# Twin Paradox Experiment

Discussion in 'The Cesspool' started by TonyYuan, Jul 24, 2023.

Not open for further replies.
1. ### TonyYuanGravitational Fields and Gravitational WavesRegistered Senior Member

Messages:
852
I once watched a lecture video about the paradox experiment of twins given by Professor Zhao Zheng of Beijing Normal University in China.
Brother B travels by spaceship, since the relative speed of brother A is v, the time of B will expand, and when B returns to the earth, B will be younger.
But we all know that speed is relative. We can also think that the speed of A relative to B is v, so the time of A will also expand, and A should be younger.
So which of the twins will be younger?

Professor Zhao Zheng replied:
Since B accelerates and decelerates during space travel, B will be younger. It seems that acceleration is the key factor in determining time dilation.

So let's imagine a scenario like this:
A and B are twins on Earth who left Earth on the same day.
The acceleration and deceleration processes of A and B are exactly the same, but A returns to the earth after reaching a speed of 0.1c, B maintains a constant speed after reaching 0.1c, and then flies forward for 1 light-year, and then returns to the earth.
The acceleration and deceleration processes of A and B are exactly the same, the only difference is that B maintains a constant speed and flies 2 light-years longer than A.

I really want to ask Professor Zhao Zheng, when A and B meet again on earth, who will be younger?
I also want to ask Professor Mao Shude, who will be younger?
I really want to ask those Einstein believers, don't you feel ashamed when you deceive the world? ! ! ! It's a crook's crime! ! !

to hide all adverts.
3. ### originHeading towards oblivionValued Senior Member

Messages:
11,890
B is younger.
No that is incorrect, it also matters how long there is a velocity difference between the 2 brothers.
B would be younger.
Anyone who has even cursory understanding of relativity would know that B would be younger.
Don't you feel ashamed claiming you have a PhD in physics when you don't know the answer to such a basic relativity question? If you really do have a PhD and you don't know this stuff because you've suffered a traumatic brain injury or something since you graduated then I will apologize for that comment.

I wonder if you would still have a problem with special relativity if you understood it?

Last edited: Jul 24, 2023

to hide all adverts.
5. ### James RJust this guy, you know?Staff Member

Messages:
39,426
Tony:

I think you forgot that you posted exactly the same scenario here previously and all your questions were answered in a previous thread.

This one is redundant, and therefore it is now closed.