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Can water solve a maze? [video]

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Re: Can water solve a maze? [video]

#32

For sufficiently large mazes it must get harder to push the water through. Water can't solve a Tesla valve. ( https://en.wikipedia.org/wiki/Tesla_valve )

Yes, water can solve a Tesla valve:

> Steady flow experiments, including with the original design, however, show smaller ratios of the two resistances* in the range of 2 to 4.[6] It has also been shown that the device works better with pulsatile flows.[6]

*Ratio of resistance to water flowing "forward" vs. "backward" through the Tesla valve.

Though if you stretch things far enough - say, a thick layer of "waterproof" clay - your statement is correct for most purposes.

Re: Can water solve a maze? [video]

#33

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.

[deleted]

Re: Can water solve a maze? [video]

#34

A computer is a computer, and our universe is a computer. So, it's possible we're living in a simulation but not one that was intentionally constructed by a higher life form, but rather, a simulation that emerged from nature (e.g. electrons whizzing along the surface of silica rock on a desolate planet). Our universe could recursively be computers all the way down.

The simulation theory simply postpones the hard problem of consciousness. It's like a magician trick, pulling wool over the eyes, moving your attention away from the real problem long enough, so that you stop thinking about it.

How so? By “hard problem” do you mean defining what consciousness is?

Re: Can water solve a maze? [video]

#35
So it's basically A* with higher scores when going towards gravity, very cool.

Another physics problem analogue I really like is the problem of fastest travel from point A to point B when you have to cross a river. One approach to solve is is to treat it as a minimization problem by writing down everything, another one is to realize light beams have already solved this problem for you, and the problem becomes much simpler when your river entry angle α and swimming angle β have to satisfy (sin α)/v_walking = (sin β)/v_swimming and the fastest path is the one which just happens to satisfy this angle constraint

Re: Can water solve a maze? [video]

#37
Very nice.

I think that the explanation given for why the water stops flowing [1] is wrong. It has likely less to do with the surface tension "on the lip" (see video) and more with the fact that that all air bubbles in the maze become pressurized and their cumulative pressure is enough to push back on the water trying to get into the maze and prevent it from flowing in.

I do agree though that it's a rather unexpected behavior.

[1] https://www.youtube.com/watch?v=81ebWToAnvA&t=370

Re: Can water solve a maze? [video]

#38

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.

You can make a maze with only one path (other than paths that double back on themselves), but has three pieces: https://i.imgur.io/R4j6TH3_d.png

I think this is basically a flaw in the intuitive definition (or maybe only my intuitive definition) of "doubling back".

Re: Can water solve a maze? [video]

#39
post #22
post #14

Earlier quoted context omitted.

If it is a simulation, what is it simulating? There would have to be a "real" reference to compare against?

I don't think a simulation needs to simulate anything real. Eg. if I have a program that runs Conway's game of life, that would be also be a simulation, but there's nothing "real" it references against. In other words, the universe simulating ours might work completely differently, and some beings there are just testing how different laws of physics (i.e. ours) work out.

some beings there are just testing how different laws of physics (i.e. ours) work out

Or there is a practical use like energy extraction. Or they live (if that even applies) in a universe that generates what our closest concepts of are e.g. time and energy, and they have to spend them massively in simulations to survive. Or their laws of nature tend to overcommunicate (dilute) them into a single being, so they simulate everything we see for islands of “themselves” to remain distinct. They split themselves endlessly with perception because that’s the trick in their situation.

One of my nightmares is to wake up from this and realize you woken up from a mild depression into a horror of a true existence, and this isn’t even a final level. Makes sense, since if god is infinite, why shouldn’t he be infinitely suffering. Why would he (you) create all this if not to escape from null-reality.

Re: Can water solve a maze? [video]

#40

Very nice. I think that the explanation given for why the water stops flowing [1] is wrong. It has likely less to do with the surface tension "on the lip" (see video) and more with the fact that that all air bubbles in the maze become pressurized and their cumulative pressure is enough to push back on the water trying to get into the maze and prevent it from flowing in. I do agree though that it's a rather unexpected…

It shouldn't be, because every bit of upwards pressure towards the exit is compensated by the same amount of downwards pressure on the path before. I'm surprised there is that much static resistance in the maze.
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