All Questions
Tagged with spacetime black-holes
322
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Why do black holes remain? [closed]
When we think about black holes as not containing matter but being regions of warped spacetime, I can't think why they don't revert to being Euclidian space more quickly. This is because I can see how ...
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Why are distances to event horizons linear with mass when gravitational effects fall off as $1/r^2$?
Black holes' gravitational effects fall off as $1/r^2$, but their event horizon grows linearly with increasing mass. $R$ (event horizon) grows the same rate as $M$ (mass of black hole). Okay lets ...
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How can the black hole information paradox be valid if from an oustide perspective nothing can ever enter a black hole [duplicate]
I base my question on the following premise: from the perspective of an outside observer nothing can ever enter a black hole, due to the time dilation.
If that premise is true, then why the ...
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Is the gravitational tidal force equivalent to expanding space?
If you fall towards a black hole, the particles in front and the back of you, in the direction of the center, are accelerating away from you. So, seen from a freely frame, can we say that space is ...
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Is it possible the Black Holes to be pure deformations in the fabric of spacetime and not an effect of super-dense matter?
Is there any theory in the literature that supports this hypothesis that BHs in their center do not have a super-dense matter singularity but are pure deformations in the fabric of spacetime itself or ...
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What does a black hole accretion disk look like edge on?
We have images of two black holes so far, with representations showing a deep black center where in-falling matter vanishes- how would that look side on? Would it be possible to even obtain an image ...
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Would our orbit really remain the same if the sun were a black hole of equal mass?
There seems to be an idea floating around that the sun could be replaced by anything of equal mass with no consequence to our orbit.
It seems to me that if the mass of the sun were confined to a ...
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Using gravity to beat event horizon of black hole [duplicate]
So I know it's impossible for an object A to escape a black hole once it has crossed the event horizon, but what if it had help from the outside? Is it theoretically possible for a massive enough ...
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Why does Kip Thorne claim spacetime warping itself contains energy?
Kip Thorne, in this public lecture, says
that a black hole is kept together by the energy of the warping of space.
Quote around 8:00-8:30 :
"in this case, the energy [which keeps a black hole ...
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What distant observer would see if spaceship remains insitu just outside event horizon?
Imagine 2 spaceships found themselves just outside the event horizon of a blackhole, spaceship A tries to remain in place relative to the black hole while B accelerates around the blackhole. To a ...
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How can I make sense of black hole complementarity if the universe consist of one manifold and observers are not married to coordinates?
I'm reaching way over my head here, so bare in mind my knowledge base is at best upper undergraduate. This is, unfortunately, yet another byproduct of discussions in this page that is itself a ...
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Why does Leonard Susskind draw constant time slices around a black hole as lines passing through the origin at zero?
In this video Inside Black Holes by Leonard Susskind,
why does he draw the constant time slice as lines passing through the origin at zero?
Something seems to be contradicting to have constant time ...
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Gravitational waves of objects with the same angular momentum
So I read that gravitational waves are produced when the quadrupole moment of a system is not symmetric.
What does it actually mean for the quadrupole moment to be asymmetric? If there are two black ...
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Do test particles initially comoving with a black hole accelerate away from it?
This question feels ridiculous, but I really am confused. If you Google Image search "schwarzchild light cones" it shows how, relative to the frame comoving with the singularity, the speed ...
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Spacetime inside the horizon of a black hole
According to Susskind a bit of information crossing the event horizon of a black hole instantaneously encounters the singularity. Also, time appears to gradually slow down for an object approaching ...
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