Does Earth's Movement Affect the Twin Paradox in Space Travel?

In summary, the modified twin paradox scenario involves one twin travelling with the Earth and the other stationary twin being reached by a star that also moves with the Earth. This results in the stationary twin aging less than the traveling twin. However, adding a 10 ly long rod that instantly accelerates complicates the analysis and is not necessary. The scenario can be analyzed from multiple frames of reference, but all will result in the conclusion that the traveling twin aged less than the stationary twin.
  • #36
The issue is not instantaneous acceleration but rather simultaneous acceleration along all parts of the object. You have no choice about how you accelerate an electron.
 
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  • #37
if an electron shrinks when accelerated then is it not right to say even if simultaneous acceleration is applied to all particles of the rod, every subatomic particle shrinks resulting in the net reduction of rod's length?
 
  • #38
It was your idea to accelerate all the particles of a rod simultaneously. Maybe you're beginning to see that it might be easier said than done.
 
  • #39
ghwellsjr said:
It was your idea to accelerate all the particles of a rod simultaneously. Maybe you're beginning to see that it might be easier said than done.
yes it was. But you said when something like that was done, rod will expand. I am now talking about that.
 
  • #40
Do you understand what acceleration means? Do you understand that the integral of acceleration is speed and the integral of speed is position? Do you understand that if you apply the same acceleration to two items that are a certain distance apart, they will remain that same distance apart all during the acceleration and after it is all over, they will still be the same distance apart although moving at some speed relative to their starting condition?
 
  • #41
Tea Jay said:
Does that count as accelerating the rod? Or just crushing one end of it?
It is acceleration, just not rigid body acceleration.

Tea Jay said:
Would there be a difference between doing the above, and firing a speed of light piston into a bowl of jello? Would the bowl of jello undergo time travel where it was impacted, but not at the unperturbed end? Would the contraction of spacetime at the impact prevent the transmitted forces from being transmitted to the rest of the jello?
There is no such thing as a speed of light piston, so no time travel to worry about. The forces are not prevented from being transmitted in any way, they are just transmitted at the speed of sound in the jello. For jello the speed of sound is low enough that we can easily visualize the transmission of the force, but compared to the speed of light, even the speed of sound in steel is jello slow. That is why the analogy is useful.

Tea Jay said:
If I did have a rod of jello, I'm not sure what means I'd use to get it to accelerate, given its lack of purchase so to speak.
When I wish to accelerate jello I typically use a spoon :smile:

Tea Jay said:
But let's say we have means to accelerate a jello rod instantaneously...and in a way that only accelerates one end of it...how do we get instantaneous acceleration without movement? If we just happened to have such a rod when at rest, and then, anytime later when it was traveling along at the desired speed...and just started the measurements before and in flight so to speak, wouldn't we get the same readings as what was desired to be obtained by the instantaneous acceleration example?
That is just a useful approximation, don't worry too much about it. Think about a constant force which accelerates from rest to a fixed speed. The distance traveled is a function of the force, and in the limit as the force goes to infinity the distance goes to zero.
 
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  • #42
Snip3r said:
if an electron shrinks when accelerated then is it not right to say even if simultaneous acceleration is applied to all particles of the rod, every subatomic particle shrinks resulting in the net reduction of rod's length?
You are Probably thinking of what is called Born-rigid acceleration.

http://www.mathpages.com/home/kmath422/kmath422.htm
 
  • #43
@ghwellsjr and DaleSpam
thanks :)
 
<h2>1. How does Earth's movement affect the Twin Paradox in space travel?</h2><p>Earth's movement does not have a direct effect on the Twin Paradox. The paradox is a thought experiment that highlights the effects of time dilation in special relativity, which is a fundamental principle of physics. Earth's movement may be a factor in determining the relative velocities and distances between the traveling twin and the stationary twin, but it is not the cause of the paradox itself.</p><h2>2. Does Earth's rotation cause time dilation in the Twin Paradox?</h2><p>The rotation of Earth does not directly cause time dilation in the Twin Paradox. Time dilation is a result of the relative velocities between two observers, and Earth's rotation is not a significant factor in determining these velocities. However, Earth's rotation may contribute to the overall motion of the traveling twin and affect the time dilation experienced during their journey.</p><h2>3. How does Earth's orbit affect the Twin Paradox in space travel?</h2><p>Earth's orbit around the sun does not have a direct effect on the Twin Paradox. The orbit may contribute to the overall motion of the traveling twin, but it is not a determining factor in the time dilation experienced during their journey. The relative velocities between the traveling twin and the stationary twin are the primary cause of the paradox.</p><h2>4. Can the Twin Paradox be explained by Earth's movement?</h2><p>No, Earth's movement cannot fully explain the Twin Paradox. While Earth's movement may play a role in determining the relative velocities and distances between the traveling twin and the stationary twin, it is not the sole cause of the paradox. The paradox is a result of the principles of special relativity, which go beyond the movement of Earth.</p><h2>5. How does the Twin Paradox account for Earth's movement in its explanation?</h2><p>The Twin Paradox does not directly account for Earth's movement in its explanation. The paradox is based on the principles of special relativity, which do not rely on Earth's movement for their validity. However, the movement of Earth may contribute to the overall motion and relative velocities between the traveling twin and the stationary twin, which can affect the time dilation experienced during their journey.</p>

1. How does Earth's movement affect the Twin Paradox in space travel?

Earth's movement does not have a direct effect on the Twin Paradox. The paradox is a thought experiment that highlights the effects of time dilation in special relativity, which is a fundamental principle of physics. Earth's movement may be a factor in determining the relative velocities and distances between the traveling twin and the stationary twin, but it is not the cause of the paradox itself.

2. Does Earth's rotation cause time dilation in the Twin Paradox?

The rotation of Earth does not directly cause time dilation in the Twin Paradox. Time dilation is a result of the relative velocities between two observers, and Earth's rotation is not a significant factor in determining these velocities. However, Earth's rotation may contribute to the overall motion of the traveling twin and affect the time dilation experienced during their journey.

3. How does Earth's orbit affect the Twin Paradox in space travel?

Earth's orbit around the sun does not have a direct effect on the Twin Paradox. The orbit may contribute to the overall motion of the traveling twin, but it is not a determining factor in the time dilation experienced during their journey. The relative velocities between the traveling twin and the stationary twin are the primary cause of the paradox.

4. Can the Twin Paradox be explained by Earth's movement?

No, Earth's movement cannot fully explain the Twin Paradox. While Earth's movement may play a role in determining the relative velocities and distances between the traveling twin and the stationary twin, it is not the sole cause of the paradox. The paradox is a result of the principles of special relativity, which go beyond the movement of Earth.

5. How does the Twin Paradox account for Earth's movement in its explanation?

The Twin Paradox does not directly account for Earth's movement in its explanation. The paradox is based on the principles of special relativity, which do not rely on Earth's movement for their validity. However, the movement of Earth may contribute to the overall motion and relative velocities between the traveling twin and the stationary twin, which can affect the time dilation experienced during their journey.

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