DOI: 10.68381/jca05-10 ISSN: 0944-6532

On Some Quasiconvex Functions with Linear Growth

Kewei Zhang

We establish (i) that the quasiconvexification of the distance function to any closed (possibly unbounded) subset of the space of conformal matrices

E_\partial E ∂
in M²×² is bounded from below by the distance function itself, that is, Q dist(·, K) ≥ c dist(·, K), where c > 0 is a constant independent of K; (ii) some estimates of quasiconvexifications of the distance function to a closed subset of M²×² which is ‘supported’ by
E_\partial E ∂
; (iii) Q distᵖ(·, K) = Q distᵖ(·, Qₚ(K)) for any p ≥ 1 and any closed K ⊂ Mᴺ×ⁿ; (iv) for some nonconvex K ⊂ M²×², Q dist(·, K) is homogeneous of degree one, conjugate invariant and convex, and Q₁(K) = C(K).