Portal Discussion: Human at Speed of Light

[jannin]

Hi all,

I am very new to this forum so please let me know if I have posted this in the wrong place, and thanks in advance for any replies :)

Backstory:
My friends and I were playing a game called Portal in which you can place two portals (each of which leads to the other). We were discussing what you could do if you placed one portal right above the other (ie, one in the ceiling and one in the floor) and then began to fall through. From there, the conversation led to what would happen to a person falling through the portals in a vacuum (therefore ignoring air friction).

Question:
What would happen to a person as they approached light speed at the acceleration of gravity? Assume for the sake of the question that this person does not need to eat/breathe/sleep/etc, and that the portals are matterless and do not produce any sort of friction.

Thanks again!

 

[A.T.]

My friends and I were playing a game called Portal

Nice game requiring some physical thinking.

We were discussing what you could do if you placed one portal right above the other (ie, one in the ceiling and one in the floor) and then began to fall through.

You would have an perpetuum mobile, which is ruled out by most physical theories. But if you want an idea, how the world would look like to you while moving close to c:
http://www.spacetimetravel.org/bewegung/bewegung7.html

 

[JesseM]

You would have an perpetuum mobile, which is ruled out by most physical theories.

Apparently it is theoretically possible to do something like this with a pair of wormholes, but energy conservation is preserved by changes in the mass of the two wormhole mouths; see pervect's post #6 on this thread. He says:

Energy will be conserved in this case via the gain and loss of mass of the mouths of the wormhole.

This, however, will not stop the "perpetual motion" machine from operating :-(. It is possible that some unanalyzed mechanism might eventually cause the wormhole itself to fail, other than that this is a definite issue.

The wormhole mouth at the bottom will get "heavier" because of all the matter entering it. The worm hole mouth at the top will get lighter, eventually acquiring a negative mass!