Please Register or Log in to view the hidden image! It's a case of extent and size. I'm sure its been told to you in the many conversations on this forum re the confirmation of GW's and BH's that they are difficult to detect and probably impossible to detect from the Earth.......Although GP-B did verify and validate the Lense Thirring effect. They are real though. Let me give you an example..... Light and photons have no known rest mass...but they do have momentum, that has its effects as demonstrated with solar sails: And also light itself, due to that momentum, will warp/curve the spacetime in its vicinity, but by a teensy weensy amount......An amount we will probably never be able to measure....but just as real.