All Questions
Tagged with general-relativity time-dilation
429
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Twin paradox - how much energy does it take to travel to the future? [closed]
In the usual twin paradox in Minkowski space, we have twins Alice and Bob. Alice stays at home. Meanwhile, Bob visits a distant planet and returns. On return, Bob has aged less than Alice. So, in a ...
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Time Dilation And Comparing Inertial And Non Inertial Reference Frames
Can we calculate the total observed time dilation on a spaceship and a planet by combining the planet's relativistic spin velocity and the spaceship's approach or recession velocity from the planet it ...
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1
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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 ...
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Question regarding Time dilation of satellites
My name is Shaun Kant.
I was wondering about why the satellite's time is faster with respect to Earth's time. PBS space time mentions that fact. However, Wikipedia mentions that at the ISS (...
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What could a year long journey look like, while traveling near the speed of light, through the lens of that telescope?
Hypothetically speaking if you had a satellite going near the speed of light in a straight line towards an exoplanet light years away and that satellite had a telescope pointed at the surface of an ...
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Is it possible for things to fall past the event horizon? [duplicate]
Everything I can find says that time dilation approaches infinity at the event horizon of a black hole. Black holes evaporate over a finite amount of time. Wouldn't this imply that somebody falling ...
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Is there really no way to know if you are accelerating or you are in gravitational field? [duplicate]
So any gravitational field will have a gradient, no? But an accelerating object does not experience any gradient of force. So you should be able to tell if you are in gravity or accelerating by ...
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How massive should a body be in order to significantly affect the passage of time?
I have read that the effects of time dilation due to relative motion become noticeable after a speed of about 10% of the speed of light.
The Wikipedia article on time dilation says this:
It is only ...
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GENERAL RELATIVITY: gravitational time dilation outside 2 bodies [closed]
I know that gravitational time dilation near a single body is:
$$T_2=T_1\sqrt{1-\frac{2GM}{rc^2}} $$
Can you give gravitational time dilation formula when in proximity to multiple bodies?
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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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Why don't we put satellites into an orbit where there is (almost) no time dilation/contraction compared to Earth's surface?
Consider:
On this image, if I understand correctly, the time dilation diagram is shown depending on the height for circular orbits. First in low orbit, time slows down relative to the surface due to ...
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Why does time flow more slowly on the ground than on a mountain? [duplicate]
I'm reading the book The Order of Time by 'Carlo Rovelli', which says that time flows more slowly on the ground than on a mountain. It also says that the presence of matter changes how time flows, and ...
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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 ...
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Special relativity in orbit
I am writing something for school where I need to calculate the time dilation difference between Earth and Mars. First I calculated the difference from the gravity of the planets itself + that of the ...
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How to sync up different timelines and real events in general relativity? [closed]
Imagine this scenario:
Mike lives on a massive planet, so massive he experiences time going slowly.
Le petit prince lives on a small planet ( not much time dilation )
After millions of years (making ...
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