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Questions tagged [time-dilation]

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1answer
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Muon decay in muons frame of reference, time muon expects us to record

I have already asked a question regarding this concept but it was flagged as a duplicate. I know this misconception is very common for special relativity but I haven't found a question that talks ...
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0answers
48 views

It seems to be a disproof for time dilation, according to a proof [duplicate]

Let's say the light Ray is emitted in an angle relative to the floor of spacecraft, in which the motion of light Ray relative to earth is a line perpendicular to the horizon. Then the proof in the ...
0
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2answers
74 views

Can time dilation show who's moving?

Imagine a person going in a spacecraft moving away from the Earth, when he return from his journey he notice the time has passed slowly than for the habitants on the Earth. Noting this, we can ...
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1answer
23 views

How much does time-dilation effect our observance of the most massive objects in our solar system?

Disclaimer: I'm kind of a newb, so I apologize if this question is not well formed. Please comment if anything is unclear, and I will do my best to make corrections. Reading this post about time ...
0
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1answer
48 views

Special relativity and time dilation

Im studying Relativity and there is something that my mind really cant proccess right now. That would be the Deformation of time on heavily gravitational bodies. For an example lets take the movie ...
5
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2answers
719 views

Gravitational time dilation compensated by acceleration

I would like to compare the time indicated by two clocks: clock A is located at the top of a mountain, the clock B is in an helicopter flying stationnary at the same altitude than the clock A. Clock ...
-1
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1answer
25 views

Respect to What Time is Calculated in Space

This may be the silly and stupid question but I have read that time appears to move slower near massive objects because the object's gravitational force bends space-time and the phenomenon is called ...
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0answers
40 views

Why doesn't time dilation prevent black holes from growing?

From the point of view of an external observer, matter falling into the black hole is supposed to never cross the event horizon due to time dilation. At the same time, black holes are supposed to ...
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0answers
23 views

Trouble understanding time dilation [duplicate]

I am new to relativity, so I am sorry if this question is stupid. I've been having some trouble understanding time dilation. My problem comprises of a spaceship moving at a very high speed relative to ...
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0answers
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Time dilation explained as gravity / acceleration effect on clock itself? (no spacetime fabric) [duplicate]

Simple: Why can't 'time dilation' be explained as the drag put on any form of clock by gravity /acceleration ? Nothing is unaffected by gravity, including workings of atomic clocks. Why have we ...
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0answers
26 views

Gravitational Time Dilation - What is wrong with this graph? [duplicate]

I am trying to plot the gravitational time dilation as a function of orbital height. But I seem to do something wrong: $$ dt=\frac{\mu s}{d}\left(\sqrt{1 - \frac{2GM}{(r_E+x)c^2}}-\sqrt{1 - \frac{2GM}{...
0
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1answer
48 views

Deriving Doppler effect in observer's frame

I am attempting to find the Doppler factor from the frame of the observer. In the frame of the observer, the source is moving at velocity $v$ towards the observer. Since the source emits at time ...
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0answers
41 views

Gravitational time dilation derivation

One way of deriving gravitational time dilation is to imagine an observer in free fall in some gravitational field passing by two observers stationary in that field. Because inertial observer passes ...
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0answers
54 views

Time Dilation and Particle Decay

I am teaching myself astronomy and I'm working on a basic problem regarding time dilation around black holes. The question is basically this: if a neutron were ejected from a nucleus at a distance of ...
1
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3answers
62 views

Method to observe clocks on spaceships moving near $c$?

I have read the explanation for clocks slowing down on a spaceship moving relative to a stationary observer -- something like a beam of light between two mirrors taking longer for the observer to ...
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0answers
22 views

What is the relationship between time dilation and gravitational time dilation? [duplicate]

This may be a stupid question as I have no background in physics but I'm curious: We know time stops when approaching the speed of light and also as object approaches the event horizon of a black ...
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0answers
67 views

How can we justify time dilation if we look through an spyglass at Einstein's light clock?

Assume that a space shuttle travels in a circular path having a radius $r_s$ at a tangential speed $v_s$ - a considerable fraction of the speed of light. There is a light clock inside the shuttle ...
2
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2answers
81 views

Is there a connection between the energy distribution and time dilation?

Can anyone please help me understand what is descibed bellow? Scenario 1. We have a pair of atomic clocks. Let's call them clock A and clock B. We switch both of them on at the same time. Clock A ...
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0answers
46 views

Apparent FTL speeds seen by observer

MY guestion is if I was in a ship orbiting a black hole (not very close to the event horizon) I am orbiting pretty far and I am experiencing that my time is slowing down realitive to people on earth. ...
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0answers
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How to calculate mass from time dilation and radius?

I'm new to this site and I'm been searching the internet all over for this solution. I'm looking for an equation, that if given the time dilation at the surface of an object and its radius, it will ...
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1answer
36 views

What do you think of this conceptualization of the universe and time dilation? [closed]

So the universe is ever-expanding. It's been expanding in all directions since the Big Bang, like how a sponge expands when you give it water. The universe is made of a fabric known as space-time. The ...
0
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0answers
23 views

Should we need to consider time dilation effect when travel in a very fast rocket? [duplicate]

How long does it take for a rocket to reach a planet 10 light years away if the rocket's speed is just near the light speed? If the speed is 1 c, the folks will answer it will take 10 year to travel ...
3
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1answer
50 views

Photon emittance of objects under the effect of time dilation

Light that is emitted from objects under the effect of time dilation (from out point of view) is redshifted that much is clear. However I am interested if another effect occurs that I never seem to be ...
2
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2answers
97 views

Time dilation, and curvature of space caused by two black holes of unequal masses

If you were to try to find the time dilation in a region of space near a black hole you would use the equation $$t_r=\sqrt{1-\frac{2GM}{rc^2}}$$ Would the time dilation from two black holes be this? ...
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3answers
59 views

If things travel at different time rates due to relativity wouldn't one of them disappear from my perspective? [closed]

If I travel to a 3d location where Einstein was known to have existed at some other time, I do not expect to see him, because his 4d location is different! Why then can I send a clock around a black ...
3
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1answer
101 views

Interpreting Time in Bells Spaceship Paradox

I’ve seen a lot of arguing about Bells Spaceship Paradox, so it appears to confuse even some physicists. In Bells Spaceship Paradox, two ships begin simultaneously accelerating at a constant rate ...
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1answer
77 views

Problem on derivation of time dilation

In my lecture notes, there are two frames S and S'. The prime frame moves with uniform velocity with respect to the unprimed frame. In this frame, she derives the time dilation equation in the ...
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4answers
111 views

How do we determine who is the “observer” when calculating time dilation? [duplicate]

I was reading about time dilation and I thought of a question. I really think that I am just misunderstanding something, so please bare with the question. But, I would appreciate if somebody could ...
0
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4answers
84 views

When photons are moving at the speed of light, how come they change in position?

From what i know, photons are moving at the speed of light and that means the time that photons are experiencing is zero, but here is the thing... If the time is zero how can they travel astronomical ...
0
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1answer
36 views

Trying to understand velocity addition and time dilation [duplicate]

I'm familiar with Einstein's formulae $V=\frac{u+v}{1+ \frac{uv}{c^2}}$ and $\Delta t'=\frac{\Delta t}{\sqrt{1-\frac{v^2}{c^2}}}$, the former being velocity addition and the latter being time dilation....
2
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0answers
74 views

Problem in Special Relativity [closed]

"A space probe is sent to the vicinity of star Capella, which is $D = 42.2 \ light \ years $ from earth. The probe travels with a speed of 0.9930c. An astronaut recruit on board is 19 years old when ...
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2answers
62 views

The Necessity of Light for the Synchronization of Clocks in Special Relativity

In Einstein's paper, "On the Electrodynamics of Moving Bodies" light is used to synchronize the clocks of two different points in space. Thus if a frame S' is moving relative to frame S, an observer ...
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0answers
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Twin paradox with one twin in orbit, one in radial free-fall

Many questions on Physics SE relate to the twin paradox, but I did not find any that ask this specific question. Suppose that object A is in a circular orbit around a spherically symmetric, non-...
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2answers
104 views

What does it actually mean to say that time “speeds up” or “slows down”?

I was thinking lately about relativistic time dilation and time passing differently on other planets (which both, eventually turned out to be caused by the same principle). Now, quite naturally (as ...
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0answers
28 views

Time dilation of accelerating object vs caught by gravity well

Suppose an object got caught by the immerse gravitational force but at the same time it has zero net force acting on it like suspending above the surface of a planet, not siting on the surface where ...
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1answer
73 views

Is speed of light is the only way to measure time [closed]

After reading up on special relativity, I understood that because of Einstein's postulates -the speed of light in free space is a universal constant Everytime we measure time for an event, directly ...
0
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1answer
36 views

How can time dilation occur for one person but not another? [duplicate]

I have heard of the thought experiment where someone fly off in spaceships and come back younger than their twin on earth. But a fundamental idea behind general relativity was that motion can only be ...
0
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0answers
53 views

Why am I not getting the right values for the time it takes a spaceship to get to 0.9c? [duplicate]

I'm attempting this problem: Rocket undergoes constant acceleration from rest until it reaches a speed of 0.9c. The astronaut in the rocket feels a constant "induced gravity" of 1g. How long does it ...
0
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0answers
34 views

How can our universe have black holes? [duplicate]

Assuming that we were never inside a blackhole at any point in the history of the universe, how can blackholes exist against Gravitational time dilation? For any point in space time in the known ...
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3answers
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Speed vs Velocity of light in Light clock thought experiment

A related question has been asked multiple times (like here, here and here). But none of those answers are clearing my doubt. In fact they're furthering my confusion. My specific doubt is regarding ...
2
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3answers
105 views

A twisted triple paradox

As far as I know when a person travels with some velocity relative to other person time runs slower to him relative to the other person (Because the velocity of light is constant in all frame of ...
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0answers
17 views

How time dilated is the average particle relative to the big bang? [duplicate]

Particles created during the being bang have experienced time dilation by means of gravitation and general acceleration for the past 13.8 billion years. On average, how time dilated is the average ...
2
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0answers
92 views

Can someone travelling close to the speed of light witness the end of the universe? [closed]

I have read that objects with non-zero rest mass cannot attain light speed $c$. But for the sake of this question let us assume that Mr. X can get as close to $c$ as he wants. So this means that an ...
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2answers
65 views

Time Dilation and Length contraction - thought experiment

Sorry if this is obvious, but I've searched and cannot find this answered. taking a minor change to the light clock experiment on a traveling spaceship. putting the clock in the horizontal position,...
2
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2answers
111 views

Do planets experience time dilation as they orbit the sun and if so what effect would this have on their orbit

Do the planets experience time dilation as they increase / decrease speed around the sun and are experiencing higher and lower gravitational forces as they move from a closer position i.e. the ...
0
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1answer
118 views

Is time passing really differs on other planets/in interstellar? [duplicate]

I am aware of the idea of time dilation (which I, by the way, asked another question about) on speeds, that get close to the speed of light. Though, I wonder what other (if any) forces and laws affect ...
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4answers
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How close should you get to speed of light, in order for time to be dilated?

Recently I was watching Carl Sagan's Cosmos: A Personal Voyage. In episode 8 ("Journeys in Space and Time") there is a scene presenting the idea of time dilation, due to traveling close to the speed ...
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1answer
59 views

Time dilation caused by gravity and special relativistic velocity [closed]

I am working on an exercise for my Relativity class. The exercise is: Two atomic clocks are transported in two aeroplanes once around the Earth in either eastern or western direction. For ...
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0answers
39 views

Quantum wave function evolution and time dilation [closed]

We know that spin state evolves with time...but in non relativistic QM time dilation is not accounted ...so in Dirac equation does evolution of spin state with time depend on speed...i.e does time ...
2
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3answers
72 views

Can length contraction help the moving observer reach a star system 'faster'? [duplicate]

Would an observer moving with close to the speed of light ($\sim 99\%$) towards a star system that's $20$ light years away perceive the distance as being less than $20$ light-years? If yes, how much ...