Up until the mid-twentieth century many scientists had trouble accepting that a collapsed star could have gravity so powerful that nothing could ever escape.
Russian scientists called them “frozen stars” or “labor camps,” after the infamous penal camps of the Soviet Union. Some of the hip American scientists call them “Hotel California,” borrowing a name from the Eagles.
In 1967 John Wheeler, a physicist from Princeton University, attended a conference on pulsars in New York. Wheeler discussed the probability that a star’s extreme collapse would create a “black hole” in space. Scientists had a new term they could work with and the research took off.
Up to then the toughest hurdle to overcome before everyone could accept black holes was the concept of a singularity, the “core” of a black hole.
A singularity is a mathematical concept that involves something is infinite in some way. Mathematicians have no trouble with this so long as it is not used to describe material things. You can not have an infinite amount of dollars in the bank. You can not have an infinite amount of marbles or anything else.
So how could the core of a collapsed star be infinitely small? How could it keep anything that falls in for an infinite amount of time?
But by the early 1970’s, the world saw great advances in black hole research, (the discovery of Cygnus X-1 for example), so the idea of black holes became easier to accept.
Thanks to many researchers like John Wheeler, (who worked with Stirling Colgate), Roger Penrose and Finkelstein, scientists had new and improved mathematical models to describe black holes. Eventually it was well accepted in the scientific community. Black holes were real.
And they kill space travelers…