Kugelblitz, The Theoretical Black Hole Made Of Light
You might think light is the antithesis of a black hole, but that may not be the case. Physicists say that it should theoretically be possible to create a black hole out of nothing but light. This would be called a kugelblitz, named after a German word meaning "ball lightning." Usually, black holes are created when a huge amount of matter is packed into a tiny space, increasing its density. But since light has no mass, how could it become a black hole? Light may be mass-less, but it does contain energy. Einstein's E=mc^2 tells us that gravity treats the energy stored in matter and the mass in matter the same -- it pulls on them both. But you'd need a lot of light to actually make a black hole out of it. To create an Earth-sized kugelblitz, you'd need all of the light emitted over 10 years by all the stars within 350 light-years of Earth. We've collected some awesome videos on this topic. Watch them now to learn more.
from SciShow Space
Key Facts In This Video
Physicists say it should be possible to create a black hole out of nothing but light, which is called a kugelblitz. (0:03)
Usually, a black hole is formed when a lot of matter is packed into very little space, which increases its density. (0:22)
To create a kugelblitz, you would need all of the light put out over 10 years by all the stars within 350 light-years of Earth. (2:06)