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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).

Time dilation, in the theory of special relativity is the “slowing down” of a clock as determined by an observer who is in relative motion with respect to that clock.

The equation for calculating time dilation is as follows: $$t = t_0/(1-v^2/c^2)^{1/2}$$where: $t =$ time observed in the other reference frame
$t_0 =$ time in observers own frame of reference (rest time)
$v =$ the speed of the moving object
$c =$ the speed of light in a vacuum

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Time dilation for a moving electronic clock

Is this a correct application for the time dilation theorem? Suppose an electronic clock has a copper wire of length $d$, which allows the electrons to take $t$ seconds to complete a cycle on the $d$-long copper wire, in the electronic clock. Then,…
caveman
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If time dilation can slow time down, is there away to speed time up?

Okay, I know the title is really confusing but I couldn't find words to explain it sorry. Pretty much what I mean is, if I can get in a lightspeed spaceship moving away from earth, time slows down for me. So one year for me will be 20 earth years or…
LostPecti
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Gravitational time dilation contradicts the concept of cosmic time

According to relativity theory (gravitational time dilation), the observed pace of a clock depends on the strength of the gravitational field at the clock and at the observer. Isn't this at odds with the concept of cosmic time in big bang cosmology:…
Anton
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Are there more causes besides Gravity and Velocity that cause time dilation?

Albert Einstein discovered that both gravity and velocity alter time in a given reference frame relative to the time of an observer in a different reference frame. If gravity and velocity both alter the passage of time, is it possible that other…
Tommy Sanfilippo
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Would a rapidly-rotating object experience time dilation?

Suppose you have an object that is rotating rapidly about its central axis. Let's say that the rotation is so fast that tangential velocity of the outermost part of the object is nearly relativistic. For example, it could be a radioactive molecule…
Superbee
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Would things experiencing time-dilation seem to be moving in slow motion to an observer?

I recently watched a documentary about relativity and time travel. It explained how time slows down close to massive objects and then it tried to visually show it by showing people moving in slow motion around the pyramids (after clarifying that…
Achilles
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Can light travel faster?

I'm on Earth. Joel is on a planet orbiting near a black-hole's horizon. Every year on Joel's planet is equivalent to 10000 years on Earth due to the gravity of the BH. The two planets are 10000 light-years apart. I send a message to Joel via light.…
kptlronyttcna
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Time dilation under different references paradox

I couldn't figure this out... I understand that if Alice is moving relatively to Bob at a high speed, Alice's time elapses slower than Bob's. So when Alice is back to Bob and compares the clock, Alice's shows 10:01 but Bob's shows 10:10, for…
leonard
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Time dilation in the dark

i am just starting to learn about relativity. One of the first big concepts the book teaches is time dilation and one of the first examples is the one many of you probably have heard of the two spacecraft moving very fast and one emitting and…
Anthony B
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Time Dilation Experiment

I am currently thinking of doing an experiment for science fair involving time dilation which will use the equations for both time dilation based off of speed and for gravitational dilation to determine if there is a speed and orbit altitude a…
gotnull
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Is talking about "now" at great distances always meaningless?

I've read that asking "what's happening right now on a planet P that is N light years away from Earth?" is a non-sensical question due to time-dilation at great distances. But I wonder about the following: If we send a message to planet P, that will…
Scarlain Stimolon
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Does a relativistic rocket lead to time dilation in the space surrounding the rocket?

This question was asked a few years ago, but I'm looking for more complete answers. And of course I recognize that any dilation effects would be extremely small. If a rocket is traveling at relativistic speeds, then certainly there is time…
foolishmuse
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Near light speed space travel to more than one star and back to earth?

I'm afraid this one is kind of a yes or no question, because I think I would get lost in the discussion of metrics, etal. As a layman, I get that if you travel fast enough (by accelerating and decelerating of course), that when you get to a…
Jack R. Woods
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Gravitational Time Dilation Scenario

Here's my scenario: One person with a clock on planet A, one person with a clock on planet B. Planet A's mass is greater than that of planet B. From what I understand, from each person's point of view, the other planets clock appears to be moving…
Brainless
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Time dilation in the movie Interstellar

I know that the science in movies is questionable and sometimes ridiculous but I would think this question would have been more obvious to the script writers. When they visited Miller's planet they were almost killed by a re-occurring tidal wave. In…
Bill Alsept
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