Does Law of Gravitation apply to Light? If not, why?

Answer 1

No, not directly.

The core of gravitation is Einstein's equation Gab = Tab, relating the metric structure of the universe locally to the gravitational mass/field.

Light travels in straight lines and, being massless, is not influenced by gravity. However, the straight lines in this metricized spacetime are not Euclidean straight lines. Light doesn't bend but the manifold geometry of spacetime does.

Gravitation only applies to light to the extent that gravitation defines the structure of spacetime light travels in. Black Holes are often cited as bending light. They do not. They are extreme operators on bending spacetime locally and thus rectilinear paths are extraordinarily curved.

Answer 2

If you are referring to the familiar Newton's law of attraction (GMm/r^2), it will be impossible to see it affecting light. After all, light has no mass, people think it is a wave etc.

Einstein viewed it differently. He said that an object with mass "curves the space" around it. People usually demonstrate it in 2 dimensions by placing a heavy ball on an elastic sheet (a sofa or bed will do too) and shooting a small ball skirting it, and pointing out how it does not travel in a straight line. It is easy to intuitively see, using this point of view, that light could bend near an object too - whether light has mass or not.

This notion, General Relativity, is more complex, and has greater predictive power than Newton's law.

Answer 3

Yes Anil gravitational law applies to light too



SInce light is of dual nature i.e of wave nature and particle nature.


it can also be proved by observing black holes in universe.
they gravitational pull is so so high that even light(photon particle) cant overcome it....

Answer 4

Yes it does, black holes in the universe even pull in light.

I remember seeing I demonstration of flying around the world with a light timer eventually you are flying so fast light bends and you start traveling through time.

This was just a science show with hypothetical theories.

Answer 5

Yes

Very dense objects, such as those at the centre of black holes, bend light passing by, through gravitational attraction.

Answer 6

Using the energy and momentum tensor one can find out how the space-time is curved. Light must follow geodiscs and will follow the "apparently" curved line and therefore is affected by gravity.

Answer 7

Yes, it does.

If it did not then energy could be created from nothing and perpetual motion would be possible.

It was this realisation that led Einstein to his famous General Theory of Relativity.

Answer 8

Gravity acts only on mass. Light is devoid of mass.

Answer 9

YES BLACK HOLES ATRRACT LIGHT