What is a Black Hole?
First of all, it is not physically possible to see a black hole. The term applies to a theoretical place in the universe that forms when a star’s mass experiences gravitational collapse. The mass of the star compresses into such a small space nothing can exit the hole (not even light). The theory has its basis in the Theory of General Relativity (Einstein).
As we mentioned, this phenomenon has never been observed. But scientists have predicted the existence of black holes, some using alternate theories to account for what they have observed. One of the theories is called magnetospheric eternally collapsing objects. This particular idea doesn’t use what is called the spacetime singularity that may be at the center of the black hole.
Before Albert Einstein expressed his theories in detail scientists believed that massive celestial objects might have enough pull to draw light into them. One theory even proposed an object moving at the speed of light and being invisible. But these were sometimes called dark stars.
Physicists worked with Einstein’s Theory of General Relativity to come up with additional details about the mass of spherical objects. To understand how this theory relates to black holes it is necessary to understand such terms as “event horizon” and “escape velocity.” From the radius of the sphere it would be necessary to attain the speed of light in order to escape that sphere’s gravitational pull.
Black Hole as a Theory
As years went by, physicists worked to prove that stars with a certain mass would have to collapse. Others thought there was a part of the makeup of stars that would prevent complete collapse. More than 20 years after Einstein published his theory scientists would come up with the theory that a star with enormous mass could indeed collapse. This idea introduced the concept of redshift.
In more recent years scientists have come closer to proving that black holes were indeed tied to general relativity. They also found that once the process of collapse started there would be no way to stopping it. Modern space scientists, including Stephen Hawking, have proposed that black holes can emit radiation, even while nothing else will escape.
As far as the majority of astronomers and physicists are concerned, black holes do exist. Some scientists have even predicted that the matter collapsing into a black hole would have to appear somewhere in the universe.
In summary, it seems that for a black hole to exist the object would have to have mass concentrated into such a small radius that nothing would be able to escape. It would take movement faster than the speed of light and no object can move that fast. The gravitational pull of the mass would be so great that everything, including light, would be pulled back and into the core.
Two more interesting facts about black holes:
• The phrase was invented by a man named Wheeler.
• There is probably no minimum or maximum mass an object must have to form a black hole.