We study nonlinear approximation in the Triebel-Lizorkin spaces with dictionaries formed by dilating and translating one single function g. A general Jackson inequality is derived for best m-term approximation with su...We study nonlinear approximation in the Triebel-Lizorkin spaces with dictionaries formed by dilating and translating one single function g. A general Jackson inequality is derived for best m-term approximation with such dictionaries. In some special cases where g has a special structure, a complete characterization of the approximation spaces is derived.展开更多
In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the stru...In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the structure of these states.展开更多
基金This work is in part supported by the Danish Technical Science Foundation, Grant no. 9701481.
文摘We study nonlinear approximation in the Triebel-Lizorkin spaces with dictionaries formed by dilating and translating one single function g. A general Jackson inequality is derived for best m-term approximation with such dictionaries. In some special cases where g has a special structure, a complete characterization of the approximation spaces is derived.
文摘In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the structure of these states.
