All Questions
30
questions
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Can the inertia factor of a black hole be used to infer its density profile?
The Sun's inertia factor of ~0.07 suggests a stark contrast between the density of its outer shells (very low density) and its core (very dense). The same applies to the rest of the solar system. ...
- 11
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2
answers
289
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Understanding the Singularity of Black Holes [duplicate]
Could someone please explain how we know the singularity has an infinite density and zero size/volume? From reading around online black holes have a defined radius (the event horizon) but this isn't ...
- 565
1
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2
answers
596
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A black hole made of ordinary water?
Years ago I read a book about black holes. It said it is theoretically possible to make a black hole from ordinary-density materials, like tap water. It would take a lot -- about the size of a galaxy ...
- 265
1
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3
answers
2k
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Why does General Relativity predict that singularities are infinitely dense?
From my understanding of general relativity, energy curves spacetime to produce an effect that we call gravity. The greater the concentration of energy, the greater the curvature and hence the greater ...
1
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1
answer
113
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Definition of density of black holes
For a blackhole of mass $M$, radius $R$ and Schwarzschild radius $R^*$ (where $R<R^*$), its density $\rho$ is defined as $$\rho=\frac{M}{(R^*)^3}.$$
One reason I read for using the Schwarzschild ...
- 4,235
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0
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36
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Black Hole Mass Density Ratio [duplicate]
(1) The density of water increases as one approaches the bottom of the sea.
(2) The density of neutron stars also increases from crust to core.
Black holes with greater mass have a larger radius and ...
- 127
0
votes
1
answer
191
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Black hole mass
It has been taught to us that since the black holes have finite mass, their gravitational force is also finite, which totally fits. The Black hole anyhow has a singularity at it's center which is ...
- 195
2
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4
answers
308
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Is there a limit to the amount of mass we can concentrate in a region of space?
Black holes are solutions to Einstein's Field Equations. Black holes contain a singularity hidden from the outer universe. As I understand, these singularities are infinitesimal and contain a very ...
- 1,266
1
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1
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151
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Black hole and its density
I'm an amateur to astrophysics but I'm slowly teaching myself things and I have these three doubts.
How does more compression relate to a stronger gravitational pull. Like, when we say that a black ...
- 131
3
votes
3
answers
1k
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BH singularity? Infinite density
How can the density of a region of space go from finite density to infinite when there are no numbers larger than any Aleph0 number but smaller than any Aleph1 number (no decimal point in front of it, ...
1
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1
answer
117
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Silly question about Schwarzschild Black holes and scientific communication
Well, in scientific communication literature often we encounter the following phrase about black holes:
A Black Hole is a body that have infinite curvature and infinite density
So, with basic GR ...
- 3,085
1
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1
answer
97
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Where is mass density information of a Black Hole?
Have read that all the information of a black hole is contained on the Event Horizon. Does that include mass density of interior as a function of position? The shape of an event horizon depends on the ...
- 2,728
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1
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125
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What is a black hole made of? [duplicate]
Since we know white dwarfs are made of electrons and neutrons stars are made of neutrons and quark gluon plasma. What can we say about the black hole in this sense since its properties are far ...
- 21
3
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2
answers
2k
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What kind of matter are black holes made of?
Imagine a black hole originally formed from, for example, Rubidium atoms. On the other hand, one made from, for example, Helium atoms. Will it be there any difference between the two? Or perhaps once ...
- 2,982
0
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1
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192
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Properties of singularity
I read that singularity is point in space where is infinite gravitational force caused by collapsing something very big into something very small.
How can something with certain mass (star few ...
- 117