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.
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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)