New answers tagged time-dilation
2
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Something about length contraction still feels off, is there any reason we talk about this effect in terms of length
You are overlooking two crucial points. Firstly, there are measurements that can be performed to distinguish a short object passing slowly from a long one passing quickly. Secondly, the concept of a ...
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-1
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Something about length contraction still feels off, is there any reason we talk about this effect in terms of length
Answered through replies:
In the muon case, there's no difference between the earth moving extra fast vs lengths contracting. However when you run an experiment, this velocity dilation idea is stupid, ...
3
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Something about length contraction still feels off, is there any reason we talk about this effect in terms of length
You are very mistaken. There is a lot of equivalences, but you do not seem to have captured them correctly.
In the muon case, from the muon's perspective, it is the Earth (and space between Earth and ...
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0
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How does conservation of energy work with time dilation?
Let's say a box moves at speed 0.87 c along the equator of the earth. Inside the box there are a light bulb, a light sensor, and a battery that powers the bulb.
When the battery is empty, a truck ...
- 2,106
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How does conservation of energy work with time dilation?
Momentum is only conserved in four dimensions.
Acceleration in N Dimensions is always rotation in N + 1 dimensions. In a dark room, a candle on the edge of a rotating platter appears to be ...
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1
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Confusion about time appearing to run slower at bodies with higher gravitational forces
The ISS doesn't simply float 260km above the Earth's surface. It orbits the Earth. It flies the whole way 'round the Earth every 93 minutes—approximately 7600 meters per second. That's fast enough for ...
- 215
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Accepted
Confusion about time appearing to run slower at bodies with higher gravitational forces
The person in space is not somehow on the outside of the picture looking at the high frequency squiggle on the surface and the low frequency squiggle in pace. Instead, they only see the low frequency ...
- 67
1
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How does conservation of energy work with time dilation?
We have $\gamma=2.$ This doesn't only mean that when time $t$ passes at the origin of the B frame, time $2t$ passes in the A frame; it also means that if the battery contains energy $E$ according to B,...
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2
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Does a pendulum violate general relativity?
You are confusing two notions which are totally different :
the gravitational potential : the deeper into a (negative) gravitational potential, the slower the clock. Whatever method you use to ...
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2
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Does a pendulum violate general relativity?
You are wrongly confusing two separate effects, namely the curvature of spacetime and the effect that curvature has on the performance of a device that measures time.
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0
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Can there be a theoretical synchronised ‘now’ moment at all points across the universe?
Defining a common 'now' in flat spacetime is impossible, because all of the points that are simultaneous for you will not be simultaneous for anyone moving relative to you. When you imagine that you ...
- 26.7k
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Time Dilation Special Relativity
Strictly speaking, you need to give Jack one clock and Bill two, since Bill needs to record the time of Jack at A and then Jack at B. Anyway, assuming A and B are stationary relative to Bill, then ...
- 26.7k
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Time Dilation when they meet
Yours is a common misunderstanding and it arises because you assume, incorrectly, that time dilation involves the comparison of one moving clock with one other clock. Time dilation isn't symmetrical ...
- 26.7k
1
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Accepted
If $\Delta t_0 < \Delta t$ then does it mean that first light signal will reach receiver faster or earlier than second light signal?
In both of the frames, there are two events, one being the emission of the light signal at A, the other being the arrival of the light signal at B. I think that your confusion arises from the fact ...
- 26.7k
3
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How do photons travel through time?
You’re fundamentally right: an object moving at exactly $c$ does not experience proper time. In the limit as $v\to c$, time dilation is infinite (so an external observer sees their clocks as having ...
- 1,930
0
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How does special relativity explain the exchange of things between two observers?
Yes, in the scenario you have described there is a difference in expectation about how many oranges should be exchanged. That is a natural consequence of Special Relativity. It is there because you ...
- 26.7k
6
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Accepted
How does conservation of energy work with time dilation?
Energy is proportional to power multiplied by time. For an observer that sees the light bulb as moving, it is emitting light at a lower power for a longer duration, but the total energy used up $(\...
- 7,696
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How does special relativity explain the exchange of things between two observers?
The inclusion of an exchange lead to different outcomes.
The scenario is interesting and counterintuitive and can appear to lead to different outcomes, but in relativity outcomes are guaranteed to be ...
- 7,696
6
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How does conservation of energy work with time dilation?
Ignoring all the Doppler shifting concerns etc., the bulb just glows at a lower intensity.
That is, everyone agrees that in this thing’s rest frame, it is a 100 watt light bulb, it is consuming 100 ...
- 38.6k
6
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How does special relativity explain the exchange of things between two observers?
As with more than 90% of the SR “paradoxes”, this one is simply due to ignoring the relativity of simultaneity.
In each observer’s frame the other orange tree is producing oranges slowly, but due to ...
- 105k
2
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If $\Delta t_0 < \Delta t$ then does it mean that first light signal will reach receiver faster or earlier than second light signal?
You are measuring both cases in you own reference frame, someone moving with B will also measure that it takes a time $\Delta t_0$. Because $\Delta t_0 < \Delta t$, you see that in your reference ...
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5
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Confusion about time dilation
The clock ticks (in its reference frame) every second, so it
travels 0.5 light seconds between ticks, making each tick 0.5 seconds
longer for a total of 1.155 + 0.5 = 1.655 seconds between ticks.
...
- 7,696
2
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Confusion about time dilation
The right answer is 2) as already pointed out.
The mistake in 1) is that you forgot to time-dilate the 0.5s
Total period in your reference frame = 1s*gamma + 0.5s*gamma
=1.5 *1.155s = 1.732s
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14
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Accepted
Confusion about time dilation
Calculation 2 is correct. That is how you determine the tick frequency working entirely in your reference frame.
The same calculation can be done in the reference frame of the clock, but you must ...
- 1,781
1
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Gravitational redshift and time dilation
You can watch a clock continuously as you drop it to a lower altitude, wait a while, and then raise it up again. While it's at the lower altitude it will appear redshifted. While you're lowering it, ...
- 28.3k
2
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Gravitational redshift and time dilation
If this is the case, when you bring the earth clock up to the same
height as the observer, wouldn't this "illusion" of delay go away, and
the two clocks should show the same time?
It is not ...
- 7,696
1
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Gravitational redshift and time dilation
Time does actually flow slower in the presence of gravitational fields. This has been observed at the quantum scale, when atomic clocks (relying on a quantum oscillator that has a very precisely-known ...
- 1,930
0
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What will going near the speed of light would look like?
In the first case (where B believes A to be in motion), if time
dilation is supposed to make person A move slowly (from B's frame of
reference), will B just see an almost stationary picture of person ...
- 7,696
0
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What will going near the speed of light would look like?
Let's get rid of the issue of moving towards or moving away by saying that A is traveling in a circle around B and B is rotating to keep a constant eye on A. And then we'll say that A is a long ...
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What will going near the speed of light would look like?
If you really mean 'see', as in experience in real time with their eyes, then they won't see anything. If I pass you at the speed of light, I will be at an easily visible distance for too short a ...
- 26.7k
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What will going near the speed of light would look like?
The situation becomes clear if we note how the clocks would be compared. One way is to have one clock per wagon in the train, all of them synchronized in the train's frame.
The bystander would always ...
- 16.9k
3
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What will going near the speed of light would look like?
If A is moving toward B, he will see B's clock ticking in "fast forward", but will realize this is partly because B keeps getting closer, so light from each tick of B's clock arrives faster ...
- 16.4k
-2
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What will going near the speed of light would look like?
The situation is symmetric. A sees B's clock tick slower, and B sees A's clock tick slower. At very nearly the speed of light that time dilation will make each person appear to be not flowing through ...
- 1,930
-1
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Explaining the phrase "as viewed by A, clock $\mathfrak B$ appears to be ticking faster than clock $\mathfrak C$"
"When viewed from the surface of the Earth, the clocks on the satellites appear to be ticking faster than identical clocks on the ground.".
This ubiquitous terminology used in the context of ...
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