TY - JOUR
T1 - On an analogue of a theorem by Astala and Tylli
AU - Karlovich, Alexei
AU - Shargorodsky, Eugene
N1 - Funding Information:
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UIDB%2F00297%2F2020/PT#
Publisher Copyright:
© 2021, Springer Nature Switzerland AG.
PY - 2022/1
Y1 - 2022/1
N2 - Let ‖ A‖ e be the essential norm of an operator A and ‖ A‖ m be the infimum of the norms of restrictions of A to the subspaces of finite codimension. We show that if ‖ A‖ e< M‖ A‖ m holds for every bounded noncompact operator A from a Banach space X to every Banach space Y, then the space X has the dual compact approximation property. This is an analogue of a result by Astala and Tylli (J Funct Anal 70(2):388–401, 1987) concerning the Hausdorff measure of noncompactness and the bounded compact approximation property.
AB - Let ‖ A‖ e be the essential norm of an operator A and ‖ A‖ m be the infimum of the norms of restrictions of A to the subspaces of finite codimension. We show that if ‖ A‖ e< M‖ A‖ m holds for every bounded noncompact operator A from a Banach space X to every Banach space Y, then the space X has the dual compact approximation property. This is an analogue of a result by Astala and Tylli (J Funct Anal 70(2):388–401, 1987) concerning the Hausdorff measure of noncompactness and the bounded compact approximation property.
KW - Bounded compact approximation property
KW - Dual compact approximation property
KW - Essential norm
KW - Measures of noncompactness
UR - http://www.scopus.com/inward/record.url?scp=85119830683&partnerID=8YFLogxK
U2 - 10.1007/s00013-021-01679-w
DO - 10.1007/s00013-021-01679-w
M3 - Article
AN - SCOPUS:85119830683
SN - 0003-889X
VL - 118
SP - 73
EP - 77
JO - Archiv der Mathematik
JF - Archiv der Mathematik
IS - 1
ER -