Linked Questions
11 questions linked to/from Does the radio (between two co-moving astronauts) stop working when crossing the event horizon?
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How does light behave within a black hole's event horizon?
If the event horizon of a black hole is the distance from the center from within which light cannot escape, imagine a person with a flashlight falls into the black hole.
He points his flashlight in a ...
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Falling into a black hole
I've heard it mentioned many times that "nothing special" happens for an infalling observer who crosses the event horizon of a black hole, but I've never been completely satisfied with that statement. ...
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Taking selfies while falling, would you be able to notice a horizon before hitting a singularity?
I am generally interested in the role of "pings"(0a) between participants (a.k.a. "signal roundtrips"(0b), as familiar for instance from Synge's "five point curvature detector") in the determination ...
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Will a distant observer really see an object that has fallen close to a black hole freeze in time?
I'm currently taking my first course in general relativity, and I was wondering:
We know from the schwarzschild metric that for a (far away) observer looking at an object falling towards a black hole, ...
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What do you feel when crossing the event horizon?
I have heard the claim over and over that you won't feel anything when crossing the event horizon as the curvature is not very large. But the fundamental fact remains that information cannot pass ...
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Is the event horizon locally detectable?
There are two conflicting ideas.
According to the traditional view, determining the location of the event horizon of a black hole requires the knowledge of the whole future behaviour of the black ...
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Trajectory of a photon beyond the event horizon
So this random question popped up in my mind. As we know the photons get deflected if they pass in the vicinity of a black hole. At the event horizon(right before it), they form the photon sphere. The ...
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Will the photon ever reach the object falling into the black hole?
The problem is 1-D: there is an object in position $r_\text{obj}$ falling into a Schwarzschild black hole with velocity $V_\text{obj}$, followed by a light signal at position $r_p$. Diagram below:
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Birkhoff's theorem and Schwarzschild vacuum solution [duplicate]
Birkhoff's theorem states that any spherically symmetric solution of the vacuum field equations must be static and asymptotically flat, but the well-known Schwarzschild solution satisfies these ...
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Question about two people falling into a black hole
I’ve heard that IIRC if you have two people fall into a black hole such that they are just out of reach of each other, due to the way that geometry in the black hole works, they will forever stay out ...
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If the escape velocity for a body that is very close to a BH is near $c$ but not $c$ can it move away a little bit before it falls inside the BH?
The escape velocity from a common gravtational attractor means that a body lounched away from the attractor will never turn back. But in the case of a BH at the event horizon this escape velocity is $...
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