Black Holes
I’ve seen such horror,
and such love.
Juxtapositions of
rules and regulations,
precepts upon precepts.
I’ve watched from sidelines
wondering if God
divided up matters
as such – sterile and cold
rules to be followed.
Intent within souls
and hearts seeking light
should be valued above all.
In some men
black holes reside.
I’ve seen them fought.
I’ve seen men devoured.
And even still,
I’ve seen the rare soul
defy the odds
and reverse gravity itself.
rules and regulations,
precepts upon precepts.
I’ve watched from sidelines
wondering if God
divided up matters
as such – sterile and cold
rules to be followed.
Intent within souls
and hearts seeking light
should be valued above all.
In some men
black holes reside.
I’ve seen them fought.
I’ve seen men devoured.
And even still,
I’ve seen the rare soul
defy the odds
and reverse gravity itself.
A black hole is a region that exhibits such strong gravitation that nothing — not even particles or electromagnetic radiation such as light -- can escape from it. Despite its invisible interior, the presence of a black hole can be inferred through its interaction with other matter and electromagnetic radiation. If other stars are orbiting a black hole, their orbits can be used to determine the black hole's mass and location. The term was coined by journalist Ann Ewing in a 1964 report on a meeting of the American Association for the Advancement of Science, but when John Wheeler used it in a 1967 lecture it came into general use. But the idea was first put forward by John Michell in a 1783 letter to Henry Cavendish of the Royal Society and promoted in Pierre-Simon Laplace's 1796 book "Exposition du système du Monde," but it was removed from later editions since it was not understood how a massless wave such as light could be influenced by gravity. In 1915, Albert Einstein, who had earlier shown that gravity does influence light's motion, developed his theory of general relativity, which predicts that a sufficiently compact mass can deform spacetime to form a black hole. A few months later, Karl Schwarzschild found a solution to the Einstein field equations which describes the gravitational field of a point mass and a spherical mass (though its interpretation as a region of space from which nothing can escape was published by David Finkelstein in 1958). At the Schwarzschild radius, this solution becomes singular, meaning that some of the terms in the Einstein equations became infinite. In 1924 Arthur Eddington showed that the singularity disappeared after a change of coordinates, but it was not until 1933 that Georges Lemaître realized that this meant the singularity at the Schwarzschild radius was an unphysical coordinate singularity. In 1931 Subrahmanyan Chandrasekhar had calculated that a non-rotating body of electron-degenerate matter above a certain limiting mass has no stable solutions, but Eddington insisted that the collapse would be stopped by some yet unknown mechanism. (In fact, a white dwarf star slightly more massive than the Chandrasekhar limit will collapse instead into a stable neutron star; but in 1939, J. Robert Oppenheimer predicted that neutron stars also would collapse into black holes for the reasons presented by Chandrasekhar.) In 1958, Finkelstein identified the Schwarzschild surface as an event horizon, "a perfect unidirectional membrane: causal influences can cross it in only one direction. In 1963, Roy Kerr found the exact solution for a rotating black hole. Two years later, Ezra Newman found the axisymmetric solution for a black hole that is both rotating and electrically charged. But until the discovery of pulsars in 1967, which were shown by 1969 to be rapidly rotating neutron stars, black holes and neutron stars alike were regarded as theoretical curiosities; the discovery of pulsars showed their physical relevance and spurred a further interest in all types of compact objects that might be formed by gravitational collapse. In the late 1960s Roger Penrose and Stephen Hawking proved that singularities appear generically, and in 1974 Hawking showed that quantum field theory predicts that black holes should radiate like a black body with a temperature proportional to the surface gravity of the black hole. Unfortunately, quantum field theory holds that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is on the order of billionths of a kelvin for black holes of stellar mass, making it essentially impossible to observe. Nonetheless, on 11 February 2016, the Laser Interferometer Gravitational-wave Observatory (LIGO) announced the first-ever observation of gravitational waves; because these waves were generated from a black hole merger it was the first direct detection of a binary black hole merger.
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