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Gravitational Time Dilation Near Center of Gravity [duplicate]

Stretch your imagination a bit and imagine an almost empty universe with nothing in it but a very, very large asteroid (or an asteroid in our universe but in an almost empty patch so it's not affected ...
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0answers
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What's the smallest height difference over which gravitational time dilation has been experimentally observed?

In a famous experiment, reported in Optical Clocks and Relativity. CW Chou, DB Hume, T Rosenband and DJ Wineland. Science 329 no. 5999 pp. 1630-1633 (2010); NIST eprint. and nicely described in ...
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2answers
182 views

How do we age if we tunneled to Earth's core?

Scenario Suppose there exists an advanced technology that can hypothetically transport living humans to study the center of the Earth, as they goes deeper underground most of the Earth's mass would ...
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1answer
44 views

Time relativity / paradox [duplicate]

After watching the movie Interstellar, the theory of time relativity / paradox really mind-boggles me. If it is true that gravity controls everything even to the extent of time, then it might as well ...
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1answer
99 views

What are the photon/electron consequences of matter in a gravitational time dilation?

So I saw Interstellar, and it got me thinking. I won't even mention all the plot holes, but I wanted to ask about a planet orbiting a black hole. I always thought you had to travel near the speed of ...
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1answer
48 views

Since the earth is moving through space, do we experience time dilation?

What I mean is, the earth orbits around the sun at around 30km/s, while I understand that this isn't a very high velocity does time dilation still occur to say a person who is completely stationary in ...
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2answers
126 views

Can light travel faster?

I'm on Earth. Joel is on a planet orbiting near a black-hole's horizon. Every year on Joel's planet is equivalent to 10000 years on Earth due to the gravity of the BH. The two planets are 10000 ...
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1answer
21 views

Is gravitational time dilation the same for an object at $x$ radii from a black hole no matter what size the black hole is?

Assuming you have two non-rotating black holes. Black hole 1 is 1 meter in radius while black hole 2 is 10 meters in radius. If you are standing 10 meters from black hole 1, would you experience the ...
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1answer
35 views

How does the photon differentiate between events?

As far as I know for a photon that's moving at the speed of light (obviously) time comes to a halt and space contracts to a point, making all travels instant from its perspective. Now this is the part ...
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2answers
100 views

Why are the proper time and the proper length not defined in the same frame of reference?

I've just read this interesting Wikipedia article about time dilation and length contraction in special relativity. . Derivation of time dilation Applying the above postulates, consider the ...
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0answers
41 views

How can matter reach the singularity of a black hole if time stops at the event horizon? [duplicate]

Black holes are said to be composed of two parts: A singularity at the center, where all the mass of the black hole is condensed in a point of zero volume. A black and empty ball delimited by the ...
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3answers
79 views

How does an electromagnetic field oscillate if time does not pass for the speed of light?

As far as I'm aware, traveling at $c$ will prevent time passing due to time dilation. Electromagnetic waves rely upon oscillations to propagate. Since oscillations rely upon the passing of time, how ...
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2answers
59 views

Time Dilation: One observer at rest, two observers in motion

I am currently taking a course in Modern Physics mainly focused on Special Relativity and came up with the following problem: Let $O_1$ be an observer at rest. A second observer $O_2$ is moving to ...
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6answers
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Is it possible to watch the same distant star's supernova event twice?

Usually relativistic time dilation effects require something traveling near the speed of light. But the high speed requirement can be replaced with a high distance requirement instead. Traveling away ...
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1answer
28 views

What is speed relative to in time dilation? [duplicate]

This has always baffled me. There is no absolute speed as I understand(or is there)? Speed is a relationship between two objects. So how can you calculate how much time slows down for an object ...
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1answer
221 views

Would time dilation cause a planet to rotate?

For the sake of the argument lets use a black hole so the time dilation effects are greater and the planet in question is orbiting close enough to have significant TD effects but far enough to not ...
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1answer
42 views

Time and speed - Theory of relativity - 'felt time'

Assuming time is relative according to the objects current speed, means that a clock within a space shuttle which has 30% of light speed is 'ticking' slower than a clock staying on planet earth just ...
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0answers
34 views

The limited Computing Capabilities of Space, Increased quantized info leads to time-dilation?

Are there any approaches to Special and General Relativity using space as a computing medium? With space having a maximum computing capability and time dilation as lag? Could this idea describe the ...
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1answer
65 views

Time dilation as an effect of energy density

Has any relation been observed or postulated to exist between the energy-density (or the surrounding space) of an object and time dilation? i.e. Higher energy density==>Slower rate of time?
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1answer
36 views

Energy variations of cosmic background radiation

Has anyone been able to measure a difference in the energy density of Cosmic Background Radiation in a gravity well compared to zero gravity?
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2answers
77 views

Time dilation due to change in speed

I can't get something strait... Lets use the usual example: A man is flying away from earth on a very fast spaceship. So, His time is now not moving in the same "speed" like earth time but slower. But ...
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1answer
32 views

At what velocity would a body need to travel at to experience noticeable (couple minutes) time distortion?

When a person experiences higher speeds, the light must travel a greater distance to reach the person whom is moving compared to that whom is staying still. Right? So therefore, light takes slightly ...
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1answer
39 views

Can surrounding masses influence the speed of time (excluding the time dilation due to gravity)?

https://www.youtube.com/watch?v=ev9zrt__lec @6:22-7:22 If you removed the middle and front spaceships, will the time of the last spaceship flow differently? As this is what it appears to suggest.
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2answers
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Special relativity thought experiement

Say you see a spaceship moving relative to you. On this ship you see a timer. When a beam of light is emitted from one end of the ship the timer starts. When the light reaches the other end of the ...
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3answers
74 views

Does light itself experience time dilation?

This seems weird for me. Every time I see light, I will think, "Hey, that light travels from the past far away from us!" Correct me if there is misconception.
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1answer
118 views

Could there be a time dilation of 2,000,000x between Earth and other parts of the universe?

Don't ask me why, but you may be able to guess why I would ask such a question. The question is, what kind of conditions would have to be present in a universe in order for billions of years pass in ...
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1answer
278 views

What does v=c in the Lorentz transformation for time tell us?

For the simpler cases as boost in the x-direction, the time dilation formula following the Lorentz transformation for time is $$\Delta t'=\gamma(\Delta t-v\frac{\Delta x}{c^2})$$Now, we observe that ...
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29 views

Relative time difference and the gravitational potential of the geoid

I'm having trouble with something from a problem set on relativity and time. We are given the equation for time elapsed on a clock on the Earth's surface relative to time at the geocenter ...
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0answers
25 views

Time dilation: different clocks [duplicate]

The plane is flying with a speed u=300m/s. How much time Δt′ would have to pass for a passanger on that plane for time difference 1s to occur between the time Δt′ on the plane and the time Δt on the ...
2
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2answers
60 views

Basic Relativistic Question - length measurement

A while ago we did an easy, introductory exercise on length measurement. Back then it seemed pretty straightforward but now when I look at it I have trouble understanding the assumption which led to ...
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2answers
126 views

Lorentz transformation paradox

I got to solve a simple exercise about special relativity when I kinda came to the conclusion it doesn't stroke with my intuition. The homework-problem The problem was about two people Sam and ...
1
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1answer
71 views

Can an observer B move in such a way that his clock will run faster than that of a fixed observer A?

My understanding of Special and General Relativity comes from books which attempt to explain them to non-experts in these fields. Let A and B be observers, which at some time t(0), are together at ...
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1answer
40 views

Relativity and Galaxy Rotation Speed

If time travels slower nearer gravity wells, why can't the galaxy rotation speeds being faster on the outer edges than the inner areas be explained by relativity? What necessitates dark matter?
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2answers
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Why isn't the center of the galaxy “younger” than the outer parts?

I understand that time is relative for all but as I understand it, time flows at a slower rate for objects that are either moving faster or objects that are near larger masses than for those that are ...
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0answers
64 views

Gravitational time dilation in changing curved space time

Imagine a portion of spacetime which is changing its spacetime curvature because of an object with great mass travelling nearby. For instance, before it was flatter, and after the object passes it ...
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1answer
243 views

What is the largest disparity of gravitational time dilation from earth's that life can survive?

In certain theoretical scenario's a human can be in a gravitational field where he would age half as fast as on earth's surface. However, for light to travel half as fast in one direction, we are ...
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0answers
42 views

Do GR and SR have to be considered together to determine time dilation? [duplicate]

In another related question: How to connect Einstein's Special Relativity(SR) with General Relativity(GR)? , John Rennie stated that SR is a subset (or rather can be derived from) GR, but not vice ...
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3answers
203 views

Confusion about proper time in special relativity

I have a problem understanding what proper time really means, well actually, it's the symmetry that confuses me... Suppose for convenience that particle A has a mean life-time of 10 seconds in its own ...
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1answer
69 views

Special Relativity Explanation [duplicate]

I'm in a relatively basic Physics class in university, and was reading the section in my textbook about The Principle of Relativity. It says: Einstein's Theory of Relativity ... added the ...
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0answers
30 views

on what factors time depends physics [duplicate]

On what factors the "Time" depends? In time dilation experiments we use a light clock in which a pulse of light moves up and down between two mirrors. We derive that, for a person in movement, his/her ...
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1answer
35 views

Time difference between two moving inertial frames of reference [closed]

This is a question I am trying to solve: Let S and S' be two inertial frames of reference and S' is moving relative to S at a velocity of 0.6c. When x = x' = 0, t = t' = 0. At t = 2 x 10-7 s, an ...
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3answers
129 views

Does gravitational time dilation affect apparent mass?

Suppose I'm on a highly elliptical orbit around some massive body. As I get closer, I start to experience time dilation due to the object's gravitational field - time starts passing slower for me than ...
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2answers
70 views

Time Dilation Properties

I've read up on time dilation and how gravitational/kinematic time dilation work but I have not received a clear answer on how the two work together. If you are observing something traveling at a ...
2
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1answer
54 views

Measuring time dilation

After watching a certain recent film, I started wondering whether it would be possible to create a watch (or, more likely due to the sizes of the components, a clock) capable of measuring one's time ...
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0answers
35 views

Do charges attractions cause time dilation? [duplicate]

I was pondering whether charges will cause time dilatation? Let me explain more, well we know that gravity causes time-dilatation because of gravitational acceleration which is equal to: $$a = ...
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1answer
102 views

Solving relative velocity without Lorentz transform [closed]

A train with proper length $L$ moves at speed $\frac{5c}{13}$ with respect to the ground. A ball is thrown from the back of the train to the front. The speed of the ball with respect to the ...
2
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0answers
84 views

The relativistic effects of angular velocity

Imagine I have a circular disk in a vacuum. I apply a constant force, so a constant torque on the disk. My first question is: does this disk have a angular velocity speed limit? I believe it does, ...
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1answer
127 views

Time-reversed twin paradox

This started with wondering about the nature of certain physical quantities under time-reversal - chiefly, that acceleration retains its magnitude and direction at a given time regardless of the ...
2
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1answer
128 views

Time dilation simple derivation

In a special theory of relativity we have a phenomenon known as time dilation. There is a simple explanation of this, with a thought experiment with a train and a flash light: We flash a light in a ...
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3answers
356 views

A sees B's clock running slow and B sees A's clock running slow? [duplicate]

This paradox is very common it seems, in which A sees B's clock running slow and B sees A's clock running slow. Here is the question a little more concretely. Let's say B flies by A's spaceship. If ...