It is known that the volume functional  ϕ↦∫e−ϕ \,\phi\mapsto\int e^{-\phi}\, satisfies certain concavity or convexity inequalities with respect to three of the four linear structures induced by the order isomorphisms acting on Cvx0(Rn){\rm{Cvx}}_0(\mathbb{R}^n). In this note we define the fourth linear structure on Cvx0(Rn){\rm{Cvx}}_0(\mathbb{R}^n) as the pullback of the standard linear structure under the J\cal J transform. We show that, interpolating with respect to this linear structure, no concavity or convexity inequalities hold, and prove that a quasi-convexity inequality is violated only by up to a factor of 22. We also establish all the order relations which the four different interpolations satisfy.

Contact details are reproduced from the original publication and may be historical.

Dan I. Florentin

Department of Mathematics, Cleveland State University, Cleveland, OH 44115-2214, U.S.A.

danflorentin@gmail.com

Alexander Segal

Afeka Academic College of Engineering, Tel Aviv 69107, Israel

segalale@gmail.com
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D. I. Florentin, A. Segal. “On the Linear Structures Induced by the Four Order Isomorphisms Acting on Cvx_0(ℝ^n).” Journal of Convex Analysis 28 (2021), No. 3, 751–760. https://doi.org/10.68381/jca28042