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Physical 3x3x3x3 hypercube and other physical 4d twisty puzzles [video]

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Re: Physical 3x3x3x3 hypercube and other physical 4d twisty puzzles [video]

#4
Unbelievable. I used to be a collector of twisty puzzles and there was quite a few levels of challenging puzzles beyond my ability, but seeing this is just astounding! I only have barely a clue what each of the moves are doing but it makes me smile knowing someone cared enough to make this. Science has gone too far

Re: Physical 3x3x3x3 hypercube and other physical 4d twisty puzzles [video]

#9
post #8

I don't understand how that's a 3x3x3x3. While there are some 3x3 elements, there are only 2 layers and 2 side by side. What am I missing?

He starts out showing a 2x2x2x2 and doesn't get to the 3x3x3x3 until just after the 10 minute mark.

Re: Physical 3x3x3x3 hypercube and other physical 4d twisty puzzles [video]

#10
I trust the math. I trust the manipulator.

But it drives home the reason why I parted ways with advanced math. There just came a point when the math no longer resonated with the natural world that I was comfortable living in.

Imaginary (and complex) numbers were the first real schism where my mind repelled the very idea.

Nonetheless, decades later, I would be talking with a friend who is much smarter than me. We were talking about the lossy nature of converting audio from the time domain to the frequency domain and back. I understood that phase information was lost in the translation (I also thought it was curious that the human brain seemed to be phase-agnostic and so could not perceive the difference when audio was round-tripped through the frequency domain).

"Oh," he said, "when you do a Fast Fourier transform to move audio into the frequency domain the phase information is represented by the imaginary part of a complex number."

Wait, what? So complex numbers have a real-world analog in constructing an FFT — a "real" algorithm that does real work?

I see now that the really smart people just understand the natural world much better than I do — or perhaps see it differently than I do.

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