## Dark room problem

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myrcutio
Posts: 44
Joined: Wed Dec 30, 2009 7:28 pm UTC

### Dark room problem

I have a problem, and I suspect it exists somewhere else under another name, but I thought I'd lay it out as an analogy and let someone smarter than I tell me if there is a solution. Here's the setup:

There's a party, and it's really packed. Wall to wall bodies, but there's enough room for one or two people to move at a time. There's only one door, and any one person can get through at a time but if they all rushed for it it would take a long time to clear out. The circuit for the lights goes out and everyone's left standing in the dark. They all know someone has to go to the basement to flip the breaker, but if everyone tries to go at once it'll just make things worse.

Here's the question:
How can any one person in the room know, without seeing or talking to anyone else, that they are the one person who should go to the basement and flip the switch?
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Posts: 3072
Joined: Mon Oct 22, 2007 5:28 pm UTC
Location: Beaming you up

### Re: Dark room problem

They'd solve it by seeing that they were the closest to the door. Since this sounds like a metaphor for networking, I'm going to step out of the metaphor to say that this problem becomes easier when each node has access to not just the communications cost of itself to each neighbor, but also the costs of neighbors to neighbors of neighbors. The basement would then be just another node, and your solution is "if I can see the basement and I am the lowest cost to go to the basement, pick myself".
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Bloopy
Posts: 215
Joined: Wed May 04, 2011 9:16 am UTC
Location: New Zealand

### Re: Dark room problem

Each person would need to be conscious of who or what was nearby, so it's like a swarm robotics problem. Under what conditions does a robot break formation and carry out a solo mission? When the lights go out, the person who remembers being in easiest reach of the door goes for it.

Moose Anus
Posts: 420
Joined: Fri Oct 14, 2011 10:12 pm UTC

### Re: Dark room problem

What do you mean by "should"? Should really drunk people not do it? Should only the building owner do it because they know where the circuit breakers are?

They might just talk about it to figure it out. Like, "Hey, I know where the circuit breakers are. Let me through!"

Nem
Posts: 336
Joined: Fri Aug 14, 2009 12:19 pm UTC

### Re: Dark room problem

myrcutio wrote:I have a problem, and I suspect it exists somewhere else under another name, but I thought I'd lay it out as an analogy and let someone smarter than I tell me if there is a solution. Here's the setup:

There's a party, and it's really packed. Wall to wall bodies, but there's enough room for one or two people to move at a time. There's only one door, and any one person can get through at a time but if they all rushed for it it would take a long time to clear out. The circuit for the lights goes out and everyone's left standing in the dark. They all know someone has to go to the basement to flip the breaker, but if everyone tries to go at once it'll just make things worse.

Here's the question:
How can any one person in the room know, without seeing or talking to anyone else, that they are the one person who should go to the basement and flip the switch?

Everyone should just go. If they don't get out easily then they weren't closest and can abort. The objective isn't to clear the room, it's for one person to get to the basement fastest - whoever's closest will get there first.