Some of the evidence for "dark matter" involves the excessive force holding stars further out on the spiral arms of a galaxy, so that they can revolve faster about the center. We know that there is a supermassive black hole consisting of 4.1-4.5 million solar masses at the center of the Milky Way: https://en.wikipedia.org/wiki/Milky_Way Our Sun is roughly in the plane of the Milky Way, and "sees" forces from every bit of mass in the Milky Way. I claim that our Sun "sees" larger-than-expected forces from masses approx 180 degrees around the Milky Way due to *gravitational lensing*. This gravitational lensing will affect the light received from the points directly opposite, but due to the masking effect of the center of the galaxy, the lensing effect on light is smaller than the lensing effect on gravity, because there is no masking effect on the gravity force from the opposite side of the galaxy. This gravitational lensing effect also operates out of the plane of the galaxy, so points 180 degrees opposite the Sun are *focused* on the Sun. One could presumably compute a "point spread function" (PSF) of this gravitational lens in a manner similar to the PSF of any other lens. This "cross-galaxy" PSF will depend upon the radius from the center of the galaxy, so there are almost certainly values of the radius for which this PSF is especially well focused. I don't know enough about GR to actually calculate this PSF, but I would imagine that this calculation isn't particularly difficult to do analytically, but even if it requires numerical simulation, it still shouldn't be a particularly challenging calculation. I'd love to know if this gravitational lensing effect is very strong compared with the usual centripetal forces on the Sun. In particular, what % addition speed does this lensing effect add to the speed of the Sun around the center of the Milky Way?