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What are the hypotheses on which primordial black holes are thought to be smaller? If the primordial distribution of matter is really inhomogeneous, for exampl

What are the hypotheses on which primordial black holes are thought to be smaller? If the primordial distribution of matter is really inhomogeneous, for example with a gradient of density from the center of the "blob" to the rim, with the center being very "bloated", would that give birth to supermassive black holes (or maybe one) at the center and smaller ones among the rest of the soup?

slowmovintarget 2y ago
> Depending on when exactly they formed, primordial black holes could have masses as low as 10^-7 ounces (10^-5 grams), or 100,000 times less than a paperclip, up to about 100,000 times greater than the Sun. [1] Also, very small ones could have already evaporated. > Hawking calculated that any primordial black hole with a mass greater than 10^12 pounds ([10^12 kilograms]; that’s far less than the mass of any planet, dwarf planet, and most named asteroids and comets in our solar system) could still be around today, while those less massive would have already disappeared. [1] The theories for the likely formation of primordial black holes have been around since the seventies, and they all point to small black holes (compared to, for example, the supermassive black holes at the centers of galaxies). The Wikipedia page has a better history of the thinking around PBHs.[2] What's remarkable about these new findings is that the age of these quasars being studied suggests that, though they are supermassive, and just like other quasars that are far younger, they appear "the same" and must be labeled "primordial" because of their age. (This is pointed out in the last paragraph of the original article.) [1] https://www.astronomy.com/science/what-are-primordial-black-holes/ https://www.astronomy.com/science/what-are-primordial-black-... [2] https://en.wikipedia.org/wiki/Primordial_black_hole https://en.wikipedia.org/wiki/Primordial_black_hole

slowmovintarget 2y ago

> Depending on when exactly they formed, primordial black holes could have masses as low as 10^-7 ounces (10^-5 grams), or 100,000 times less than a paperclip, up to about 100,000 times greater than the Sun. [1] Also, very small ones could have already evaporated. > Hawking calculated that any primordial black hole with a mass greater than 10^12 pounds ([10^12 kilograms]; that’s far less than the mass of any planet, dwarf planet, and most named asteroids and comets in our solar system) could still be around today, while those less massive would have already disappeared. [1] The theories for the likely formation of primordial black holes have been around since the seventies, and they all point to small black holes (compared to, for example, the supermassive black holes at the centers of galaxies). The Wikipedia page has a better history of the thinking around PBHs.[2] What's remarkable about these new findings is that the age of these quasars being studied suggests that, though they are supermassive, and just like other quasars that are far younger, they appear "the same" and must be labeled "primordial" because of their age. (This is pointed out in the last paragraph of the original article.) [1] https://www.astronomy.com/science/what-are-primordial-black-holes/ https://www.astronomy.com/science/what-are-primordial-black-... [2] https://en.wikipedia.org/wiki/Primordial_black_hole https://en.wikipedia.org/wiki/Primordial_black_hole