The Three Space Problem and Ideals of Operators
β Scribed by Hans Jarchow
- Publisher
- John Wiley and Sons
- Year
- 1984
- Tongue
- English
- Weight
- 553 KB
- Volume
- 119
- Category
- Article
- ISSN
- 0025-584X
No coin nor oath required. For personal study only.
β¦ Synopsis
1. Int,rodrietion
\Ve will be concerned with a particular aspect of the following quest'ion which Consider a weak CAUCHY sequence (zJ in X , and let z be its limit in [X**. o(X**, X * ) ] . If Q : X + X / Y is the quotient map, then (Qx,) converges weakly in S I P since XI1is wsc. Hence &**zEX/Y and Q**x=Qx for some X E X . Note that z -x belongs to Y**. Moreover. certain convex combinations of the Q (r -xN) form a null sequence in the BANACH space X / Y . Let A k c N be finite and Q 2 0 such that max A,<rnin A,,,, ai= 1, andjl&(z,-x)((<k-i, where z,:= ujxj, i E A ,
π SIMILAR VOLUMES
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Let X = d v p and Y = d w q be Lorentz sequence spaces. We investigate when the space K X Y of compact linear operators acting from X to Y forms or does not form an M-ideal (in the space of bounded linear operators). We show that K X Y fails to be a non-trivial M-ideal whenever p = 1 or p > q. In th