Dark matter does not interact with any electromagnetic radiation (this includes light) in a direct fashion, so light passes straight through dark matter. Dark matter however outweighs our regular matter by about 80% so it does produce gravitational effects. It warps space/time which light travels through as well. This warping (gravity) will bend light that is traveling in it's vicinity. This has allowed astronomers to actually map out where dark matter exists, but this is the only way that light is affected by dark matter. Other than that they completely ignore each other.
1 year ago
Last edited at 12:57PM on 2/7/2013
Light as a ray or particle couldn't really displace a material or particle, i can't think of a single case in which light displaces anything. The particles are so small in light that for example, if a gamma burst were to travel through a lightyears thickness of lead, 60 percent of the particles would make it through.