Geometry of the Banach spaces C(βℕ × K,X) for compact metric spaces K

Dale E. Alspach; Elói Medina Galego

Studia Mathematica (2011)

  • Volume: 207, Issue: 2, page 153-180
  • ISSN: 0039-3223

Abstract

top
A classical result of Cembranos and Freniche states that the C(K,X) space contains a complemented copy of c₀ whenever K is an infinite compact Hausdorff space and X is an infinite-dimensional Banach space. This paper takes this result as a starting point and begins a study of conditions under which the spaces C(α), α < ω₁, are quotients of or complemented in C(K,X). In contrast to the c₀ result, we prove that if C(βℕ ×[1,ω],X) contains a complemented copy of C ( ω ω ) then X contains a copy of c₀. Moreover, we show that C ( ω ω ) is not even a quotient of C ( β × [ 1 , ω ] , p ) , 1 < p < ∞. We then completely determine the separable C(K) spaces which are isomorphic to a complemented subspace or a quotient of a C ( β × [ 1 , α ] , p ) space for countable ordinals α and 1 ≤ p < ∞. As a consequence, we obtain the isomorphic classification of the C ( β × K , p ) spaces for infinite compact metric spaces K and 1 ≤ p < ∞. Indeed, we establish the following more general cancellation law. Suppose that the Banach space X contains no copy of c₀ and K₁ and K₂ are infinite compact metric spaces, then the following statements are equivalent: (1) C(βℕ ×K₁,X) is isomorphic to C(βℕ ×K₂,X). (2) C(K₁) is isomorphic to C(K₂). These results are applied to the isomorphic classification of some spaces of compact operators.

How to cite

top

Dale E. Alspach, and Elói Medina Galego. "Geometry of the Banach spaces C(βℕ × K,X) for compact metric spaces K." Studia Mathematica 207.2 (2011): 153-180. <http://eudml.org/doc/285479>.

@article{DaleE2011,
abstract = {A classical result of Cembranos and Freniche states that the C(K,X) space contains a complemented copy of c₀ whenever K is an infinite compact Hausdorff space and X is an infinite-dimensional Banach space. This paper takes this result as a starting point and begins a study of conditions under which the spaces C(α), α < ω₁, are quotients of or complemented in C(K,X). In contrast to the c₀ result, we prove that if C(βℕ ×[1,ω],X) contains a complemented copy of $C(ω^\{ω\})$ then X contains a copy of c₀. Moreover, we show that $C(ω^\{ω\})$ is not even a quotient of $C(βℕ ×[1,ω],ℓ_\{p\})$, 1 < p < ∞. We then completely determine the separable C(K) spaces which are isomorphic to a complemented subspace or a quotient of a $C(βℕ ×[1,α],ℓ_\{p\})$ space for countable ordinals α and 1 ≤ p < ∞. As a consequence, we obtain the isomorphic classification of the $C(βℕ ×K,ℓ_\{p\})$ spaces for infinite compact metric spaces K and 1 ≤ p < ∞. Indeed, we establish the following more general cancellation law. Suppose that the Banach space X contains no copy of c₀ and K₁ and K₂ are infinite compact metric spaces, then the following statements are equivalent: (1) C(βℕ ×K₁,X) is isomorphic to C(βℕ ×K₂,X). (2) C(K₁) is isomorphic to C(K₂). These results are applied to the isomorphic classification of some spaces of compact operators.},
author = {Dale E. Alspach, Elói Medina Galego},
journal = {Studia Mathematica},
keywords = {isomorphisms of spaces; Stone-Čech compactification; compact metric spaces},
language = {eng},
number = {2},
pages = {153-180},
title = {Geometry of the Banach spaces C(βℕ × K,X) for compact metric spaces K},
url = {http://eudml.org/doc/285479},
volume = {207},
year = {2011},
}

TY - JOUR
AU - Dale E. Alspach
AU - Elói Medina Galego
TI - Geometry of the Banach spaces C(βℕ × K,X) for compact metric spaces K
JO - Studia Mathematica
PY - 2011
VL - 207
IS - 2
SP - 153
EP - 180
AB - A classical result of Cembranos and Freniche states that the C(K,X) space contains a complemented copy of c₀ whenever K is an infinite compact Hausdorff space and X is an infinite-dimensional Banach space. This paper takes this result as a starting point and begins a study of conditions under which the spaces C(α), α < ω₁, are quotients of or complemented in C(K,X). In contrast to the c₀ result, we prove that if C(βℕ ×[1,ω],X) contains a complemented copy of $C(ω^{ω})$ then X contains a copy of c₀. Moreover, we show that $C(ω^{ω})$ is not even a quotient of $C(βℕ ×[1,ω],ℓ_{p})$, 1 < p < ∞. We then completely determine the separable C(K) spaces which are isomorphic to a complemented subspace or a quotient of a $C(βℕ ×[1,α],ℓ_{p})$ space for countable ordinals α and 1 ≤ p < ∞. As a consequence, we obtain the isomorphic classification of the $C(βℕ ×K,ℓ_{p})$ spaces for infinite compact metric spaces K and 1 ≤ p < ∞. Indeed, we establish the following more general cancellation law. Suppose that the Banach space X contains no copy of c₀ and K₁ and K₂ are infinite compact metric spaces, then the following statements are equivalent: (1) C(βℕ ×K₁,X) is isomorphic to C(βℕ ×K₂,X). (2) C(K₁) is isomorphic to C(K₂). These results are applied to the isomorphic classification of some spaces of compact operators.
LA - eng
KW - isomorphisms of spaces; Stone-Čech compactification; compact metric spaces
UR - http://eudml.org/doc/285479
ER -

NotesEmbed ?

top

You must be logged in to post comments.

To embed these notes on your page include the following JavaScript code on your page where you want the notes to appear.

Only the controls for the widget will be shown in your chosen language. Notes will be shown in their authored language.

Tells the widget how many notes to show per page. You can cycle through additional notes using the next and previous controls.

    
                

Note: Best practice suggests putting the JavaScript code just before the closing </body> tag.