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8

"According to Newton's law the negative mass should be repelled" -- Nope, in both Newtonian physics and in general relativity, negative mass would be attracted gravitationally to positive mass, although negative mass would exert a repulsive gravitational effect on positive mass (but if the negative mass is small compared to the mass of the black hole this ...


0

I think your guess is correct for mass-less "rockets" (a photon), but for real rockets (with mass m), the pertinent equations are the same one would use to calculate a satellite's orbit around the earth, at an altitude = to the radius of the earth, and making the velocity a little larger. Substitute the mass of the rocket and the equivalent mass of the ...


-1

I believe the issue is that external information from infinity will have difficulty catching up to the infalling object, ie, the light cones will not intersect. I have seen this answered in detail based on an infalling object having passed the event horizon, but since that can't happen, the person answering the question has oversimplified the problem. One ...


9

The bright parts around the black hole are the accretion disk, which is in reality just a flat disk in the equatorial plane similar to the rings of Saturn, but is distorted visually by gravitational lensing. You can see a page here that gives some code for creating images using ray-tracing of light rays in curved spacetime, which offers a more schematic ...


0

The simple answer is that general relativity does not, and indeed cannot, tell us what happens to the matter when it is all compressed into the singularity. We commonly describe black holes using the Schwarzschild metric because it's a relatively simple metric. However the Schwarzschild metric only describes the end result and doesn't tell us anything about ...


1

There are frameworks in physics, dimensional and energetic frameworks. There is the classical framework which has classical theories of mechanics and electrodynamics etc, where the dimensions are compatible with the meters/seconds/kilograms measures. There is the quantum framework which has quantum mechanics, quantum electrodynamics and quantum field ...


1

There is a relatively new theory (2012) called the firewall theory, that says that at the event horizon there is a huge "wall of fire" as such. This is because quantum entangled particles that cross the horizon (or one half of a pair of entangled particles) becomes tricky and starts breaking laws like the monogamy of entanglement. So a group of physicists ...


10

This is explained thoroughly in Thorne's book "The Science of Interstellar". There were two scientific papers based on the simulations: One in physics and one in computer rendering. The two circles are caused by gravitational lensing by a very rapidly spinning black hole. The radius of this black hole is 150 million kilometers with a mass of 100 million ...


20

First note that this is a fictional movie and the image is an artist's impression, not a detailed simulation. The public seems to think the movie is some sort of fictionalized documentary, which it never claimed to be. That said, the image is qualitatively conveying some of what happens near a black hole. The diagonal disk is the accretion disk -- this is ...


4

The horizontal circle is probably the accretion disc of the black hole. The vertical circle might depict the effect of gravitational lensing (although I am not sure this depiction is accurate).


2

One thing to note is that this horizon would only be present in an idealized eternal black hole, for a realistic non-rotating black hole formed by a collapsing star the Kruskal-Szekeres diagram would look more like the right-hand diagram below (from Gravitation by Misner, Thorne and Wheeler), where the gray area represents the interior of the star and the ...


0

For the first part you are correct but it is a bit of an illusion. If say a person fell into a black hole, then there are two perspectives: From the perspective of the person, they fall straight in (ignoring whether they survive to observe it or not). From an outside observer the person appears to slow down as they approach the event horizon of the black ...


3

The answer is it depends on which observer we are talking about - an observer "with" the collapsing mass sees it and them crushed to a singularity; an external observer "sees" (though see below) the mass frozen just at the event horizon. In GR and a standard black hole, there is only one future for a mass that finds itself at or inside the event horizon, ...



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