Hi Chris,
As with most questions we get about light and mass, the confusion arises because there are two definitions of the word "mass," and they are often confused.
Nothing with rest mass can go at the speed of light. Light has no rest mass, but it does have what we call relativistic mass, which arises from both rest mass and kinetic energy.
If you think you found a mass-based paradox by asking a simple question, you probably mixed up your definitions of mass.
Cheers,
David
(published on 04/22/2014)
