Is Quantum Spacetime Foam Unstable?

Is super-Planckian physics visible? -- Scattering of black holes in 5 dimensions

Is Supernovae Data in Favour of Isotropic Cosmologies?

Is the $ISO(2,1)$ Gauge Gravity equivalent to the Metric Formulation?

Is the accelerated expansion evidence of a forthcoming change of signature on the brane?

Is the active gravitational mass of a charged body distance-dependent?

Is the brick-wall model unstable for a rotating background?

Is the cosmological "constant" a nonlocal quantum residue of discreteness of the causal set type?

Is the cosmological singularity really unavoidable in general relativity?

Is the equivalence for the response of static scalar sources in the Schwarzschild and Rindler spacetimes valid only in four dimensions?

Is the Exponential of the Chern-Simons Action a Normalizable Physical State?

Is the gravitational action additive?

Is the Lorentz signature of the metric of spacetime electromagnetic in origin?

Is the Mass Scale for Elementary Particles Classically Determined?

Is the notion of time really fundamental?

Is the physics within the Solar system really understood?

Is the pioneer anomaly a counter example to the dark matter hypothesis?

Is the principle of equivalence a principle?

Is the Regge Calculus a consistent approximation to General Relativity?

Is the Schwarzschild black hole really stable?