and Johnson [4] gave an analytical description of the conjugate space T of Tsirelson's example and showed that there exists a reflexive Banach space with a symmetric basis which contains no superreflexive subspace; a uniformly convex space with a symmetric basis which contains no isomorphic copy of lp, 1 < p < ∞; and a uniformly convex space which contains no subsymmetric basic sequence and hence contains no isomorphic copy of lp, 1 < p < ∞. Recently, Altshuler [2] showed that there is a reflexive Banach space with a symmetric basis which has a unique symmetric basic sequence up to equivalence and which contains no isomorphic copy of lp, 1 < p < ∞.



2008 ◽  
Vol 348 (1) ◽  
pp. 51-54 ◽  
Author(s):  
F. Albiac ◽  
C. Leránoz


Sign in / Sign up

Export Citation Format

Share Document