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What creates the physical difference in ageing when travelling close to the speed of light? [duplicate]

I probably have a fundamental misunderstanding, so correct me if I'm wrong. When travelling close to the speed of light, movers experience time dilation, which is what results in the phenomenon of ...
2
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4answers
151 views

Communication near a black hole

One ship is in a stable orbit outside of the event horizon of a very large black hole so that there is significant time dilation. Another ship is in its own orbit around the same black hole, but at a ...
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3answers
76 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 ...
2
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2answers
89 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
54 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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4answers
127 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 ...
2
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0answers
89 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 ...
6
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1answer
150 views

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-...
2
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2answers
120 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
41 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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2answers
45 views

How to calculate distance of earth when observer in space ship which travel with speed of light

Suppose we have two observer one is on earth and other is in space ship. If we launch the space craft and a light ray at the same time from earth, after 1 minute, what will be total distance travelled ...
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2answers
86 views

If we filmed what happens on an extremely time dilated planet in realtime

Say there was a planet that experienced insane time dilation due to orbiting a black hole, say 1hr on there is 7 years on Earth (something like that), and that it was close enough to Earth for light ...
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2answers
70 views

Does the position in universe of a person not matter regarding death?

I might be completely wrong, but watching a documentary about time, the Einstein theory of relativity came up. From their explanation, time "slows down" depending where you are in the universe. I ...
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1answer
76 views

Shortening of distances in Relativity Theory

I am studying relativity theory and I have understood why distances become shorter from the perspective of someone who is travelling close to the speed of light. However, later on I read that the ...
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1answer
49 views

Does an object falling into a black hole appear to become flat for an outside observer?

In special relativity when an object moves close to the speed of light it will appear redshifted due to time dilation. In addition the object will also appear to be length contracted. But what about ...
1
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2answers
107 views

Wormholes and Time Machines

According this paper: Morris, Michael S. and Thorne, Kip S. and Yurtsever, Ulvi (1988) Wormholes, time machines, and the weak energy condition. Physical Review Letters, 61 (13). pp. 1446-1449. ...
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2answers
113 views

Mistake in simple calculation in special relativity [closed]

I am just learning a little bit of special relativity on my own and am obviously still quite confused. I would appreciate it if someone could point out the error in the following calculation: Let A ...
1
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1answer
499 views

Does one age quicker at higher altitudes?

See title: Does one age quicker at higher altitudes? A few years ago I heard that you would age slightly faster (or slower) at higher altitudes. Is this true? What is the theory or evidence for ...
5
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4answers
881 views

How can a mechanical clock tick slower due to time dilation?

I was about to watch Interstellar for the third time when I decided to do some research on its phenomena. Time dilation is the one that struck me most. I have read and read about it and understand -- ...
2
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2answers
721 views

Determining the rest frame

Sorry if this has been asked before in some way, I did try looking through the special relativity tag and didn't really see a good answer to my question. I am having trouble determining which frame ...
-4
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4answers
362 views

How Lorentz transformation is connected to reality and physics?

I don't understand whats the meaning of Lorentz transformation in Special relativity. In physics, the Lorentz transformations (or transformation) are coordinate transformations between two ...
82
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8answers
9k views

How can time dilation be symmetric?

Suppose we have two twins travelling away from each other, each twin moving at some speed $v$: Twin $A$ observes twin $B$’s time to be dilated so his clock runs faster than twin $B$’s clock. But twin ...
0
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1answer
67 views

Time travel (Velocity and Mass)

I learned that if I move on a high velocity, if my watch shows 12:00 and a my home clock shows 12:00 before the trip, when I come back, my watch will be like 12:05 while the clock will be 12:10. I ...
1
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5answers
166 views

Two objects are thrown into a black hole. The first crosses the event horizon at time's end, so when does the second one cross?

An observer throws an object towards a black hole, and then an arbitrary amount of time later, throws a second object towards the black hole. Disregarding Hawking radiation and assuming the Black Hole ...
4
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3answers
218 views

Does Minkowski diagram show that time goes faster in “moving” frame of reference?

I have a question re the diagram that appears at: http://www1.phys.vt.edu/~takeuchi/relativity/notes/section12.html The diagram purports to show that the observer in each frame of reference will ...
-2
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1answer
63 views

How looks a wheel browsing 299000km in 1 second from its own frame?

Imagine a wheel with a 299km perimeter turning at 1000 round per second going 299000km (the speed of the wheel is 299000km/s relative to the starting frame). How does it look in the frame of a pilot ...
2
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2answers
340 views

Special relativity and spinning tires

I apologize for the subsequent headache. There is a person who claims quite adamantly that Einstein is wrong, using the following reasoning: A clock on a train slows down the faster the train moves....
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1answer
383 views

Why is the Lorentz transformation's time transformation not just the time dilation?

In Taylor's Classical Mechanics text, he derives the Lorentz transformation from length contraction which, in turn, uses time dilation. But doesn't the use of length contraction necessitate that the ...
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1answer
123 views

How does time transform in wormholes?

The light from a star 100 light years away takes 100 years to reach Earth so we see remote star as it was 100 years ago. In the same way, we would see Earth 100 years in the past if we were on the ...
-12
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1answer
563 views

Time goes slower the faster you go. What happens to time if you go too SLOW? [closed]

Time dilation is clear about what happens when you go faster than an earth observer, and about what happens when you travel at c. But earth is also moving, and thus we humans are not at the slowest ...
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0answers
35 views

Does time dilation make travelling close to the speed of light redundant? [duplicate]

I find time dilation confusing so I'm not sure if it is a relevant factor. Lets say you have a spaceship. There's no such thing as faster than light travel, but you do have inertial dampener ...
2
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1answer
102 views

Time dilation for non-physicists

Apologies in advance, as I'm not a physicist, and may use terms incorrectly. In the movie Interstellar, the planet Miller has a time dilation of one hour to seven Earth years. This has brought up ...
19
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3answers
3k views

Energy Conservation Dilemma

Assume that a man is travelling in a space ship at a certain relativistic speed with respect to a man at rest at some point in space, such that 3 minutes in the ship is equal to 5 minutes for the ...
0
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1answer
307 views

How and why time stops inside a black hole?

I have recently learned that black holes are dead stars, who are collapsed, and attracted other objects towards it and this process results in a very very large gravity. So light is also unable to ...
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0answers
18 views

An experimentation on time dilation [duplicate]

In the video https://www.youtube.com/watch?v=ev9zrt__lec from 03:00 to 05:00 I hope that both the clocks would read the same equal amount ,say,1 revolution, in measuring the time elapsed for the ...
1
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2answers
65 views

Traveling close to the speed of light, would a person (or anything else) have a longer existence or would the existence be passing in slow motion?

If something, let's say, an electron or a person, travels at some speed close to the speed of light, time would slow down, right? But would it be passing in slow motion or would it have a bigger ...
0
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1answer
65 views

Given Einstein's Theory of General Relativity, would a sample of plants grow to bloom quicker in space than on Earth?

I watched a program the other day on Einstein's General Relativity. It was fascinating. As I understand it GR is the best model of the (large) Universe. The program stated that time literally passes ...
1
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3answers
411 views

Lorentz Transformation in Different Reference Frames

TO ALL: Thanks to the help of many dedicated forum members, I have learned that this problem can be explained by understanding Minkowski diagrams. Here is a consolidated list of helpful links: https://...
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1answer
120 views

Observers at the speed of light [duplicate]

Just a quick question to help me see if my reasoning is right. The speed of light is constant from all frames of reference. So does this mean that an observer travelling at the speed and taking into ...
1
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0answers
75 views

Time dilation on moving clocks [closed]

Three observers are standing on Earth's surface with identical indestructible clocks. One observer tosses his clock up such that it returns to its original height after a time T by that clock. The ...
0
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4answers
522 views

How does gravity slow a clock at a distance?

If you have two identical clocks that are synchronized and then you move one significantly closer to a black hole but still far from the black hole, the closer clock will mark time slower than the ...
14
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2answers
3k views

Understanding Time Dilation at the Event Horizon

I was recently reading about the event horizon of black holes and came across the fact that, to a "stationary" observer, it takes forever for someone to fall into a black hole. The sources claim that ...
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1answer
215 views

If the faster I go, the slower time becomes for me, then does that mean the slower I go the faster time becomes?

Disclaimer - I’m not a trained physicist. I just have an interest in the subject so this question is probably going to come across really confusing but I’m trying my hardest to explain. So firstly, ...
1
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2answers
479 views

Will moving observer see time dilation?

Please look at this animation. The green dots and red dots in the animation represent spaceships. The ships of the green fleet have no velocity relative to each other, so for the clocks onboard of ...
3
votes
2answers
700 views

Relationship between Coordinate Time and Proper Time

While I was reading Ta-Pei Cheng's book on relativity, I was unable to derive the correct relationship between coordinate time $dt$ (the book defined it as the time measured by a clock located at $r=\...
0
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1answer
142 views

For a distant observer can a black hole form and grow in finite time? [duplicate]

Consider an observer at a significant distance away from a collapsing star. As such when a singularity is born at the core of the star the observer would never see it grow anymore than the ...
2
votes
4answers
718 views

A spool in Einstein's theory of special relativity

I would like to know how can we model a simple spool that unrolls at speed close to light (in the frame of the wire remaining on the ground AND in the frame of the translatory motion of the rolling ...
0
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1answer
218 views

Is the traditional explanation of why moving clocks run slow correct?

Like most people I struggle to get my head round special relativity. I read a superficially-plausible explanation for why a moving clock runs slow from the point of view of an observer in a rest frame ...
-1
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1answer
96 views

Does your arm time travel when moving?

I am no physicist and I wonder, due to Einsteins Special Relativity, does your arm when moving pass through time at a different pace than the rest of your body?
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2answers
367 views

Time speed in deep space

Time goes farster when you leave earths gravitational feild. Is there a danger that if we were in deep space and moving slowly we would age considerably compared to people on earth?