I recently engaged in a argument with a fellow that tried telling me that gravitational lensing was not because of the warping of space due to mass but instead he told me this " On a cosmic scale , the mowing energy is in the form of angular momentum, quantum mechanically , the creation of rotation-counter rotation is easy to see and understand. The light bending or space bending theories cannot get things spinning and happily ignore 99% of the entire cosmic moving energy. in the case of the existing counter rotating galaxies the nonlocal quantum mechanical momentum creation explains it just fine" Now am I just being ignorant or does this statement make no sense what so ever when it comes to gravitational lensing? "He said that a prism bends light and in such case the photons interact directly with the medium that is the glass that's space bending isn't it" Someone please tell me what he is trying to say lol I tried every argument and source I could use to try and show him that light needs a media to travel through and in space there are no glasses so what is the light propagating through to bend it??