# Does bending the direction of light generate space curvature?

When light passes a mass, the light path is bent due to the curvature of space caused by the object mass. Is there an inverse effect of bending a light path to cause an effect of generating a level of space curvature?

• The direction of causality is an interesting question, because the equations only declare relations, without saying anything, what causes what. – peterh Oct 10 '18 at 23:32
• What are the related equations in this instance? Appreciate your input. – willija5 Oct 15 '18 at 11:41

## 1 Answer

The answer is no. The metric generates the geodesic of the ray, not the other way around. The black hole would still bend spacetime even if there was no ray. The photon does bend spacetime though, but not enough to change the metric significantly.

• Please expand on photons bending spacetime. What are the related equations. Appreciate your input. – willija5 Oct 15 '18 at 11:44
• Photons also have energy and therefore a mass equivalent, that's why a box full of photons weights more than an empty box, the total energy is the frequency observed at infintiy times the planck constant plus the negative potential energy: E=hf√(1-rs/r) – Yukterez Oct 15 '18 at 15:42