The Origin and Its Meaning
A "black hole" is a small region at the center of a galaxy, the region exhibiting huge gravitational attraction.
· The term "black" is because not even light can escape the gravitation. The black hole allows nothing out; it is literally black.
· The term "hole" is because it "sucks" the surrounding matter into it as if it were a bottomless pit, a hole.
Such a black hole should eventually suck everything into it, as follows. Because gravitation is proportional to mass:
· As the hole sucks in more mass its gravitational attraction becomes even stronger.
· And, as its gravitational attraction becomes even stronger it can suck mass in even more strongly.
But, black holes appear to affect only the region near them. Most of a black hole's galaxy acts as if there were no black hole, merely an ordinary gravitating mass, there.
This behavior is readily explained because ...
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... The Origin and Its Meaning
does for physics what Euclid did for geometry -- it supersedes mere empirical conclusions with derivation of all of physics.
20th Century physic's relativity shows that the linear Newton's 2nd Law of Motion, F = m´ a, becomes non-linear at large speeds.
Similarly the derivation of gravitation in The Origin and Its Meaning shows that gravitation becomes non-linear at large accelerations.
· In strong gravitational fields the strength of the action increases hyperbolically as the field increases.
· Black holes exhibit such strong gravitational fields near the black hole. Farther out the field is much less and the gravitation is normal.