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Does light obey gravity?
In our everyday experience, light seems to travel in straight lines, unaffected by gravity. But that bending is not gravitational; it’s electromagnetic. However, light does bend when travelling around massive bodies like neutron stars and black holes. This is explained by Einstein’s theory of general relativity.
Does light ignore gravity?
Short answer: no. However, when falling in a gravity field, the momentum of light increases. In Relativistic mechanics, these quantities are not proportional.
How does gravity interact with light?
Gravity attracts anything that has momentum. Light has a speed and the photons have a mass. Though the mass of a photon is very very small but still it produces significant finite value for its momentum. If the gravity is strong enough then it can pull light itself into it.
Does light need gravity?
No. Light has no physical mass. Therefore it is unable to produce its own gravity. However, light is altered by the density of the gravity around it.
Does light move slower in gravity?
Answer: The short answer is no, the speed of light is unchanged by gravity. If for example light travels from a distant star to Earth and passes by a black hole, the path of the light will get bent as it passes by the black hole, which will lengthen its travel time. The actual speed of light, though, is unchanged.
Does light create gravity?
Light has energy, energy is equivalent to mass, and mass exerts gravitational force. Thus, light creates gravity, i.e. the bending of space-time.
Can you create gravity without mass?
The only way to get gravity is with mass. The more mass, the more gravity you get. Without mass, you can’t have gravity. The force of gravity that we feel is actually just an acceleration towards the center of the Earth at 9.8 meters per second squared, or 1G.
Does light have mass?
Light indeed carries energy via its momentum despite having no mass. Since photons (particles of light) have no mass, they must obey E = pc and therefore get all of their energy from their momentum. Now there is an interesting additional effect contained in the general equation.
Why does gravity affect light if it has no mass?
It might be surprising to you to hear that gravity can affect light even though light has no mass. According to general relativity, gravity is actually caused by a curving of space and time. Since light travels in a straight line through straight spacetime, the curving of spacetime causes light to follow a curved path.
Does time create gravity?
Yes, time goes faster the farther away you are from the earth’s surface compared to the time on the surface of the earth. This effect is known as “gravitational time dilation”. It is predicted by Einstein’s theory of General Relativity and has by verified multiple times by experiments.
Is there anything faster than the speed of light?
No. The universal speed limit, which we commonly call the speed of light, is fundamental to the way the universe works. Therefore, this tells us that nothing can ever go faster than the speed of light, for the simple reason that space and time do not actually exist beyond this point.
Does a photon have gravity?
Photons are discrete, particle-like units of electromagnetic radiation, more commonly known as light. Unlike particles of matter, however, photons have no mass. It is surprising, then, to find that gravity—traditionally understood as the force attracting any two objects with mass—can affect light.