On the symmetric average of a convex body

نویسندگان

  • O. Guédon
  • A. E. Litvak
چکیده

We introduce a new parameter, symmetric average, which measures the asymmetry of a given non-degenerated convex body K in Rn. Namely, sav(K) = infa∈intK ∫ Ka ‖ − x‖Ka dx/|K|, where |K| denotes the volume of K and Ka = K − a. We show that for polytopes sav(K) ≤ C ln N , where N is the number of facets of K. Moreover, in general n n+1 ≤ sav(K) < √ n and equality in the lower bound holds if and only if K is centrally symmetric. We apply these estimates to provide bounds for covering K by homotets of K ∩ −K.

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تاریخ انتشار 2009