The younger Twin

Thanks to Amrita for asking this question about Twin Paradox. It was a thoughtful question, and the right questions at right time can lead to Big progress and good understanding. I have quoted below this dialog as it is. It reminds me of one story from Puranas, which indicates that the superfast(close to c) time travel could have been possible earlier.

The story goes like this:-

There was a King and he had a pretty daughter. He couldn't find a suitable groom for his pretty daughter, and so he set himself and her on a travel to Brahmaloka. When he reached Brahmaloka, Brahma gave him blessing and asked him to marry her to the King of a certain country on Earth. Happy, the King traveled back to the Earth with his daughter. Coming to the earth, he was so surprised that his city, his buildings and people were not there at all. In his City, he himself and all the human beings were as tall as a coconut tree. And he was shocked to see the human beings in the size of 5-6 feet, so small compared to him and her daughter. Upon inquiry, the King got to know that their civilization used to exist several thousand centuries ago! Though the King and his daughter had only aged by an year or so, the time had elapsed much faster on the earth. The King got his daughter married to a noble Prince and they lived happily ever after.

Conclusion:- the King and his daughter had traveled very fast, and Brahma loka could have been a really far away place!

Thanks

Amrita said...

Hi,I was reading theory of relativity and found that "Time Dilation is a reciprocal effect",if it is so then why in case of twin paradox,one of the twins who goes to the space and come back, remains younger than the other who stays back on the earth!

November 23, 2009 10:41 PM

Abhay Karnataki said...

good question.
now here we have to understand that though there is no single absolute inertial frame for all observers, you can definitely make out if your frame is inertial or not.
if you are in a car and close your eyes, then even when the car turns, your body bends to one side or other, showing the acceleration, and hence non-inertial nature of the frame attached to the car.
Similarly, in the twin brothers travel, one brother is definitely getting accelerated at the end of the journey, and he is the one who comes out to be younger. the brother in his rest frame doesn't experience any acceleration at any time.
if the other brother would not have returned any time, then the time dilation is exactly reciprocal.

November 23, 2009 10:47 PM

night sky of the World

night sky of the World

Above picture shows how much city light is emitted in different parts of the world at night... recorded by some satellites. More info is here:- night sky in the World. interesting, isn't it!