Questions tagged [time-dilation]
This tag is for questions regarding the 'time dilation' which is the lengthening of the time interval between two events for an observer in an inertial frame that is moving with respect to the rest frame of the events (in which the events occur at the same location).
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Which wins the race, the neutrino or the photon? [closed]
You have an emitter at A and a reciever at B. Exactly half way between them is a star. The emitter simultaneously emits a burst of photons as well as a burst of moderatly high-energy neutrinos. The ...
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Can a rotating or charged object have time speed up as you approach?
The Reissner–Nordström metric has a gravitational time dilation defined by
$$y=\sqrt{\frac{r^2}{Q^2+r(r-2M)}}
.$$
Note that there is a charge squared term there, but the term for the mass in linear.
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Inertial frames, the speed of light and contraction and dilation of time
From the postulate that the speed of light is constant how it follows that if we have a static inertial frame and next moving inertial frame and we send the beam once in the direction of the movement ...
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Does a distant observer see the light for a longer duration due to the effect of time dilation?
I am currently learning about the basics of relativity and the concept of time dilation. I was thinking of an event as described below and curious to know what would happen
Suppose, one shines a laser ...
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Periodically signaling object falling into a black-hole
Say that a distant, stationary (relative to the star) observer signals every 1-second (by the observer's own clock) to an object free-falling into a black-hole.
Will the frequency of the signals ...
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Rindler Time Dilation vs Gravitational Time Dilation in Accelerating Refernece Frame
I am trying to reconcile Rindler time dilation with gravitational time dilation between two points in an accelerating frame of reference separated by a distance d (e.g. 1 light-second).
As far as I ...
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Imagined spacecraft acc/decelerating at 1g to/from near $c$: Does the destination star not move faster than $c$?
Motivated by Andy Weir's novel Hail Mary, I was just reading an answer regarding the time needed to travel between stars with a constant acceleration (and deceleration after the mid-way point). Due to ...
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Looking for an expression of gravitational time dilation as a function only of mass density, without any reference to distance
Setup for the question: Under the Cosmological Principle, mass and energy density can be treated as homogenous and isotropic at large scale. This Principle can be applied to any scale in a model. We ...
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Questions about black holes and time dilation, with reguards to objects passing the event horizon
First things first, from how I understand it if we assume a black hole is non-rotating and uncharged, and does not emit any Hawking radiation, and an object fell into the black hole, then from the ...
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Time travel to the future [closed]
According to Einstein's special relativity, time passes slower for the faster object. So, let's travel in space and gradually increase the velocity to near the speed of light. And, I think we don't ...
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Length contraction on a train measured with an interferometer
Imagine I took an L-shaped interferometer on a train, and adjusted the arm lengths such that there was total destructive interference at the interferometer output, then placed one arm in the direction ...
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Time dilation, an example of jumping through time
so let's say that there is someone who are 20 years old and are gonna die at at the age of 30 which is 2030 so he is 20 years old at 2020, so if he jump with the time dilation at 50% the speed of ...
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Gravitational Time Dilation, Current or Future Events
I read somewhere, that if a Martian in his spaceship was put into a deep sleep, roughly 10 million years ago, at a height of 10 KM above where London now is, due to Gravitational Time Dilation on ...
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Could time be scale-relative, in the way mass and forces are energy-scale-dependent in quantum field theory?
In relativity, each observer experiences their own proper time as normal, even though time can pass at different rates when compared between frames—due to either velocity (special relativity) or ...
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GR and SR time dilation of light
I'm wondering about GR and SR time dilation and light.
First, we put a mirror on Mercury and flash a laser at it. The return time to Earth is 10:00 minutes. Now we dig a big tunnel right through ...
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Can one ever cross the event horizon of a black hole if it evaporates in finite time due to Hawking radiation? [duplicate]
In classical general relativity, a freely falling observer can cross the event horizon of a black hole in finite proper time. However, from the perspective of a distant observer, the falling object ...
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Paradox in Gravitational Time Dilation and the Equivalence Principle in an Accelerating Elevator
In General Relativity, the equivalence principle suggests that an accelerating frame is equivalent to a gravitational field. Consider an elevator in deep space accelerating upward at a constant rate (...
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Does light of higher frequency (higher energy) appear to travel slower given that time dilates in the presence of energy?
Given that:
Light of higher frequency carries more energy
Time dilates in the presence of energy, and moreso in the presence of more energy
Motion in a more time-dilated space appears slower to a ...
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How is time dilation symmetry broken?
In special-relativity, if observer A sees observer B moving with constant velocity $v$ then B is subject to time dilation gamma < 1. Symmetrically, B observes A to move with velocity $-v$ and ...
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How do you calculate time dilation if there's two gravitational pulls acting at once?
I was wondering how you'd calculate time dilation if there's two masses acting on you at once. For example lets say I wanted to calculate the time dilation between Earth and PlanetB (I just made that ...
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Will a person aboard space ship approaching a black hole, experience slowing down of time?
The space ship is heading towards black hole so the time will slow down for the people aboard the shop
However will the people aboard the ship notice this slow down of time as the ship gets closer to ...
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Is the geoid a redshift isosurface? [duplicate]
This question is inspired by this question about timekeeping.
I understand the geoid to be the surface matching the shape that the water on Earth's crust would take
Under the effect of Earth's ...
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Can time dilation between two clocks be communicated at a distance?
There are many questions on stack exchange related to time dilation, and I think this answer gets closest to answering my question, but not quite (or at least not in a way that it is clear to me). I ...
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Net Time Dilation for a Free-Falling Object as Seen from Infinity [duplicate]
Gravitational time dilation at a given radius $r$ around a mass looks equal to the special‐relativistic time dilation you’d get if you moved at the local escape velocity. For an object freely falling ...
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Does the twin paradox hold in a universe that's empty except for the twins?
I recently obtained a used copy of Shadowitz's obscure book on Special Relativity, in which he makes the following astounding claim (which I have not seen elsewhere) concerning the twin paradox with ...
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