All Questions
Tagged with time reference-frames
170
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Is the size/age of the universe dependent on your velocity? [duplicate]
As Photons do not experience time or space, then according to my thought experiment, all photons must occupy some kind of singularity as well as what WE observe from earth.
I was also thinking that ...
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How to measure time in reference frame with clock?
I considered example of time dilation with light clock. I have a question about measuring time in reference frame with clock.
If we know that clock move from A to B in the reference frame with clock ...
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How to measure time difference in different frames of reference in relativity
I saw this post about measuring the time difference between two clocks and I couldn't understand Ajay Mohan's answer even after his edit.
I tried to draw a picture of what I think actually happens.
...
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Notation confusion about time derivative of a vector in a rotating frame
As far as I can tell, this question, or similar ones, have been asked a number of times:
Derivation of the time-derivative in a rotating frame of refrence
Time derivatives in a rotating frame of ...
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2
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Justification of string breakage in Bell's Spaceship paradox from observer's frame
In Bell's Spaceship Paradox, are there any direct observations that the stationary observer can make that would justify the breaking of the string without taking into consideration as to what's taking ...
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11
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Sabine Hossenfelder says time dilation is due to acceleration in the twin's paradox. Is this true?
Sabine Hossenfelder says time dilation is due to acceleration in the twin's paradox. Is this true?
At 12 minutes into this video https://www.youtube.com/watch?v=ZdrZf4lQTSg, Hossenfelder states, &...
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5
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Is relativity of simultaneity an "observer issue"?
There are some threads about this, but some answers seem to disagree.
First, this is what Einstein said on this matter:
The light rays emitted by the flashes of lightning A and B would reach him ...
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Could a civilisation use “inverse time dilation” to live longer?
If an observer were to live near a black hole of sufficient mass, half an hour could elapse for them, but the outside universe could progress hundreds of years. This is due to time dilation.
We know ...
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Using position of a free particle to measure time
Hartle, gravity
An observer in an inertial frame can discover a parameter t with
respect to which the positions of all free particles are changing at constant rates.
This is time
Then goes on to say
...
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3
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533
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Using time dilation to find universal frame of reference
Before I ask this question, I just want to clarify that I am by no means an expert and that this question most likely came about due to my ignorance on the subject. If this is the case, please let me ...
- 567
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How fast can clocks go?
We know that clocks can move slower when near a massive object, however, how FAST can clocks go? Can clocks go as fast as they want?
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How "accurately" does the CMB tell the age of the universe?
Just to clarify, I am not asking about clock accuracy per se at all. The reason I am asking this question stems from the fact that on this site, most questions about the age of the universe answer ...
- 29k
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Does material time derivative physically make sense?
where $u$ is the velocity field.
So one term of the material time derivative tells us how much the field is changing with its motion along particle, and another when it's fixed in position and ...
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How can we speed up time using relativity?
This is a thought experiment question on time dilation/ relativity etc.
'Jack McCormick' leaves the Earth at 99.99% the speed of light. Later, he looks at his wrist watch and his wrist watch tells him ...
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Is proper time a definition in GR?
Where does come from in GR that the proper time between two events measured by an observer is the length of his worldline calculated using the metric? Is it assumed or postulated in analogy with ...
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