I realize it’s been a couple months since my last post on Gravitational Waves, where I said that I would be posting about black holes next. I had a lot happen in the past couple months that I had to deal with before I could start focusing on blogging again. Today, I will give a brief introduction to black holes, and the next post will go into further detail. Stay tuned, and stay patient 🙂
There are only three things you need to know to understand a black hole and that is it’s 1) mass, 2) spin, and 3) electric charge.
By definition a black hole is an object whose escape speed is the speed of light. Escape speed is the speed it takes for an object to escape gravity (the curvature of spacetime). In order for an object to escape a black hole, it must reach the speed of light. Therefore, light itself cannot escape a black hole. The speed of light can be thought as the “speed limit” of the universe.
It is known that an object that comes into contact with a black hole gets sucked in by it’s gravity and cannot escape. Once the object is sucked in, it is no longer visible and all of it’s information is believed to be lost forever, as if it never existed.
Although a black hole’s gravity is a very strong force, an object that enters into it’s orbit is able to escape as long as it does not cross the event horizon of the black hole. Before reaching the event horizon, gravity is weak. Thus, a slight push would allow for an object to escape the black hole. Once that object reaches the event horizon, it has reached a point of no return. Gravity becomes so strong, that the object would have to have that much stronger of a push in order to get out. Once the object reaches the singularity of the black hole- the small, dense skeleton of the dead star and the source of strong gravity, that is when the object needs a push faster than the speed of light to escape, and that cannot happen. This is why we remain oblivious as to what goes on inside of a black hole, because an object that falls past the event horizon is said to never leave, giving us zero information about what’s inside.
Picture from Shane Larson’s blog; who provides a lucid, and entertaining explanation of everything science!
That’s it for now, stay tuned for more 🙂
This post is part of a series, for links to other posts, click here!