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Can water solve a maze? [video]

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Re: Can water solve a maze? [video]

#101

The thing that I found most interesting was actually the little side discussion about all mazes being two pieces. Something that I had never considered, but seems fairly self evident (assuming only one path exists through the maze). Also makes me wonder what a proof would look like.

This reminds me of trying to imagine a "Flatland" creature's biology; you can't really have one with a digestive tract.

Re: Can water solve a maze? [video]

#102
post #49

Not sure if mazes are np complete but if so could we map other problems into maze designs and the water can solve problems for us?

They are not NP at all. A perfect maze (with one solution) as a connectivity graph is a tree. Finding the path through a tree can be done by DFS in linear O(N) time.

all P problems are in NP \pedantic

Re: Can water solve a maze? [video]

#103

Earlier quoted context omitted.

AFAIK this would also work with an incompressible fluid like water if you started the maze fully filled than add a sink at the exit and a source at the entrance. You wouldn't have any bubbles in that case and the current would flow along the solution.

It would be interesting to see what would happen to a fully filled maze if, once you got a steady continuous flow at the entrance and exit, you injected some dye into the water at the maze entrance.

It would have been even more interesting if this was not in the linked video!

Re: Can water solve a maze? [video]

#104
post #42

Earlier quoted context omitted.

Mostly, but surface tension in aggregate is meaningful. Surface tension is doing two things, first it’s contributing to back pressure several times in the same way it’s just barely keeping water from over topping. Secondly it’s taking up volume in air pockets thus increasing the pressure of those pockets. So, if he added soap to reduce surface tension the tank wouldn’t empty but it would end up lower. My guess is rou…

What's great about this video and the discussion is that something as familiar as water can have new and non intuitive things to learn about it. Are there any other examples of common things that have non obvious behaviour from every day experience?

Sounds like great AskHN material to me, especially if you allow computers-related answers : - )

Re: Can water solve a maze? [video]

#105

The thing that I found most interesting was actually the little side discussion about all mazes being two pieces. Something that I had never considered, but seems fairly self evident (assuming only one path exists through the maze). Also makes me wonder what a proof would look like.

This reminds me of trying to imagine a "Flatland" creature's biology; you can't really have one with a digestive tract.

You could have, the creature would just need a pair of zippers that unzip and zip the digestive tract as materials pass through, a bit like RNA polymerase unwinds and rewinds a strand of DNA. The zipper's teeth could act as conduits for the nervous and circulatory systems.

Re: Can water solve a maze? [video]

#106
post #99

Reminded me: https://en.m.wikipedia.org/wiki/Water_integrator The Water Integrator (Russian: Гидравлический интегратор Gidravlicheskiy integrator) was an early analog computer built in the Soviet Union in 1936 by Vladimir Sergeevich Lukyanov. It functioned by careful manipulation of water through a room full of interconnected pipes and pumps. The water level in various chambers (with precision to fractions of a milli…

When I first started learning EE I conceptualized it with water. Ie voltage / potential is a higher water level vs else where. But this takes it to a whole new level, impressive!

Re: Can water solve a maze? [video]

#108
post #99

Reminded me: https://en.m.wikipedia.org/wiki/Water_integrator The Water Integrator (Russian: Гидравлический интегратор Gidravlicheskiy integrator) was an early analog computer built in the Soviet Union in 1936 by Vladimir Sergeevich Lukyanov. It functioned by careful manipulation of water through a room full of interconnected pipes and pumps. The water level in various chambers (with precision to fractions of a milli…

When I first started learning EE I conceptualized it with water. Ie voltage / potential is a higher water level vs else where. But this takes it to a whole new level, impressive!

If you search the web (or only Youtube), there are even digital water computers out there.

Re: Can water solve a maze? [video]

#110

Earlier quoted context omitted.

The creator remains without a creation. The notion that most schools of thought have is, the creator is unborn and born at the same time and has always existed. Creator does not have a point of creation, not even death because those rules only apply to the materialistic universe.

That's quite a cop out. Excuse me if I don't take your word for it.

It isn't a cop out because the creator in the conclusion of this type of argument (e.g. Aquinas' third way) is not just another contingent being like other things, but rather a being whose existence is necessary in itself.
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