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I've never understood why the term black holes are widely used to describe what is actually a black star or dark star. I mean why name something just because of its extreme space curvature effects? In fact, is the term "hole" in "black hole" even accurate? An object, any object would create a space curvature in all 3D axis' XYZ not a hole which implies a 2D space curvature, and by "implies a 2D space curvature" I mean the gravitational space-time distortion diagrams which many people see as a hole, so space curvature having a point a to point b and not a sphere that it would be.

Update
Even Dr. Becky thinks the same

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    $\begingroup$ One of the key features of a star is the presence of fusion. So far as we know, fusion does not occur in black holes. Furthermore, the escape velocity of a black hole's gravity well is the same as the speed of light (or higher, not sure on that fact). By its nature we have no idea what's going on inside. It emits no radiation (if we exclude Hawking Radiation) so it appears black. Geometrically speaking, it is modeled as an infinitely deep "hole" in spacetime, hence "black hole". $\endgroup$ Nov 22, 2023 at 1:44
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    $\begingroup$ Why does "hole" imply a 2D space curvature? In General Relativity, gravity is 4D spacetime curvature. $\endgroup$
    – PM 2Ring
    Nov 22, 2023 at 8:08
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    $\begingroup$ A rose by any other name would smell just as sweet. $\endgroup$ Nov 23, 2023 at 4:16
  • $\begingroup$ "Dark Star" is taken! en.wikipedia.org/wiki/Dark_Star_(film) $\endgroup$ Nov 23, 2023 at 13:15
  • $\begingroup$ Did you watch the video that you linked in your post? The entire video is about the answer to your question. $\endgroup$
    – Lee Mosher
    Nov 25, 2023 at 16:16

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The hypothetical object where gravity is so strong that even light cannot escape was indeed first called "dark star". It was first named as such by John Michell in the 1700s. See Wiki. Note general relativity dates from the early 1900s, so John Michell's dark stars were based on Newtonian gravity, in which theory it is unclear how gravity interacts with light.

Wiki also gives how black holes got their name:

In December 1967, a student reportedly suggested the phrase "black hole" at a lecture by John Wheeler; Wheeler adopted the term for its brevity and "advertising value", and it quickly caught on, leading some to credit Wheeler with coining the phrase.

The name 'dark star' (or 'black star') undoubtedly fell out of use because black holes are not stars. Stars shine, they undergo nuclear fusion in their cores, etc. Nothing of that sort happens in black holes.

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  • $\begingroup$ Also note that "black holes" are steady-state solutions of the GR equations (i.e. it is a priori unclear when and if the black-hole state can actually be reached in finite time). Coming from the stellar physics side, there were originally collapsing stars, "collapsars", which turned out to be the astrophysical black holes and which formed in finite time. Nowadays this distinction is often forgotten. $\endgroup$ Nov 22, 2023 at 15:43
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    $\begingroup$ Neutron stars don't undergo fusion, yet they are called "stars". (Personally, I'm not thrilled with that.) $\endgroup$ Nov 23, 2023 at 4:15
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    $\begingroup$ @AtmosphericPrisonEscape The notion of a "collapsar" arises from a total misunderstanding of the timescales involved. An astrophysical collapse to a black hole will approach its steady state exponentially. Within a fraction of a second (as measured by an external observer) the number of photons emitted by the collapsing material expected to reach external observers for the rest of eternity drops below 1. After this only things that can be observed from the matter are its mass and charge monopole moments, and its mass current dipole moment, and the resulting object has become ... $\endgroup$
    – TimRias
    Nov 23, 2023 at 14:02
  • $\begingroup$ ... indistinguishable from a Kerr-Newman black hole with corresponding mass, charge, and spin that has been there forever. $\endgroup$
    – TimRias
    Nov 23, 2023 at 14:03
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In theory, if you could observe the gravitational collapse of a star, you'd see it accelerating away from you regardless of what direction you observed it from. Just as if it fell into a hole.

This is closely related to the misidentification of the radial parameter in the Schwarzschild geometry with "radius". If you draw a circle around the center of such a geometry, the radial parameter is the circumference of the circle divided by $2\pi$. The distance between such circles is greater than the difference between their radial parameters, just as you'd expect for a hole.

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