# Tag Info

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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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, ...

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 ...

### 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 ...
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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 ...
1 vote

### 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 ...
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1 vote
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 ...
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1 vote

### 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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### 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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### 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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### 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 ...
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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 ...
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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 ...
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1 vote
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 ...
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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 ...
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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 ...
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