Asymptotic decomposition of a smooth measure in a Hilbert space (Q5960271)

For real separable Hilbert space \((H,\|.\|,(.,.))\) the author constructs an analogue of izoperimetric estimate of the type \( V(A+tB) = V(A)+ tS(A) +o(t) \) [\textit{H. Hadwiger}, ``Notes about volume, surface area and isoperimetric'', Nauka, Moscow (1966; Zbl 0145.19104)]. Besides, a surface measure is considered in general case which was constructed in [\textit{O.~D.~Dyachkin}, Mosc. Univ. Math. Bull. 42, No.~2, 27-29 (1987; Zbl 0656.28010)].