## Special Relativity Made Adorable

by Desiree Schell on February 23, 2011One comment

It’s story time!

Einstein’s Twin Paradox, explained in this surprisingly cute video.

A Tale of Two Twins from Yuanjian Luo on Vimeo.

by Desiree Schell on February 23, 2011One comment

It’s story time!

Einstein’s Twin Paradox, explained in this surprisingly cute video.

A Tale of Two Twins from Yuanjian Luo on Vimeo.

## One comment

wisp on February 25, 2011 at 8:40 pm. #

It seems to VIOLATE relativity.

The effects of time dilation happen during the whole time the two frames of reference move at great speed relative to each other, and i don’t see why it should have anything to do with the acceleration experienced by one of the subjects (even though gravity time dilation is a fact). Because… What if each of the two acceleration events happened very quickly, like a ball being hit with a bat? What if a device like a transporter from Star Trek (which Michio Kaku predicts will be available 100 years from now) materializes a twin in an already speedy frame of reference?

I suspect the acceleration is not the relevant asymmetry between the twins, but this one: The astronaut twin didn’t use one frame of reference, but TWO. One on his way up and one on his way back.

The important thing is the change of velocity, which implies a change in the frame of reference. I say it’s not acceleration per se what matters because we would confuse it with gravitational time dilation (General Relativity tells us that acceleration and gravity are the same thing), and that’s not it. The effects of gravitational time dilation are only noticeable during the acceleration, and in the case of the astronaut twin the effects of having changed velocities accumulate during the whole lapse of his voyage (which is multiplied by his Lorentz factor).

Right?