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A new pyramid-like shape always lands the same side up

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584 points robinhouston | 5 comments | 25 Jun 25 20:01 UTC | HN request time: 0s | source
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ChuckMcM ◴[25 Jun 25 21:09 UTC] No.44381861[source]▶
Worst D-4 ever! But more seriously, I wonder how closely you could get to an non-uniform mass polyhedra which had 'knife edge' type balance. Which is to say;

1) Construct a polyhedra with uneven weight distribution which is stable on exactly two faces.

2) Make one of those faces much more stable than the other, so if it is on the limited stability face and disturbed, it will switch to the high stability face.

A structure like that would be useful as a tamper detector.

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ortusdux ◴[25 Jun 25 22:15 UTC] No.44382291[source]▶
You jest, but I knew a DND player with a dice addicting that loved showing off his D-1 Mobius strip dice - https://www.awesomedice.com/products/awd101?variant=45578687...

For some reason he did not like my suggestion that he get a #1 billard ball.

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1. lloeki ◴[26 Jun 25 08:03 UTC] No.44385232[source]▶
There's a link to a D2, where prior to clicking I was thinking "well that's a coin, right?" until I realised a coin is technically a (very biased) D3.
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2. stavros ◴[26 Jun 25 09:09 UTC] No.44385570[source]▶
Huh, now I'm curious, what did the D2 look like?
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3. riffraff ◴[26 Jun 25 09:32 UTC] No.44385681[source]▶
Lenticoidal, I guess? I.e. remove the outer face of the cilinder by making the faces curved
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4. stavros ◴[26 Jun 25 09:37 UTC] No.44385703{3}[source]▶
Yeah, that was my thought as well, but that's also basically a D3 with a really small third edge, in practice. I was wondering whether there's some clever shape that actually is a D2, though maybe that's a Möbius strip in reality.
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5. close04 ◴[26 Jun 25 10:02 UTC] No.44385841{4}[source]▶
> with a really small third edge

Doesn't every die have a bunch of edges or even vertices that aren't considered faces despite having a measurable width? As long as it's realistically impossible to land on that edge, I think it shouldn't count as a face.