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We have investigated spherically symmetric spacetimes which contain a perfectfluid obeying the polytropic equation of state and admit a kinematicself-similar vector of the second kind which is neither parallel nor orthogonalto the fluid flow. We have assumed two kinds of polytropic equations of stateand shown in general relativity that such spacetimes must be vacuum.Comment: 5 pages, no figures. Revtex. One word added to the title. Final  version to appear in Physical Review D as a Brief Repor

No go theorem for kinematic self-similarity with a polytropic equation of state