All Questions
61
questions
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When it comes to getting closer to the Schwarzschild radius, how is discrete a limit?
From Keeton (2014) in Principles of Astrophysics: Using Gravity and Stellar Physics to Explore the Cosmos, Gravitational time dilation near a large, slowly rotating, nearly spherical body, such as the ...
4
votes
2
answers
627
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GR contribution to time dilation when both clocks are falling freely
When reading simplified explanations of time dilation experienced by satellites, such as those used for the GPS and other satellite navigation systems, the time dilation is often presented as having ...
0
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3
answers
124
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Relativity and variable time - there is an alternate formulation where time is always linear. Has it been studied?
Lorentz, Einstein et. al. assume time is the variable which changes in a gravity well or as speed approaches $c$. That's the commonly accepted model.
For nearly 50 years I've wondered if anyone else ...
- 19
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59
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Time dilatation of a free falling observer [duplicate]
I have two questions about time dilation near a black hole.
(I question) The relation $d\tau^2 = (1-\frac{r_s}{r}) dt^2$ between the proper time $d\tau$ of an observer near a B.H. and the time dt ...
- 21
3
votes
4
answers
835
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Gravitational Time Dilation and the Apparent Speed of Light
It has been proven that time far away from Earth is faster than time on the surface of Earth, due to gravitational time dilation. (GPS satellites take gravitational time dilation to account.)
Would ...
- 141
1
vote
1
answer
157
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What are the effects on a stationary observer at a specific distance from a Kerr Black Hole?
A Kerr Black Hole (BH) is a spinning BH. There is an Event Horizon (EH) which is
$$r_H^\pm =\frac{r_{S} \pm \sqrt{r_{S}^2 - 4a^2}}{2},$$
where $a = \frac{J}{Mc}$ and $r_{S}$ is the Schwarzschild ...
- 123
4
votes
3
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487
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Effects of acceleration and gravity on proper time
Let's consider the effects of gravity and acceleration on proper time of an observer (yes, I want to know how the equivalence principle works).
First situation: a spaceship with rocket engine stays ...
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-3
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1
answer
99
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Would time dilation increase the distance between objects? [closed]
Two objects are moving towards a gravity well. They are at $x$ distance from each other and moving at a fixed speed. The gravity well is massive enough for the objects to experience significant time ...
- 141
8
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7
answers
4k
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Why don't two accelerated clocks behave like two clocks in a gravitational field?
If we immerse two clocks in a gravitational field at different altitudes (with the approximation that both heights share the same g for equivalence to be true), the falling and Schwarzschild observers ...
- 97
12
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4
answers
2k
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How can I calculate gravitational time dilation between two planets? [duplicate]
I am writing a school paper and chose to do it about gravitational time dilation. I wanted to calculate the time that passed on Mars when 1000 years on Earth went by. (probably a tiny difference). I ...
- 131
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2k
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Could a civilisation use “inverse time dilation” to live longer?
If an observer were to live near a black hole of sufficient mass, half an hour could elapse for them, but the outside universe could progress hundreds of years. This is due to time dilation.
We know ...
- 179
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3
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499
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Where in the universe does time pass fastest relative to time on earth?
It is my understanding that time essentially moves slower in higher gravitational fields relative to time on earth. Conversely, in lower gravitational fields, time passes faster relative to earth. Is ...
-3
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3
answers
454
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Does time really slow near the speed of light or does it only seem that way to an outside observer? [duplicate]
I was lying awake last night struggling to sleep as one does, thinking about time and Einstein's concepts of relativity and having some fun with thought experiments similar to the one Einstein ...
0
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67
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What does and observer inside of a collapsing shell observe?
What does and observer inside of a collapsing shell observe?
Lets say we have a shell of matter collapsing to a black hole.
What would observers near the center see? How would the rest of the universe ...
- 2,908
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4
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294
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Time slows down with speed compared to what reference point?
So as far as I understand time dilation it means that time slows down as an object approaches lightspeed. This is an issue even with for example satellites around earth compared to people on earth (...
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