A general paradigm for describing classical (and semiclassical) gravity ispresented. This approach brings to the centre-stage a holographic relationshipbetween the bulk and surface terms in a general class of action functionals andprovides a deeper insight into several aspects of classical gravity which haveno explanation in the conventional approach. After highlighting a series ofunresolved issues in the conventional approach to gravity, I show that (i)principle of equivalence, (ii) general covariance and (iii)a reasonablecondition on the variation of the action functional, suggest a genericLagrangian for semiclassical gravity of the form $L=Q_a^{bcd}R^a_{bcd}$ with$\nabla_b Q_a^{bcd}=0$. The expansion of $Q_a^{bcd}$ in terms of thederivatives of the metric tensor determines the structure of the theoryuniquely. The zeroth order term gives the Einstein-Hilbert action and the firstorder correction is given by the Gauss-Bonnet action. Any such Lagrangian canbe decomposed into a surface and bulk terms which are related holographically.The equations of motion can be obtained purely from a surface term in thegravity sector. Hence the field equations are invariant under thetransformation $T_{ab} \to T_{ab} + \lambda g_{ab}$ and gravity does notrespond to the changes in the bulk vacuum energy density. The cosmologicalconstant arises as an integration constant in this approach. The implicationsare discussed.
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