Black holes may vary in size and age but one thing is for sure they’re hungry. New black holes are being discovered all the time and there seems to be no realistic limits to the size they can grow to. The black hole is a stellar remnant the end result of a dying star that is so dense that not even light can escape its gravitational pull. Some of these are as old as the universe while others are being formed right this second. As the nearest black hole is three and a half thousand light years away. This closest neighbor isn’t in our solar system but it is in our own milky way galaxy and it’s called sagittarius-A. It’s a decent size totaling between one and four million solar masses by our best estimates before we delve into the biggest and baddest of the supermassive black holes.
A brief history of Black Holes
The concept of a black hole is a relatively new one and we knew about them well before we were about to actually see one with our own two eyes in 2019. Back in 1915 Einstein’s ‘General Theory of Relativity’ described that both space and time are intertwined and how mass bends space time producing gravity. A year later Carl schwartzschild offered a solution to Einstein’s equations noting that objects of sufficient mass would have an escape velocity exceeding the speed of light and would be unable to be observed by their very nature. His work pointed towards the existence of black holes and would later form the basis of the first model of one. Fast forward to 1939, Einstein publishes a paper seeking to prove that it was impossible for celestial objects to be so dense that their gravity prevents light from escaping. J.Robert oppenheimer ironically used the work of Einstein and Schwarzschild to propose the first working concept of a black hole that the continued contraction of a dying star under the influence of its own gravitational field could in fact create a body with an attraction force so intense that light cannot escape. If his name seems familiar it’s because oppenheimer became the head of the Manhattan Project after being brought over from Germany by the allies under operation paperclip. His research would lead to the development of atomic weapons.
The Planck Particle
It makes sense that to explore how big black holes can get we have to understand how small they can be. Plank particles are extraordinarily small black holes and are thought to be 1.14×10^(-34) meters in diameter. It’s actually measured in a unit called a planck length which is itself 1.6×10^(-35) or the equivalent to something like a millionth of a billionth of a billionth of a billionth of a centimeter. This is the scale where quantum foam is believed to exist. It’s the weird realm of quantum physics where laws are very different to our own world. Extremely minor wormholes open and close constantly giving space a rapidly changing foam-like structure. If we were ever able to harness the limitless energy of quantum foam just one cubic centimeter of empty space would be enough to boil the earth’s oceans.
Can the fizzle out?
Before one of these plant particles approaches the earth it’s thought that the particle would evaporate through a process called ‘Hawking Radiation’ described by its namesake the great man himself theoretical physicist and candidate for the smartest man to ever exist Stephen Hawking. Though he passed away in 2018 perhaps his greatest legacy is something so simple taking a black hole’s temperature. Using a combination of Einstein’s ‘Theory of Relativity’ and ‘Quantum Mechanics’ he was able to explain how both come into play at the threshold of an event horizon, the point in a black hole where light cannot escape. Hawking Radiation is a thermal release spontaneously emitted by a black hole relative to its mass and gravity. It is a byproduct of the conversion of quantum vacuum fluctuations into pairs of particles,one being expelled by the black hole and a matching anti-particle being driven into it. The release of this radiation reduces the mass and energy of black holes ever so slightly. Regular-sized black holes dissolve so slowly that their lifespan would likely exceed the time taken to find the nearest black hole and combine with it. A black hole with a singular soul and mass will last 10^(67) years, an extremely long time. Supermassive black holes can take up to 10^(100) years to dissolve however micro black holes likely don’t last that long.
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