Questions tagged [twin-paradox]
42 questions
15
votes
10 answers
Twin Paradox: Still a Paradox?
Alright, so David Griffiths in his "Introduction to Electrodynamics" states that the Twin Paradox is not a paradox at all since the traveling twin returns to Earth. By returning to Earth, the twin had to reverse direction, thus undergoes…
Tyrion Lannister
- 159
13
votes
5 answers
Why isn't the symmetric twin paradox a paradox?
Two twin sisters synchronize their watches and simultaneously (from the earth frame) depart earth in different directions. Following a predetermined flight plan, each sister accelerates identically to 99.9%c and then returns home at the same time…
zip
- 139
8
votes
1 answer
Our Universe Can't be Looped?
With reference to the Twin-Paradox (I am new with this), now information of who has actually aged comes from the fact that one of the twins felt some acceleration. So if universe was like a loop, and the actually travelling twin again reached earth…
user23503
7
votes
2 answers
Twin paradox with two intertial frames in general relativity
I assume the twin paradox from special relativity is well known. I wish to focus on the apparent symmetry of the problem: both observer seems to move away from each other, and then come back. Yet, the outcome is asymmetrical.
That paradox is…
user40000
- 71
5
votes
3 answers
Twin Paradox, calculating spacetime intervals from both perspectives
I've very recently started to try to understand special relativity. I'm want to get a decent understanding of the twin paradox. I'll post what I've done so far and highlight what's gone wrong for me.
The situation is that Alice and Bob both begin at…
Lammey
- 633
5
votes
4 answers
How will the Twin Paradox become, for Time Dilation, if no acceleration was ever involved?
I think one catch in Twin Paradox was about the big acceleration that can turn back the traveling twin from light speed outward bound, to become light speed inward bound.
What if there is strictly no acceleration?
Peter is on a space ship,…
nonopolarity
- 332
5
votes
1 answer
Twin paradox, different starting locations
Let's say I have a twin who is at rest relative to myself and ten light years away from me, we are both in rocket ships. We have agreed that I will send a laser pulse and that when he receives it we will both accelerate to 80 percent speed of light…
David Barger
- 59
- 1
4
votes
1 answer
Twins paradox "corrected"
If you know a bit of special relativity, probably you've heard of the twin paradox. I would like to know: what happens if we take acceleration into account in the paradox. Usually we consider an instantaneous change of velocity for the moving twin…
4
votes
1 answer
Time dilation and the speed of light in the twin paradox
Suppose we look at the twin paradox where the twin traveling at high speed relative to an observer on earth has a clock which counts time by sending photons of light across a distance within the spaceship (perpendicular to the direction of motion)…
Chris Laforet
- 2,535
4
votes
4 answers
Twin paradox - observers counter orbiting Earth
Imagine three observers - one (A) stationary on the surface of Earth (latitude 0 deg) and two others orbiting the planet in the same circular equatorial orbit just in the opposite direction. When the orbiting observers B and C meet each other just…
Leos Ondra
- 2,265
3
votes
2 answers
What happens in the twin paradox if the ship doesn't return?
What happens if the twin in the spaceship doesn't return? Would he still be younger than his other twin? Is the symmetry broken simply by accelerating out of earth? If it is still symmetrical when he doesn't return, why do satellites have a…
Protoless
- 61
3
votes
2 answers
Is everything moving at c in a c unit circle
I was trying to explain special relativity to a few friends in a simple way and wound up with an analogy using a c unit circle.
I was using y as travelling in time, x moving in space; move in space and you are borrowing from your clock-speed. E.g.…
Captain Giraffe
- 154
3
votes
1 answer
Can you calculate unix timestamps (universal clock) from any planet?
Given the definition of unix timestamp as the number of seconds elapsed since January 1st, 1970 as GMT+0, without leap seconds, is it possible to create a universal clock that will generate the correct timestamp?
Is the current definition of a…
mirhagk
- 133
3
votes
0 answers
Dingle vs. Bondi: Twin Paradox Debate on BBC radio?
Herbert Dingle and H. Bondi debated the twin paradox on BBC radio before 1971. Does anyone have a link to the audio of this debate? thanks
Geremia
- 2,191
2
votes
0 answers
Twin Paradox - different approaches
What was the difference between Langevin's approach to the twin paradox and Max Von Laue's? I don't understand how Langevin tried to use the idea of absolute acceleration to explain the distinction in time difference?
(Also not sure if this is…
Sarah Jayne
- 625