Linked Questions

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What slows down time relative to an observer: super gravity or super speed? [duplicate]

Sounds like after the Interstellar movie, ppl are talking much more about time slowing down near a black hole, instead of traveling close to the speed of light. My personal hobbyist experience was ...
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2answers
448 views

Confused about the concept of time and time dilation [duplicate]

I am having a hard time understanding what is time. If scientists define time as a multiple of caesium frequency, then time itself is dependent on motion, so what if I have a number of particles that ...
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1answer
472 views

What is the deep reason of length contractions and time dilations? [duplicate]

In the theory of relativity, a spacetime can have length contractions or length expansions and time can have time dilations or expansions. In theory of special relativity, any physical object with ...
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0answers
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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 ...
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1answer
47 views

Is gravitational time dilation nothing more than kinematic time dilation in another form? [duplicate]

Once we get down to the quantum level, mass is derived directly from energy. From Wikipedia: Most of the mass of hadrons is actually QCD binding energy, through mass-energy equivalence. This ...
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0answers
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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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14answers
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What is the proper way to explain the twin paradox?

The paradox in the twin paradox is that the situation appears symmetrical so each twin should think the other has aged less, which is of course impossible. There are a thousand explanations out there ...
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4answers
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Does velocity or acceleration cause time dilation?

What causes time dilation? Acceleration or velocity? I've seen multiple comments on this forum that assert velocity is the cause, but that doesn't seem right to me. You can't have velocity without ...
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7answers
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Can a ultracentrifuge be used to test general relativity?

With today's ultracentrifuge technology, they can spin so fast that the sample can be subjected to accelerations of up to 2 millions Gs. That is equivalent to two solar masses. Has someone tried to ...
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2answers
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Why is spacetime interval invariant under Lorentz transform?

We can verify that the spacetime interval is invariant through brute force computation. Is there a deeper reason why the interval is invariant under Lorentz transform?
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7answers
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Why does gravity cause time dilation?

I know there have been several posts asking the same or similar questions, but I haven't been able to grasp this from reading any existing questions. My question is: why does gravity cause time ...
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2answers
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Why does time dilation cause you to age slower? And is time considered relative to the observer?

I understand that the higher your velocity the slower light will move. But how does time itself slow down while you are moving faster?
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3answers
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How to describe arbitrary accelerations in special relativity

Describing acceleration in special relativity is in principle straightforward, and for simple cases the resulting transformations are simple. Examples include circular motion and constant acceleration ...
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1answer
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What happens if someone travelling just under the speed of light makes a telephone call?

Apart from the possibility that radio transmission will not work, what would happen if someone travelling fast enough relative to another individual to experience significant time dilation made a ...
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2answers
908 views

Non-reciprocal time dilation

Is this report describing Absolute Lorentz Transformation legitimate or pseudoscience? The reporting sounds like the kinds of things I see in newbie's questions on the twin paradox, or crackpot ...

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