As matter approaches a black hole, does it speed up?Does gravity propagate?Why does time get slow near a black hole?How does a gravity slingshot actually work?Can an astronaut ever reach a Black Hole theoretically?When you travel fast around a black hole, do you experience high speed yourself?Black hole darkness a result of gravity or temporal distortion?How can a supermassive black hole cause so much energy to enlighten its matter when its massive gravity prevents light to escape?Can a star eat a black hole?Does matter accelerate to the speed of light as it approaches the singularity?Is matter lost in a black hole?
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As matter approaches a black hole, does it speed up?
Does gravity propagate?Why does time get slow near a black hole?How does a gravity slingshot actually work?Can an astronaut ever reach a Black Hole theoretically?When you travel fast around a black hole, do you experience high speed yourself?Black hole darkness a result of gravity or temporal distortion?How can a supermassive black hole cause so much energy to enlighten its matter when its massive gravity prevents light to escape?Can a star eat a black hole?Does matter accelerate to the speed of light as it approaches the singularity?Is matter lost in a black hole?
$begingroup$
If so, how do we know it speeds up? Doesn't time slow down as gravity increases? If time slows down around a black hole, is it possible matter doesn't actually speed up?
black-hole gravity
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
add a comment |
$begingroup$
If so, how do we know it speeds up? Doesn't time slow down as gravity increases? If time slows down around a black hole, is it possible matter doesn't actually speed up?
black-hole gravity
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago
add a comment |
$begingroup$
If so, how do we know it speeds up? Doesn't time slow down as gravity increases? If time slows down around a black hole, is it possible matter doesn't actually speed up?
black-hole gravity
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
If so, how do we know it speeds up? Doesn't time slow down as gravity increases? If time slows down around a black hole, is it possible matter doesn't actually speed up?
black-hole gravity
black-hole gravity
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 3 hours ago
dwsteindwstein
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 3 hours ago
dwsteindwstein
1162
asked 3 hours ago
dwsteindwstein
1162
1162
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
dwstein is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago
add a comment |
$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago
$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago
$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
Take a simple example. If something falls freely towards a black hole along a radial path, and is observed by someone who is far from the black hole, its velocity (according to the distant observer) is given by
$$v = -left(1 - fracr_srright)left(fracr_srright)^1/2c, ,$$
where $r_s$ is the Schwarzschild radius and the negative sign just indicates an inward velocity with $r$ decreasing.
If you plot this function you will see that initially the magnitude of the velocity increases as $r$ decreases, but as $rrightarrow r_s$ then $v rightarrow 0$ and the falling object appears to come to a standstill (actually, because the light from the object is gravitationally redshifted, this may not actually be observed). However, if the velocity first increases and then slows to a standstill, then it must go through a maximum!
The maximum speed in this scenario is achieved at $r=3r_s$ and is $0.384c$.
Of course this story is different for different observers. If you are the falling object then your speed just keeps increasing through the event horizon and towards the singularity. On the other hand, an observer who was somehow able to hover just above the event horizon would measure the falling object's speed as just below $c$ as it passed.
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
$endgroup$
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
add a comment |
$begingroup$
The dilation of time is only relevant from the perspective of someone far away from the black hole. Close to the black hole time is still progressing forward at what would appear to be a normal rate to someone who is close to the black hole. The movie Interstellar had a great depiction this phenomenon, with the astronauts Copper and Brand on Miller's planet, near the black hole, spending only a few hours, but the astronaut Romilly aging decades as he remained far from the planet. Copper and Brand didn't experience any change in the passage of time, from their perspective.
Matter falling into a black hole would not experience any change in its perspective of time, so would not appear to change speed, other than what would be expected by the gravitational attraction.
answered 3 hours ago
Bob516Bob516
2228
$endgroup$
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
$begingroup$
Take a simple example. If something falls freely towards a black hole along a radial path, and is observed by someone who is far from the black hole, its velocity (according to the distant observer) is given by
$$v = -left(1 - fracr_srright)left(fracr_srright)^1/2c, ,$$
where $r_s$ is the Schwarzschild radius and the negative sign just indicates an inward velocity with $r$ decreasing.
If you plot this function you will see that initially the magnitude of the velocity increases as $r$ decreases, but as $rrightarrow r_s$ then $v rightarrow 0$ and the falling object appears to come to a standstill (actually, because the light from the object is gravitationally redshifted, this may not actually be observed). However, if the velocity first increases and then slows to a standstill, then it must go through a maximum!
The maximum speed in this scenario is achieved at $r=3r_s$ and is $0.384c$.
Of course this story is different for different observers. If you are the falling object then your speed just keeps increasing through the event horizon and towards the singularity. On the other hand, an observer who was somehow able to hover just above the event horizon would measure the falling object's speed as just below $c$ as it passed.
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
$endgroup$
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
add a comment |
$begingroup$
Take a simple example. If something falls freely towards a black hole along a radial path, and is observed by someone who is far from the black hole, its velocity (according to the distant observer) is given by
$$v = -left(1 - fracr_srright)left(fracr_srright)^1/2c, ,$$
where $r_s$ is the Schwarzschild radius and the negative sign just indicates an inward velocity with $r$ decreasing.
If you plot this function you will see that initially the magnitude of the velocity increases as $r$ decreases, but as $rrightarrow r_s$ then $v rightarrow 0$ and the falling object appears to come to a standstill (actually, because the light from the object is gravitationally redshifted, this may not actually be observed). However, if the velocity first increases and then slows to a standstill, then it must go through a maximum!
The maximum speed in this scenario is achieved at $r=3r_s$ and is $0.384c$.
Of course this story is different for different observers. If you are the falling object then your speed just keeps increasing through the event horizon and towards the singularity. On the other hand, an observer who was somehow able to hover just above the event horizon would measure the falling object's speed as just below $c$ as it passed.
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
$endgroup$
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
add a comment |
$begingroup$
Take a simple example. If something falls freely towards a black hole along a radial path, and is observed by someone who is far from the black hole, its velocity (according to the distant observer) is given by
$$v = -left(1 - fracr_srright)left(fracr_srright)^1/2c, ,$$
where $r_s$ is the Schwarzschild radius and the negative sign just indicates an inward velocity with $r$ decreasing.
If you plot this function you will see that initially the magnitude of the velocity increases as $r$ decreases, but as $rrightarrow r_s$ then $v rightarrow 0$ and the falling object appears to come to a standstill (actually, because the light from the object is gravitationally redshifted, this may not actually be observed). However, if the velocity first increases and then slows to a standstill, then it must go through a maximum!
The maximum speed in this scenario is achieved at $r=3r_s$ and is $0.384c$.
Of course this story is different for different observers. If you are the falling object then your speed just keeps increasing through the event horizon and towards the singularity. On the other hand, an observer who was somehow able to hover just above the event horizon would measure the falling object's speed as just below $c$ as it passed.
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
$endgroup$
Take a simple example. If something falls freely towards a black hole along a radial path, and is observed by someone who is far from the black hole, its velocity (according to the distant observer) is given by
$$v = -left(1 - fracr_srright)left(fracr_srright)^1/2c, ,$$
where $r_s$ is the Schwarzschild radius and the negative sign just indicates an inward velocity with $r$ decreasing.
If you plot this function you will see that initially the magnitude of the velocity increases as $r$ decreases, but as $rrightarrow r_s$ then $v rightarrow 0$ and the falling object appears to come to a standstill (actually, because the light from the object is gravitationally redshifted, this may not actually be observed). However, if the velocity first increases and then slows to a standstill, then it must go through a maximum!
The maximum speed in this scenario is achieved at $r=3r_s$ and is $0.384c$.
Of course this story is different for different observers. If you are the falling object then your speed just keeps increasing through the event horizon and towards the singularity. On the other hand, an observer who was somehow able to hover just above the event horizon would measure the falling object's speed as just below $c$ as it passed.
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
answered 2 hours ago
Rob JeffriesRob Jeffries
55.4k4114178
55.4k4114178
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
add a comment |
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
I take it this is for falling from infinity?
$endgroup$
– Acccumulation
32 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
$begingroup$
For this question, in the absence of a yes or no there is little to no validity in the details.
$endgroup$
– John
21 mins ago
add a comment |
$begingroup$
The dilation of time is only relevant from the perspective of someone far away from the black hole. Close to the black hole time is still progressing forward at what would appear to be a normal rate to someone who is close to the black hole. The movie Interstellar had a great depiction this phenomenon, with the astronauts Copper and Brand on Miller's planet, near the black hole, spending only a few hours, but the astronaut Romilly aging decades as he remained far from the planet. Copper and Brand didn't experience any change in the passage of time, from their perspective.
Matter falling into a black hole would not experience any change in its perspective of time, so would not appear to change speed, other than what would be expected by the gravitational attraction.
answered 3 hours ago
Bob516Bob516
2228
$endgroup$
add a comment |
$begingroup$
The dilation of time is only relevant from the perspective of someone far away from the black hole. Close to the black hole time is still progressing forward at what would appear to be a normal rate to someone who is close to the black hole. The movie Interstellar had a great depiction this phenomenon, with the astronauts Copper and Brand on Miller's planet, near the black hole, spending only a few hours, but the astronaut Romilly aging decades as he remained far from the planet. Copper and Brand didn't experience any change in the passage of time, from their perspective.
Matter falling into a black hole would not experience any change in its perspective of time, so would not appear to change speed, other than what would be expected by the gravitational attraction.
answered 3 hours ago
Bob516Bob516
2228
$endgroup$
add a comment |
$begingroup$
The dilation of time is only relevant from the perspective of someone far away from the black hole. Close to the black hole time is still progressing forward at what would appear to be a normal rate to someone who is close to the black hole. The movie Interstellar had a great depiction this phenomenon, with the astronauts Copper and Brand on Miller's planet, near the black hole, spending only a few hours, but the astronaut Romilly aging decades as he remained far from the planet. Copper and Brand didn't experience any change in the passage of time, from their perspective.
Matter falling into a black hole would not experience any change in its perspective of time, so would not appear to change speed, other than what would be expected by the gravitational attraction.
answered 3 hours ago
Bob516Bob516
2228
$endgroup$
The dilation of time is only relevant from the perspective of someone far away from the black hole. Close to the black hole time is still progressing forward at what would appear to be a normal rate to someone who is close to the black hole. The movie Interstellar had a great depiction this phenomenon, with the astronauts Copper and Brand on Miller's planet, near the black hole, spending only a few hours, but the astronaut Romilly aging decades as he remained far from the planet. Copper and Brand didn't experience any change in the passage of time, from their perspective.
Matter falling into a black hole would not experience any change in its perspective of time, so would not appear to change speed, other than what would be expected by the gravitational attraction.
answered 3 hours ago
Bob516Bob516
2228
answered 3 hours ago
Bob516Bob516
2228
answered 3 hours ago
Bob516Bob516
2228
answered 3 hours ago
Bob516Bob516
2228
2228
add a comment |
add a comment |
dwstein is a new contributor. Be nice, and check out our Code of Conduct.
dwstein is a new contributor. Be nice, and check out our Code of Conduct.
dwstein is a new contributor. Be nice, and check out our Code of Conduct.
dwstein is a new contributor. Be nice, and check out our Code of Conduct.
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$begingroup$
Additionally to RobJeffries's answer, if you're very interested, familiar with General Relativity and have a bit of time leftover, I can recommend youtube.com/watch?v=BdYtfYkdGDk this video lecture on how black hole physics works. The speed-up and slow-down is discussed there as well.
$endgroup$
– AtmosphericPrisonEscape
1 hour ago