Why are stars capable of bending light with their gravity when light itself supposedly has no mass???

Question

Thanks

Answer 1

Think of it this way: Light travels from point A to B following the shortest possible route (in the normal world this would be a straight line). Einstein's general relativity predicts that stars, which are concentrated masses, distort / bend space such that the shortest possible trajectory is no longer a straight line as viewed from the outside.

We know that, from Newtonian mechanics, force of gravity can bend the trajectories of objects with mass (but since light is massless, it is not bent). Another way (more general) to formulate gravity is not as a force, but as a curvature in space. In this case, light is indeed affected by the curvature even though it is massless.

Answer 2

Good question:

If Gravity only affects objects with mass, why does it affect a photon?

Well, it turns out simply, in general relativity predicted by Einstein, gravity is not a force, but a dint created by objects with mass on the "space-time fabric."

So imagine taking a blanket in the air, and stretching it out until it is semi-tense. Then put a bowling ball on the blanket. What does it do? The blanket sags down. Even though light does not have mass, it travels on a particular path. And if the path is bent, then light will have to follow it around. Therefore, massive objects , like earth bend light. So do small objects, but very minimally.

Answer 3

Light has zero REST mass, but it is never really at rest. The way to think of it in terms of general relativity is that light travels in straight lines along a 3-dimensional space-time grid. However, according to general relativity, a large mass (actually any mass) will warp or curve space-time, so a light beam travailing near a large mass follows the curved space-time near the mass and is bent.

Answer 4

The star's mass warps the space around it.

The light is traveling in a straight line, but through curved space.

Light does have a little mass. Depending on how you define mass of course. Not enough to be relevant to traveling near anything but a super-massive black hole though

Answer 5

The stars don't bend light directly.

They bend the space around them. Light traveling through that space follows the bent space, so it looks like the light itself is bending.

Answer 6

you could think of of area as a versatile, malleable "fabric." something with an excellent number of mass, like a celebrity, will reason area to bend, warp, and at times, as with black holes, be torn. that is this curvature of area that promises us gravity. besides, consistent with how a lot mass an merchandise has, the extra it curves area. Now, easy follows a straight away direction until there is something curving the gap in its direction, wherein case that is going to that is going to persist with that curvature. image a bare mattress. in case you place a baseball interior the middle of the mattress and not the rest, that is going to stay interior the middle. yet, in case you have been to stand on the middle of the mattress and found the baseball some inches faraway from you, the baseball will inevitably roll in the direction of you. Your weight has curved the exterior of the mattress inflicting in spite of's next to you to roll to the place you're status.

Answer 7

As you know, gravity is actually a curvature of space brought on by the presence of mass, such as stars, planets, people, etc.,. Everything in the universe is embedded in space, including light, and must follow the geometery (..shape..) of space.

Answer 8

This is from Einstein's theory of relativity? yea? Is it stars' gravity that bends the light? I'm not sure but I thought it was the magnatism. Electro-magnatism. Or maybe that's the same thing by another name.

If light, electricity and energy 'are but different manifestations of the same thing', and they are [just as Einstein tells us] then anything can be so.

Answer 9

i'm going against popular opinion--& say that light does have mass--aka solar wind--if the sun is LIGHT-& the SUN contains 99.85 of all the matter in the solar system--then why does not light have mass--light has mass--we just can't put a number on it--this goes beyond E=mc2 general or special relativity--i'm working on this i'll get back to you

Answer 10

light has no mass....but it is made of particles which flows in wavelenght....and so the flow of it can be changed....like in the example of gravity bending the light.
that light is made of particles is proved by quantum mechanics and several experiments were conducted to verify the same.