# why light bends in presence of gravitational field..

As light is combination of electric and magnetic field.. And it bends in presence of gravitational field.. Does it imply that, although gravational and electric or magnetic fields are different but can interact with each other.. But how and why?

Note by Kautsya Kanu
6 years, 11 months ago

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What is the physical meaning of bending of space.. Space is 3D.. Then what is exactly meaning of bending.. And why I take it as 2D sheet.. Please elaborate it..

- 6 years, 11 months ago

For easier understanding we can consider space as 2D because working with it in 3D becomes complicated :P

- 6 years, 11 months ago

First of all space is 4D and believed to be of more Ds and not just 3D...

Reason of bending is-- The presence of a massive object slows the passage of time in its neighborhood. This makes space appear to be curved since light travels slower the nearer it gets to the object.

- 6 years, 11 months ago

Time, length, mass and direction are all dimensions that occur in our universe. We can't separate them, although we try to in our use of language, and in trying to set up problems that can be solved. So, space is length and direction, and we envisage it as having straight lines. But space changes over time, so time and space need to be considered as a single entity. In this entity, mass exists in both space and time, and hence it distorts both, and space and time distort mass.

- 6 years, 11 months ago

This was bending of space. In space, distance btw 2 points is not a mere straight line, it can be shortened far more by bending of space.... (theoretically, wormholes and warpdrive are an application of bending space time)

- 6 years, 11 months ago

According to modern theory... Gravity doesn't bend light.From the perspective of light, it's always going in a perfectly straight line.But gravity shapes the space that the light passes through,so from our perspective the path is not straight.

It is similar to we walking on curved earth but we still feel we are walking on a straight line but to someone watching us from above, we are going in a round path.

- 6 years, 11 months ago

Ok then how light is captured in a black hole ?

- 6 years, 11 months ago

Black holes bend space time.Anything that can bend space time can bend light.

To visualise it

Think of space time as a "2D" sheet, then place various celestial objects with a large mass on the sheet. They will cause a slight dent in it.

Think of black hole as an object that can create such a dent whose depth is limitless...Therefore it can not only bend light but it can capture and "eat" light too.

- 6 years, 11 months ago

How are you so knowledgeable in Physics?

- 6 years, 11 months ago

I think I'm OK ok only in cosmology (physics related to space)..I aspire to become cosmologist :) Thus I find cosmology intresting Not iit jee portion.... :P

I got these knowledge from book by Stephen hawking called brief history of time and some were got from net and some shows on discovery and national geographic...I recommend it to many PPL as it is damm intresting :P

- 6 years, 11 months ago

You should also read grand design;and theory of everything both are by Stephen Hawking

- 6 years, 11 months ago

:D.Nice to know

- 6 years, 11 months ago