Science in China Series A: Mathematics

, Volume 42, Issue 5, pp 478–487 | Cite as

Some relations between entropy and approximation numbers

  • Zhiming Zheng


A general result is obtained which relates the entropy numbers of compact maps on Hilbert space to its approximation numbers. Compared with previous works in this area, it is particularly convenient for dealing with the cases where the approximation numbers decay rapidly. A nice estimation between entropy and approximation numbers for noncompact maps is given.


compact and noncompact linear maps entropy numbers approximation numbers 


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Copyright information

© Science in China Press 1999

Authors and Affiliations

  • Zhiming Zheng
    • 1
  1. 1.School of Mathematical SciencesPeking UniversityBeijingChina

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