# A thought experiment to aid my undertsanding

1. Oct 16, 2009

### mtiller

H'mmm, my math and understanding isn't up to the discussion of relatavistic mass, so I am going to propose a reasonably simple thought experiment and if anybody can give me an answer, it would be much appreciated.

A man is on a spaceship that accelerates to a point where time dilation compared to someone on earth is at a factor of 60. So 1 second passes for the space travelller when 1 minute passes for the ground observer.

My question is this.

Mass dilation occurs at the same rate as time dilation, so simplisticly the man masses 60 times what he does on earth. Is his heart able to pump blood around his body, or does he asphyxiate because the heart can't pump that much mass?

I am hoping someone may be able to answer the question in a way I can understand. (I am able to read and understand John Gribbin's books)

Mark

2. Oct 16, 2009

### Staff: Mentor

His heart is able to pump blood around his body in one reference frame so, according to the first postulate of relativity it must be able to pump blood aroun his body in all reference frames.

3. Oct 16, 2009

### HallsofIvy

The body, heart, and blood are all in the same frame of reference. As far as they are concerned, he still has exactly the same mass as he did before he accelerated. That's the whole point of "relativity". His mass has increased only relative to a frame of reference with his initial speed.

4. Oct 17, 2009

### mtiller

Ah! OK, thanks to both of you.