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-3
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0answers
28 views

Difference in time for clock in attic vs clock in cellar [on hold]

This question is regarding relativity: Two clocks are stationed in a house, one in the cellar and one it the attic. Which one of the following statements is true? A : The clocks tick at the ...
0
votes
1answer
56 views

Why do we not apply length contraction when finding out the time taken for objects moving at relativistic speeds?

I was going over a question on my own, then I took a brief look at the solution...it's basically about A rocket has a proper length of 250 m and travels at a speed v = 0.950c relative to the Earth. ...
-1
votes
0answers
50 views

Relativity of time in regard to speed of light [on hold]

Someone stated that if you go on a train for 1 year going 99.999999999% the speed of light 233 year would have passed to those outside the train due to time dilation. So what speed do we perceive time ...
1
vote
0answers
18 views

Time Dilation for a photon [duplicate]

Does a photon experience any time. Since a photon is massless and hence travels at (c) then it should suffer infinite time dilation, and hence shouldn't experience no time?
0
votes
0answers
25 views

In the GPS system, does the satellite clock see the earthbound clock moving slower, due to relativity?

In the GPS system, does the satellite clock see the earthbound clock moving slower, due to relativity? Suppose that a GPS satellite was moving at .9c. Would it see the earthbound clock running ...
0
votes
1answer
39 views

Funny Time Dilation Relation

Today I was curiously calculating/comparing the times of moving observers and the time recorded by a corresponding stationary observer using Einstein's time dilation equation as detailed in Special ...
-1
votes
2answers
44 views

can time dilation be used to determine if an object is moving

I know that movement is only relative to another object, but as you move faster you also experience time dilation, correct? So if one body is moving faster then it should have a dilation of time, ...
0
votes
1answer
13 views

Would Gravitational Time Dilation still apply between two gravitational sources?

As explained on this Wikipedia page, when an object is experiencing strong gravitational forces, time passes slower for it. If, in theory, you had two objects exerting the same amount of gravitational ...
-1
votes
1answer
48 views

Relation between two clocks in two different Reference frames [closed]

I'm beginning to study Special Relativity and I'm a bit confused with Lorentz transformations. Here's my doubt. Imagine two reference frames, $S$ and $S'$, and suppose $S'$ to be moving at a velocity ...
1
vote
1answer
77 views

How is time dilation consistent between both observer?

There is a special variant of time dilation paradox bugs me. Imagine there are 2 small spaceships moving toward each other in constant speed. Each ship has an observer on-board. According to both ...
1
vote
2answers
29 views

Why do relativistic wormholes have to be brought together to make a “time machine”?

In "From wormhole to time machine: Comments on Hawking’s Chronology Protection Conjecture" by Matt Visser (http://arxiv.org/abs/hep-th/9202090), he summarizes how "time machines" may be created from ...
5
votes
4answers
96 views

Would time speed up near a large body of negative mass relative to observers in micro gravity?

Time tends to slow down near objects with large amounts of positive mass relative to observers in micro gravity. Considering that negative mass is the opposite of normal mass and would time tend to ...
1
vote
1answer
48 views

How does time dilation occur due to velocity and gravity [duplicate]

I am trying to understand and clarify the way time dilation occurs due to general and special relativity and for which reason. In the case where an object is approaching a planet in free-fall how does ...
1
vote
1answer
33 views

Is Snell's law a product of Gravitational Time Dilation?

Due to the proximity of atomic structures in a solid liquid or gas, does the gravity of these atoms warp time enough to cause light to move slower from the perspective of an outside observer?
0
votes
0answers
30 views

Why doesn't time dilation resolve entanglement

I'm a layperson who has read bits about relativity and quantum mechanics over the years, so this is a naive question, but I can't see where My reasoning fails... Photons travel at the speed of light, ...
0
votes
0answers
16 views

Simple Question About Repulsive Potential Field Time Dilation

A space-time with a point mass gravitational potential given by $\Phi(r)$ has a metric described by, $$ds^2=-\left(1+\cfrac{2 \cdot \Phi(r)}{c^2} \right) \cdot c^2 \cdot dt^2+\left(1-\cfrac{2 \cdot ...
0
votes
1answer
42 views

Time-dependent time dilation for circular orbits around a Schwarzschild black hole?

Take two clocks, one in a circular orbit around a Schwarzschild black hole and another with a distant observer. The time dilation factor between the two clocks is said (at ...
0
votes
2answers
79 views

Are gravitational force and gravitational time dilation proportional?

Particles in gravitational fields are subject to gravitational time dilation. The closer a particle is near a gravitational source, the slower is running its clock. I would like to know more about the ...
0
votes
0answers
22 views

does falling towards blackhole make universe move faster? [duplicate]

If you fall into a blackhole would you begin to see the events in universe happening faster and faster as you move towards the hole? Also if you survive the fall through the event horizon as seen ...
4
votes
0answers
35 views

Radiative equilibrium in orbit of a black hole

According to Life under a black sun, Miller's planet from Interstellar, with a time dilation factor of 60,000, should be heated to around 890C by blue-shifted cosmic background radiation. How they ...
-1
votes
0answers
33 views

Is there a direct relation between gravitation and gravitational time dilation? [duplicate]

The following calculation seems to show that gravitational time dilation is not only due to gravitation, but that there is a close relation between both of them: Gravitational time dilation seems to ...
1
vote
4answers
223 views

Rapid acceleration does what to inertial frame clocks?

I'm 10 light years from Earth and see Earth's clock/calendar reading 2000, including light travel time. In other words, I assume it's 2010 on Earth, but what I actually see is the year 2000 due to ...
0
votes
0answers
36 views

Is there a relation between time dilation and (relativistic) mass increase?

I noticed that what once called relativistic mass increase and now is called energy increase is ruled by the same formula the Lorenz factor of time dilation? The formula is too particular to suggest ...
-4
votes
0answers
33 views

What happens if 2 objects were thrown against each other at lightspeed? [duplicate]

What happens if 2 objects were thrown against each other at light-speed (or near of it)? Can we say that by the point of view of the 1st object, the 2st object has a 2c speed ? what happens to the ...
0
votes
1answer
63 views

how long will take for an astronal travel in near lightspeed in his point of view

I always had a question about relativity. Suppose an astronaut in orbit Saturn just must reach earth fast as possible. Your ship can travel at any speed between 0 and the speed of light. the distance ...
0
votes
1answer
161 views

Does Inertial time dilation demonstrate that Time is not a dimension? [duplicate]

If time is a dimension and 'now' simply an expression of your position with respect to that dimension, the progress of any object along that dimension should remain in step with all other objects. By ...
1
vote
0answers
15 views

A Question about Time Dilation and different observers [duplicate]

This is a question about time dilation and different observers. Say you had two observers. One on earth and the other one traveling around 20% of the speed of light. The observer on earth will age ...
0
votes
2answers
33 views

Time dilation when an object moves [duplicate]

Why does time dilation happens when the object moves, is it just because the physical processes, in the moving objects, happens slower? (this video suggests this: https://youtu.be/Ci4L6myFFng?t=224) ...
0
votes
1answer
44 views

3 points in space, relative motion, and the speed of light

I'm new to thinking about relativity, as well as phenomena related to the speed of light, time dilation, length contraction, simultaneity, etc. I am pondering a paradox. Assumptions: Motion is ...
0
votes
1answer
47 views

Spacetime Mercury vs Earth

What is the time dilatation of the planet Mercury compared to Earth? Can a person survive on the dark side of Mercury in the In the L2 position to Mercury and the Sun?
0
votes
0answers
30 views

What would you see standing on black hole just above the event horizon ? Will you look through past and future of the universe? [duplicate]

I am trying to imagine view from my house window if it was built on the black hole;) .... Of course I am joking. If time near event horizon slows down with respect to rest of the universe. I could ...
-8
votes
1answer
78 views

Explaining The Quantum Mechanics Weirdness [closed]

Academic replies only; I would like feedback on this, so yes i am asking you to poke holes in it, it is about explaining the time weirdness of quantum mechanics and how particles behave. When the ...
0
votes
0answers
40 views

complete layman trying to understand time relativity [duplicate]

I am trying to understand intuitively why time slows down as speed increases. I have watched many pseudo-documentaries explaining the concept, but I cannot get at the core of the explanation. The ...
1
vote
1answer
39 views

Near light speed space travel to more than one star and back to earth?

I'm afraid this one is kind of a yes or no question, because I think I would get lost in the discussion of metrics, etal. As a layman, I get that if you travel fast enough (by accelerating and ...
0
votes
2answers
67 views

Time Dilation diagram on wikipedia

The wikipedia article on Time Dilation (http://en.wikipedia.org/wiki/Time_dilation) has an explanation involving the following two diagrams: I have some problems with these diagrams. In the second ...
40
votes
5answers
5k views

What is time dilation really?

Please will someone explain what time dilation really is and how it occurs. There are lots of questions and answers going into how to calculate time dilation, but none that give an intuitive feel for ...
0
votes
2answers
78 views
-1
votes
3answers
86 views

How time dilation happens by velocity?

i got many explanation and proving that relative velocity causes time dilation. Einstein's moving light experiment proves it. but that is a clock works with light detector. as detecting the light gets ...
0
votes
1answer
29 views

Time dilation in a sphere of gas of constant density

If you have a sphere of gas of constant density, would something in the center of this gas experience time dilation relative to someone in empty space (not just someone outside the gas, but someone in ...
0
votes
1answer
58 views

Does time and time dilation exist in a black hole?

Since being near stronger gravitational fields causes time dilation, can this be generalized to the region beyond the event horizon? i.e , is it meaningful to say that someone outside the black hole ...
1
vote
0answers
35 views

From which reference frame is the time dilation factor measured?

I do not know much physics so please try to answer as simply as possible. I am probably confused but I recently learned that in Special Relativity (you can tell that I don't know much physics), the ...
5
votes
1answer
93 views

Two places having same gravitational acceleration - Do they also have same curvature of space time?

If there are two places (possibly on/above two different planets) having same gravitational acceleration (g), would it imply that the two places have same extent of space time curvature and will have ...
-1
votes
1answer
153 views

Time dilation confusion? [duplicate]

If I understand the theory correctly, time dilation causes a moving clock to tick slower than a stationary clock. If clock A is moving relative to clock B, then clock A ticks slower. However, ...
1
vote
4answers
64 views

Time dilation and Lorentz transformation

I have trouble understanding the Lorentz transformation to proof the dilation of time. If I use: $$dt ^{'} = \frac{dt}{\sqrt{(1-(v^2/c^2))}}$$ Understanding that $S^{'}$ is the moving frame of ...
1
vote
4answers
119 views

Is there anything we are aware of that can't be slowed by time dilation?

While thinking about the ambitions of this post: Can radioactivity be slowed through time dilation? I was asking myself, is there even anything that is dependent on time and can't be slowed through ...
1
vote
2answers
87 views

Is Time Dilation in GR Simply a Consequence of Curved Space?

My understanding of time dilation in General Relativity is that it is the consequence of particles traveling at the speed of causality following longer, curved paths. Since it takes longer for two ...
43
votes
3answers
7k views

Can radioactivity be slowed through time dilation?

Can radioactivity be slowed using the effect of time dilation? If you put cesium, tritium or uranium in a cyclotron at relativisitic speeds, do their half lives become longer in our frame? Could ...
2
votes
1answer
62 views

Gravitational waves induce changes in the $h_{00}$ (time) component of the metric?

I'm rather stumped by a subtle point regarding metric perturbations of GW. I'm well aware the GW are able to produce changes in the flat space metric, They are transverse and have planes of ...
0
votes
1answer
27 views

How is light used to measure the change in time caused by gravity?

Is the following analogy correct, if not- what changes are necessary to correct it? Let's consider a guy riding on a photon with a clock, and every time his clock ticks he paints a dot. Let's also ...
0
votes
2answers
56 views

Why is the SR behavior of mass and a clock different? [closed]

A frame contains a mass and a clock, an an adjacent frame contains an identical mass and clock. One frame travels and returns. The special relativity equations for mass and time are identical in ...