&gt;(1) We should see this as some inconsistency in how gravity scales with the mass of a black hole. The larger ones would have proportionately greater &#x27;drag&#x27; on leaving gravitrons.<p>Perhaps, no clue how a quantum mechanical gravity would interact with a black hole.<p>&gt;(2) If they are massive, and therefore subject to slowing, shouldn&#x27;t gravity waves leaving a black hole be subject to some sort of doppler effect? Should we be looking for red&#x2F;blueshifts in these waves?<p>The Doppler effect happens even for light, which isn&#x27;t massive at all (that we know of).<p>&gt;(3) If gravitrons have mass and are subject to gravity, what brings that gravity? What sub-gravitron particle regulates gravity going in&#x2F;to&#x2F;out of the gravitron?<p>There&#x27;s no reason they couldn&#x27;t interact with themselves, in fact I guess that&#x27;s probably the most likely case.