Does Light Have Weight? Exploring the Curvature of Light Around the Sun

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In summary, when we look at a star behind the sun we see that the star's light curves around the sun because the star has more gravitational mass than the Earth.
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myswhatevr
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Ok, I know this topic has been discussed before..

I just recently found out that we can see the light from a star that is BEHIND the sun (from where the Earth stands) because the light of the star is repeling the Earth's gravity which causes the light tocurve around the sun which is why we can see it...
 
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  • #3
myswhatevr said:
Ok, I know this topic has been discussed before..

I just recently found out that we can see the light from a star that is BEHIND the sun (from where the Earth stands) because the light of the star is repeling the Earth's gravity which causes the light tocurve around the sun which is why we can see it...
Yes. Light has both inertial mass (since light carries momentum) , active gravitational mass (since light can generate a gravitational field and passive gravitational mass (since light is affected by a gravitational field.

Feynman discusses this in his lectures, i.e. he explains that since light has energy and energy gas mass that light is affected by gravity. I.e. From "The Feynman Lectures on Physics," Vol -I page 7-11 - Section entitled Gravitation and Relativity
One feature of this new law is quite easy to understand is this: In Einstein relativity theory, anything which has energy has mass -- mass in the sense that it is attracted gravitationaly. Even light, which has energy, has a "mass". When a light beam, which has energy in it, comes past the sun there is attraction on it by the sun.
See also
https://www.physicsforums.com/showpost.php?p=65079&postcount=1

Pete
 
  • #4
myswhatevr said:
I just recently found out that we can see the light from a star that is BEHIND the sun
It is very confusing to use words like "behind" in curved spacetimes.
 
  • #5
Yes … some observers' behinds are more curved than others. :smile:
 

1. Does light have mass?

No, light does not have mass. Mass is defined as the amount of matter an object contains and light is made up of massless particles called photons. Therefore, it has no mass.

2. Does light have weight?

No, light does not have weight. Weight is the measure of the force of gravity on an object and since light has no mass, it cannot be affected by gravity and therefore has no weight.

3. If light has no mass, then how does it have momentum?

While light does not have mass, it does have energy and momentum. This is due to the fact that light travels at the speed of light, which is a fundamental constant in the universe. Therefore, light has momentum, but it is not due to its mass.

4. Can light be affected by gravity?

Yes, light can be affected by gravity. While it has no mass, it does have energy and momentum, which can be affected by the curvature of spacetime caused by massive objects.

5. Is light affected by the Higgs field?

No, light is not affected by the Higgs field. The Higgs field gives particles their mass, but since light has no mass, it is not affected by this field.

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