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By dziadek1990   |   Watch
Published: May 27, 2011
© 2011 - 2019 dziadek1990
I have done a thought experiment about the famous BRAIN-F*CKER from the game "Portal":
"What would happen if you put a portal through another portal?".

The above diagrams feature the results of my thinking.

diagrams A and B show the meanings of the symbols:
- In A we see that only the side of a portal, that has squares sticking out can be entered (or exited).
- In B we see that hollow and filled-in squares represent upper and lower edges of a portal
and how swapping their places makes a person to face a different direction after exiting.

Now the portal-in-portal thought experiment:

1. Orange portal starts to enter the blue one with its lower edge.

2. Since it went through the middle of a blue portal, it must exit through the middle of itself.
Notice that the filled-in orange square is now facing the hollow orange one- just like it was
facing the hollow blue square before entering.
The lower horizontal arrow shows that the middle of the orange portal is getting nearer and nearer to the blue one- so not only the exiting part of the orange portal is getting longer, but it is approaching the blue one at the same time (like the two upper arrows show).

3. Here we see that the halves of the orange and a blue portal are in the same place.
Since the filled-in end of a portal is still approaching the blue portal, it will now enter it for the second time, while being parallel to it. The moment this half of the orange portal exits itself, it will start to get longer.

4. Since the orange filled-in end of a portal entered the blue one while being parallel to it, it will also exit the other portal (that is: itself) while being parallel to it. Both parts of the orange portal must obviously have the length of 1 entire orange portal- that is why the exiting filled-in end is longer than the hollow end.
The upper arrow shows that the filled-in end of the orange portal is both getting longer, and going farther from the other end, while still being parallel to it.

5. The orange portal now almost entirely went through; its filled-in end is approaching the edge of the blue portal.

6. Orange portal finally exited itself and visibly rotated by 180 degrees.
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anonymous's avatar
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Sabrina333's avatar
You are a genius. You have unbucked so many brains now.
dziadek1990's avatar
dziadek1990Hobbyist Writer
Check difficulties of math tests in universities and you'll say otherwise. =P
npcw's avatar
makes sense, one problem, wouldn't the portal collapse because of its endless loop? making it impossible to enter, rendering it useless? (or ripping apart anything that does?
dziadek1990's avatar
dziadek1990Hobbyist Writer
Not endless. Overall the portal goes through itself twice. Even if, say, two portals collided with eachother while parallel to eachother from the very start and would keep entering eachother infinite amount of times, since upon collision they would be in the same location, the result would just be them both teleporting to the spot they are already in, ie. staying fixed in place.

This experiment just analyzes the situation from the geometrical/topological point of view, not physics. With portals involved, it would be easy to create a black hole by crushing an object between two portals, but since I don't include the mass of objects in this experiment, nothing similiar to what you are talking about will occur.
excitestudios's avatar
excitestudiosHobbyist Traditional Artist

IT HURTS TO BAD!!! :tears:
xXSpiritKeeperXx's avatar
xXSpiritKeeperXxHobbyist General Artist
THIS is thinking with portals.
dziadek1990's avatar
dziadek1990Hobbyist Writer
I also have done many thought experiments how would they work if they made you travel in time, rather than just space. I love the concept of spacetime and am a time travel geek.
xXSpiritKeeperXx's avatar
xXSpiritKeeperXxHobbyist General Artist
Aww yeah, sounds awesome! I'd love to see them! :D
KillMarioLoveBowser's avatar
KillMarioLoveBowserStudent Writer
Mother of portals! :iconmother-of-godplz:
It's Portalception!
creepcrab's avatar
you know what would happen? same when you try to divide by zero XD

epicabsol's avatar
epicabsolHobbyist Digital Artist
Head.... hurts...
Lenitas's avatar

(this is awesome.)
cygaj's avatar
Już cię lubię.
valleyviolet's avatar
My brain hurts.
Testsubject276's avatar
Testsubject276Student Digital Artist
Evilmisssingno000's avatar
Evilmisssingno000Hobbyist General Artist
It's not a paradox since it does make sense
Testsubject276's avatar
Testsubject276Student Digital Artist
Too late. My head exploded....
whitetower-exe's avatar
whitetower-exeStudent Digital Artist

anonymous's avatar
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