Gravitational Lensing, Refraction & Diffraction: Three Sides to the Same Coin?

Here, we thought we would explain the difference between the terms and how they interact with light (from both a wave and particle point of view): http://www.fromquarkstoquasars.com/gravitational-lensing-refraction-diffraction-three-sides-to-the-same-coin/

Original Image Credit: Unknown (But if you do, please let us know)