If light has no mass, how does gravitational force bend light inwards

Question

In the case of black holes, lights are pulled into by great gravitational force exerted by the dying stars (which forms into a black hole). If light has no mass, how is light affected by gravity?

In: 784

Answer 1

You can kind of think of mass as “at rest” since speed affects mass. Light has no “at rest” so the concept of mass doesn’t really even make sense.

Light does have momentum though, which is classically mass times velocity which implies mass can’t be zero. But Einstein made it all weird (ie. more correct) with relativity, so it’s mostly two not quite compatible systems conflicting in our heads.