Quantum Schwarzschild geometry in effective-field-theory models of gravity

The Schwarzschild geometry is investigated within the context of effective-field-theory models of gravity. Starting from its harmonic-coordinate expression, we derive the metric in standard coordinates by keeping the leading one-loop quantum contributions in their most general form. We examine the metric horizons and the nature of the hypersurfaces having constant radius; furthermore, a possible energy-extraction process which violates the null energy condition is described, and both timelike and null geodesics are studied. Our analysis shows that there is no choice of the sign of the constant parameter embodying the quantum correction to the metric which leaves all the features of the classical Schwarzschild solution almost unaffected.