If light has no mass and gravity only affects objects with mass, why is light deflected by a black hole?

 Great question! This is where Einstein's General Theory of Relativity comes in.

You're right that light has no mass, so if we only considered Newtonian gravity (which applies force to masses), light shouldn't be affected by gravity. However, Einstein showed that gravity isn't just a force between masses—it's actually the bending of spacetime itself.

How Light Bends Near a Black Hole:

1. Gravity Warps Spacetime – According to General Relativity, massive objects (like black holes) curve the fabric of spacetime around them.

2. Light Follows Curved Paths – Light always travels in the straightest possible path, but when spacetime itself is curved, those "straight" paths become curved too. This is why light appears to bend around a massive object.

Why Light Can't Escape a Black Hole:

• A black hole's gravitational pull is so strong that it bends spacetime to an extreme.

• At the event horizon (the point of no return), spacetime is curved so much that all possible paths lead inward.

• Since light follows spacetime, it gets trapped inside.

This effect is called gravitational lensing, and we actually observe it with distant galaxies and black holes bending light from objects behind them. It also explains why time slows down near a black hole due to gravitational time dilation.

So, light isn’t "pulled" like a rock would be in Newtonian physics—it simply follows the curved spacetime created by gravity! 🚀