Photons: a Definition

[Mirinee]

Darkness is the absence of light, and 'light' here means the frequencies of the EM waves human eyes can see. I forgot to add that EM waves only travel at the speed of light in a vacuum.

Dark matter would be this, similar to a photon, something with mass, no charge and it doesn't interact with the surrounding environment. That is of course unless you count the gravitational effects you see from it.

Don't know about Dark Matter, but I know it's not similar to a photon, because photons have no mass.

I took Physics at school too (British A-level), and I even did the module on Nuclear and Particle physics, but it didn't go very deep. Think you have to do it at university level to get at all the "interesting" stuff. I like Newtonian physics much better than quantum physics! Too bad it doesn't help us explain about photons. Boo.