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?

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Answer 1

Gravity is not a force; mass just bends space-time. It seems a minor difference, and given how long we’ve worked successfully with the force assumption, in some sense it is. But that assumption doesn’t explain why light is clearly observed to bend around black holes — which is why we needed a new one that does.