A single portal into all the different rooms might work if you are ok with your continuous room-choosing mechanism having a probability of zero to get you into your chosen room.
Not a problem as long as you take everying with you since the probability of hitting some empty room is of course still one.
Yes, since I have hands to feel the door. Hands which, incidentally, are able to help me count things they touch :)
Okay, automatic doors with perfectly precise sensors based on shifts in gravity.
A single portal into all the different rooms might work if you are ok with your continuous room-choosing mechanism having a probability of zero to get you into your chosen room. Not a problem as long as you take everying with you since the probability of hitting some empty room is of course still one.
What about upon entering a room a new normal door is then constructed, allowing re-entry?