Merging matter and geometry in the same Lagrangian

We show that a Lagrangian density proportional to root-gL(m)(2)/R reduces to a pressuron theory of gravity that is indistinguishable from General Relativity in the dust limit. The combination of matter and geometry in the same Lagrangian density intrinsically satisfies Mach's Principle - since matter cannot exist without curvature and vice versa - while it may have the correct phenomenology in order to describe actual gravity. (C) 2015 The Authors. Published by Elsevier B.V.