just so you know, gravity does generate light, indirectly.
Every star has a constant struggle between it’s radiation force, that tends to make the star expand, and its gravitatory force, that tends to make it collapse.
Whenever a star runs out of fusable fuel, radiation stops, and gravity makes it collapse. But guess what? Stars are made of gas. What happens if you reduce the volume of a gas, while keeping the same amount of gas?
Bingo, pressure and temperature increase. More temperature = reaching enough kinetical energy to beat the nuclear repulsive forces = fusion starts again = radiation is restored = star stabilizes again = produces light.
Let’s collapse all of this together.
Gravity = Light, oh yeah.
and yes, Gravity can bend light. Light is made of photons. Photons are waves, and particles at the same time. In wave form, they travel so fast and have such minimal mass that they are virtually unaffected by gravity, however, really intense gravitatory fields, as Tim pointed, black holes, CAN exert enough force over the photons to trap them.
And stars have 3 possible deaths, just so you know, and don’t go around saying bullshit.
Any star with less than 3 times the mass of our Sun, will burn Hydrogen, then collapse, reactivate and burn Helium (red giant), collapse again, inflate into a supergiant, cool down, and burn Carbon, collapse again, burn Oxygen, at which point, it’ll become a molten Iron core that is unfusable, and will slowly radiate away whatever little energy it has left (White dwarf).
Stars with between 3 and 10 times the mass of our sun will collapse to a point where the nuclear repulsive forces are defeated, and matter is collapsed into a state where there are no empty space between atoms, read, a neutron star, a superdense entity that often spins sending ‘pulses’ of energy like a lighthouse, called ‘Pulsar’.
Stars with more than 10 times the mass of the Sun will pull a cataclysmic explosion, a supernova, expelling its outer layers, while the core collapses past a neutron star into a black hole.
And, Black holes do emit energy. Hawking’s radiation and such. Of course, this is all purely theoretical, but so far it complies with actual observation.
Also, what WotW said is part true. Many galaxies, as well as outer-universe ancient structures known as Quasars, have int heir cores some kind of super-powerplant, powered by a super blackhole.
Also, as for light bending, refraction does that, as Tim said, as well (although the sky being blue thing and such is not caused by refraction, but by Rayleigh Scattering)
If the light goes through any media that has a refraction index gradient, such as, air at different temperatures (air in contact with a hot road, hot near the road, colder above), will cause the light’s trajectory to bend as it goes through the media. That’s what causes really hot roads to look like they have melted when you drive on them.
So yeah, I suggest having a look at a Physics book before saying random shit again.