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Timeline for Fair but irregular polyhedral dice

Current License: CC BY-SA 3.0

27 events
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Feb 15 at 11:18 comment added Maxxer My first intuition is that full symmetry group acting transivly on sides should be sufficient condition.
May 27, 2017 at 13:29 comment added YCor @JosephO'Rourke Thanks! I actually looked into online Cambridge and Webster dictionary and found nothing at "die", but a reference to "die" at "dice". Then at Oxford dictionary there is (en.oxforddictionaries.com/definition/die) en entry "die" in this sense: "Singular form of dice (...) In modern standard English, the singular die (rather than dice) is uncommon. Dice is used for both the singular and the plural"
May 27, 2017 at 12:08 comment added Joseph O'Rourke @YCor: "dice" is the plural. Each cuboid is a "die," the singular. Thus we have "the die is cast," meaning the roll of fate has happened and events cannot be changed.
May 27, 2017 at 11:07 comment added YCor I'm not native English speaker; is there any reason several users write "die" / "fair die" instead of "dice"? Is it a pun? slang? or just a typo?
S May 27, 2017 at 6:04 history suggested Martin Sleziak CC BY-SA 3.0
Replaced picture by imgur link (which should be more stable); removed deprecated (geometry) tag
May 27, 2017 at 5:54 review Suggested edits
S May 27, 2017 at 6:04
Mar 10, 2017 at 9:42 history edited CommunityBot
replaced http://people.csail.mit.edu/ with https://people.csail.mit.edu/
Dec 9, 2011 at 21:27 answer added Valerio Capraro timeline score: 3
Dec 9, 2011 at 13:23 history edited Joseph O'Rourke CC BY-SA 3.0
Moved image to another server.
Dec 9, 2011 at 6:45 answer added Scott Sherman timeline score: 9
Jan 1, 2011 at 2:10 vote accept Joseph O'Rourke
Dec 15, 2010 at 23:05 comment added Joseph O'Rourke @Michael: Given Bill Th.'s latest comments, the "obviously fair" examples may be of considerable interest!
Dec 15, 2010 at 3:10 answer added Bill Thurston timeline score: 30
Dec 8, 2010 at 23:30 answer added Robert Connelly timeline score: 14
Nov 20, 2010 at 21:31 comment added Michael Hardy I've seen polyhedra that are obviously fair without any reference to the intermediate value theorem. But if you want a right circular cylinder that's "fair", the intermediate value theorem would seem to provide a nonconstructive existence proof. A constructive proof might be difficult, I would guess.
Nov 20, 2010 at 20:38 answer added sleepless in beantown timeline score: 4
Nov 20, 2010 at 15:23 comment added Joseph O'Rourke @Guillaume: Excellent point that even 2D seems interesting (and difficult!).
Nov 20, 2010 at 15:13 answer added Joseph O'Rourke timeline score: 11
Nov 20, 2010 at 13:03 answer added Matt Fayers timeline score: 29
Nov 20, 2010 at 3:25 answer added sleepless in beantown timeline score: 3
Nov 20, 2010 at 2:28 comment added J. M. isn't a mathematician Also if the die bounces after being thrown...
Nov 20, 2010 at 0:51 comment added Tom Goodwillie Without symmetry the answer would seem to have to depend on physical assumptions about friction and about how hard the die is thrown and how fast it is spinning.
Nov 20, 2010 at 0:30 comment added Guillaume Brunerie @J.M. I don’t think so, if you take a bipyramidal die with many faces, it will be fair (because it is isohedral), but the dihedral angles will be very close to 180 degrees.
Nov 19, 2010 at 23:30 comment added J. M. isn't a mathematician I'd speculate that the dihedral angles can't be too "near" (making this rigorous, I'll leave to other people) a straight (180 degrees) angle; it might become easy to cheat with the die by blowing on it (or a subtle nudge, or somesuch) to show a possibly different face.
Nov 19, 2010 at 22:59 comment added Guillaume Brunerie Even the two dimensional case seems interesting, one can perhaps compute explicitely the probability of each face of a given convex polygon. But I don’t know how to model the shock of the die with the floor.
Nov 19, 2010 at 22:38 comment added Steve Huntsman Notwithstanding the "Fair dice" paper, if the moments of inertia are unequal it's hard to see how you can get physical randomness of outcomes in a really strong sense: blog.eqnets.com/2009/08/24/dynamical-bias-in-the-dice-roll
Nov 19, 2010 at 22:12 history asked Joseph O'Rourke CC BY-SA 2.5