No robust phases in aerogel: 3He-A with orientational disorder in the Ginzburg-Landau model

Abstract

In series of papers Fomin introduced and discussed the so-called robust phases in a system with frozen orientational disorder (with application to superfluid 3He in aerogel). We show that his consideration is based on the erroneous overestimation of the fluctuation energy which comes from the interaction of the Goldstone modes with the frozen disorder. This interaction leads to the Imry-Ma effect, which destroys the orientational order, but is unable to destroy the local structure of the A-phase. There is no ground for the robust phases.