--0016368e240bc5f2a70494126633
Content-Type: text/plain; charset=ISO-8859-1
I was also thinking some yesterday about this thread between Andrey and
Nan. Puzzles with infinite-sided cells seemed understandable (now that
Andrey has shown the way!), but I had been having trouble wrapping my head
around puzzles with infinite-sided vertex figures. So although I could see
the {infinity,3} puzzle Andrey suggested would be a nice addition to
MagicTile (even if the programming might be difficult), thinking about
{3,infinity} was confounding. How would *that* behave?
I went back to Don's pictures that Melinda emailed about, and looked at the
two views he has of the {3,infinity} tiling (the dual to the {infinity,3}).
What is interesting is that the cells are "ideal triangles" - all the
cell vertices lie at infinity, on the boundary of the disk. They are
infinite in extent *in multiple directions* (though not infinite in area).
So then I thought about how one would twist one of these cells, and
concluded that it would not be possible to (isometrically) twist a cell
without it overlapping other parts of the puzzle, since the vertices will
remain on the disk boundary through the motion. So if you want to have a
puzzle with an infinite vertex figure, you'll be forced to have it behave in
an impossiball-like fashion (at least for 2D puzzles).
Furthermore, the slicing becomes degenerate for a {3,infinity} puzzle unless
you want make some modifications to the previous MagicTile generalization.
If you stick to circle slices (or sphere slices in H3), the only slicing
circle encompassing the entire cell is the disk boundary itself, and a twist
using that would be a rotation of the entire space. It would not permute
anything. One option would be to have slicing circles which did not contain
the entire cell though, and this could lead to some interesting puzzles.
That seems like the only good way forward to me actually.
I think the {4,4,4} situation will have some similarities to these
thoughts. Each cell in the {6,3,3} tiling only has one ideal point at
infinity, but the cells in the {4,4,4} tiling will have an infinite number
of ideal points. It seems the result is that any twist (which moves all the
material in a cell) will lead to overlapping material in the puzzle (?, I'm
not 100%). The slicing certainly suffers from the same issues described
above. It is the normal problems of puzzles without simplex vertex figures
multiplied by a gazillion!
Well, I could probably spew more, but I'll stop in the hope that this
doesn't all just sound like gibberish. I realize that if one
didn't have some familiarity with the disk/ball models of hyperbolic spaces,
it probably would. (The first six chapters of Visual Complex
Analysis
are
awesome for learning about these models btw.)
Roice
On Thu, Oct 28, 2010 at 1:28 PM, Andrey
> I'm not sure. If you take section of {4,4,4} with the plane going through
> the middle of the edge (and ortogonal to it), you'll get {infinity,4}
> tiling. It's difficult but not impossible to draw. And after some work with
> it (enumeration of areas, periodic colorings, etc) we can try to expand it
> to H3 space.
>
> {infinity, infinity} is very easy - in half-plane model. You draw series of
> half-circles (n,1/2), then take each of them and build the inversion of the
> drawing with respect to this circle. Result will look like fractal object
> based on continued fractions (with positive and negative quotients)...
> something like that. I never tried to draw it.
>
> Andrey
>
On Thu, Oct 28, 2010 at 1:01 PM, schuma
> I believe the first step to understand {4,4,4} is to understand {infinity,
> infinity} in the hyperbolic plane. What does {infinity, infinity} look like
> and how to draw it? It seems like no matter how you project it, you need to
> truncate not only each polygon and each vertex. After truncation, the
> picture would always look like an incomplete construction site.
>
> Nan
>
--0016368e240bc5f2a70494126633
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
d Nan.=A0 Puzzles with infinite-sided cells seemed understandable (now that=
Andrey has shown the way!), but I had been having trouble wrapping my head=
around puzzles with infinite-sided vertex figures.=A0 So although I could =
see the {infinity,3} puzzle Andrey suggested would be a nice addition to Ma=
gicTile (even if the programming might be difficult),=A0thinking=A0about {3=
,infinity} was confounding.=A0 How would that behave?
ed at the two views he has of the {3,infinity} tiling (the dual to the {inf=
inity,3}).=A0 What is interesting is that the cells are "ideal triangl=
es" - all the cell=A0vertices lie at infinity, on the boundary of the =
disk.=A0 They are infinite in extent in multiple directions> (though not infinite in area).=A0 So then I thought about how one would t=
wist one of these cells, and concluded that it would not be possible to (is=
ometrically) twist a cell without it overlapping other parts of the puzzle,=
since the vertices will remain on the disk boundary through the motion.=A0=
So if you want to have a puzzle with an infinite vertex figure, you'll=
be forced to have it=A0behave in an impossiball-like fashion (at least for=
2D puzzles).
e unless you want make some modifications to the previous MagicTile general=
ization.=A0 If you stick to circle slices (or sphere slices in H3), the onl=
y slicing circle encompassing the entire cell is the disk boundary itself, =
and a twist using that would be a rotation of the entire space.=A0 It would=
not permute anything.=A0 One option would be to have slicing circles which=
did not contain the entire cell though, and this could lead to some intere=
sting puzzles.=A0 That seems like the only good way forward to me actually.=
ughts.=A0 Each cell in the {6,3,3} tiling only has one ideal point at infin=
ity, but the cells in the {4,4,4} tiling will have an infinite number of id=
eal points.=A0 It seems the result is that any twist (which moves all the m=
aterial in a cell) will lead to overlapping material in the puzzle (?, I=
9;m not 100%).=A0 The slicing certainly suffers from the same issues descri=
bed above.=A0 It is the normal problems of puzzles without simplex vertex f=
igures multiplied by a gazillion!
=A0this doesn't all just sound like gibberish.=A0 I realize that if=A0o=
ne didn't=A0have=A0some=A0familiarity with the disk/ball models of hype=
rbolic spaces, it=A0probably would. (The first six chapters of ttp://www.amazon.com/gp/product/0198534469?ie=3DUTF8&tag=3Dgravit-20&am=
p;linkCode=3Das2&camp=3D1789&creative=3D390957&creativeASIN=3D0=
198534469">Visual Complex Analysis=A0are awesome for learning about the=
se models btw.)
=A0
dding-left:1ex" class=3D"gmail_quote">I'm not sure. If you take section=
of {4,4,4} with the plane going through the middle of the edge (and ortogo=
nal to it), you'll get {infinity,4} tiling. It's difficult but not =
impossible to draw. And after some work with it (enumeration of areas, peri=
odic colorings, etc) we can try to expand it to H3 space.
{infinity, infinity} is very easy - in half-plane model. You draw serie=
s of half-circles (n,1/2), then take each of them and build the inversion o=
f the drawing with respect to this circle. Result will look like fractal ob=
ject based on continued fractions (with positive and negative quotients)...=
something like that. I never tried to draw it.
Andrey
t; wrote:
dding-left:1ex" class=3D"gmail_quote">I believe the first step to understan=
d {4,4,4} is to understand {infinity, infinity} in the hyperbolic plane. Wh=
at does {infinity, infinity} look like and how to draw it? It seems like no=
matter how you project it, you need to truncate not only each polygon and =
each vertex. After truncation, the picture would always look like an incomp=
lete construction site.
Nan
--0016368e240bc5f2a70494126633--
At first I thought about {3,infinity} as a puzzle with material overlappi=
ng twists. So each cell has 7 stickers (one 1C, three 2C and three infinite=
-C). Once you get periodic coloring of the puzzle (and there is a lot of th=
em), vertex pieces will look as a periodic sequence of colors. For example,=
for 8-color scheme you'll get 6 vertex pieces with colors (0132), (0264), =
(0451), (4675), (1573) and (2376). Actually, it will be {3,4} spherical puz=
zle. Also {3,infinity} will include {3,6}, {3,7} and all other similar obje=
cts :) BTW, {infinity,3} gives easy way to find coloring schemes for {N,3}.=
For example, there is 36-colors for {9,3}, but I'm not sure about 12- or 1=
8-colors.
Alterantive way is to use deep-cut of {3,infinity} with movable centers o=
f adjacent faces but unmovable (and non-rotating) vertex pieces. Or enable =
rotation of oricycles containing vertecies as well, but it will be differen=
t puzzle... What is {3,infinity} rectified? Something strange (like (3,infi=
nity,3,infinity) polyhedron).
For {4,4,4} (that can be built from the checkerboard coloring of {4,4,3} =
by expanding of only black cells) I also think about twists with material o=
verlapping. Vertex pieces there will have periodic 2D ({4,4}) coloring, and=
it will be difficult to describe their "position and orientation".
Slicing of {4,4,4} without overlapping should be very difficult. But fixe=
d positions and orientations of vertecies may help a lot - if "centers" of =
cells will be movable (it's a joke, of course: these centers are ideal poin=
ts as well).
Too many things to do and absolutely no time for them... I want hyperboli=
c metrics of the time!
Good luck!
Andrey
--- In 4D_Cubing@yahoogroups.com, Roice Nelson
>
> I was also thinking some yesterday about this thread between Andrey and
> Nan. Puzzles with infinite-sided cells seemed understandable (now that
> Andrey has shown the way!), but I had been having trouble wrapping my hea=
d
> around puzzles with infinite-sided vertex figures. So although I could s=
ee
> the {infinity,3} puzzle Andrey suggested would be a nice addition to
> MagicTile (even if the programming might be difficult), thinking about
> {3,infinity} was confounding. How would *that* behave?
>=20
> I went back to Don's pictures that Melinda emailed about, and looked at t=
he
> two views he has of the {3,infinity} tiling (the dual to the {infinity,3}=
).
> What is interesting is that the cells are "ideal triangles" - all the
> cell vertices lie at infinity, on the boundary of the disk. They are
> infinite in extent *in multiple directions* (though not infinite in area)=
.
> So then I thought about how one would twist one of these cells, and
> concluded that it would not be possible to (isometrically) twist a cell
> without it overlapping other parts of the puzzle, since the vertices will
> remain on the disk boundary through the motion. So if you want to have a
> puzzle with an infinite vertex figure, you'll be forced to have it behave=
in
> an impossiball-like fashion (at least for 2D puzzles).
>=20
> Furthermore, the slicing becomes degenerate for a {3,infinity} puzzle unl=
ess
> you want make some modifications to the previous MagicTile generalization=
.
> If you stick to circle slices (or sphere slices in H3), the only slicing
> circle encompassing the entire cell is the disk boundary itself, and a tw=
ist
> using that would be a rotation of the entire space. It would not permute
> anything. One option would be to have slicing circles which did not cont=
ain
> the entire cell though, and this could lead to some interesting puzzles.
> That seems like the only good way forward to me actually.
>=20
> I think the {4,4,4} situation will have some similarities to these
> thoughts. Each cell in the {6,3,3} tiling only has one ideal point at
> infinity, but the cells in the {4,4,4} tiling will have an infinite numbe=
r
> of ideal points. It seems the result is that any twist (which moves all =
the
> material in a cell) will lead to overlapping material in the puzzle (?, I=
'm
> not 100%). The slicing certainly suffers from the same issues described
> above. It is the normal problems of puzzles without simplex vertex figur=
es
> multiplied by a gazillion!
>=20
> Well, I could probably spew more, but I'll stop in the hope that this
> doesn't all just sound like gibberish. I realize that if one
> didn't have some familiarity with the disk/ball models of hyperbolic spac=
es,
> it probably would. (The first six chapters of Visual Complex
> Analysis
9>
> are
> awesome for learning about these models btw.)
>=20
> Roice
>=20
--001636c5c2f44c1e170494279fcc
Content-Type: text/plain; charset=ISO-8859-1
On Wed, Nov 3, 2010 at 2:23 AM, Andrey
> What is {3,infinity} rectified? Something strange (like
> (3,infinity,3,infinity) polyhedron).
You can see the rectified {3,infinity} on Don's tessellation
page
The rectified tilings are the ones with a tessellation value of 2. Two
views of the rectified {3,infinity} tiling are
here
here
(the
blue lines those pictures), and you were right. The tiling is made of
4-gons with two ideal vertices, and three tiles meeting at both of the other
two vertices.
Roice
--001636c5c2f44c1e170494279fcc
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
oo.com> wrote:
; PADDING-LEFT: 1ex" class=3D"gmail_quote">=A0What is {3,infinity} rectifie=
d? Something strange (like (3,infinity,3,infinity) polyhedron).>
rectified tilings are the ones with a tessellation value of 2.=A0 Two view=
s of the rectified {3,infinity} tiling are ~hatch/HyperbolicTesselations/inf_3_otherview_trunc2_512x512.gif">here =
and nc2_512x512.gif">here=A0(the blue lines those pictures), and you were r=
ight.=A0 The tiling is made of 4-gons with two ideal vertices, and three ti=
les meeting at both of the other two vertices.
--001636c5c2f44c1e170494279fcc--
--00151747bcb4ea0a31049427d1bf
Content-Type: text/plain; charset=ISO-8859-1
Please excuse the typo. The rectified tilings are the ones with a
*truncation* value of 2.
Roice
On Wed, Nov 3, 2010 at 10:23 AM, Roice Nelson
>
> On Wed, Nov 3, 2010 at 2:23 AM, Andrey
>
>> What is {3,infinity} rectified? Something strange (like
>> (3,infinity,3,infinity) polyhedron).
>
>
> You can see the rectified {3,infinity} on Don's tessellation page
> The rectified tilings are the ones with a tessellation value of 2. Two
> views of the rectified {3,infinity} tiling are here
> here
> blue lines those pictures), and you were right. The tiling is made of
> 4-gons with two ideal vertices, and three tiles meeting at both of the other
> two vertices.
>
> Roice
>
--00151747bcb4ea0a31049427d1bf
Content-Type: text/html; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
truncation* value of 2.pan dir=3D"ltr"><roice3@gmail.com>> wrote:
; PADDING-LEFT: 1ex" class=3D"gmail_quote">
<andreyast=
relin@yahoo.com> wrote:
; PADDING-LEFT: 1ex" class=3D"gmail_quote">=A0What is {3,infinity} rectifie=
d? Something strange (like (3,infinity,3,infinity) polyhedron).>
n page.=A0 The rectified tilings are the ones with a tessellation value=
of 2.=A0 Two views of the rectified {3,infinity} tiling are p://www.plunk.org/~hatch/HyperbolicTesselations/inf_3_otherview_trunc2_512x=
512.gif" target=3D"_blank">here and tch/HyperbolicTesselations/inf_3_trunc2_512x512.gif" target=3D"_blank">here=
=A0(the blue lines those pictures), and you were right.=A0 The tiling i=
s made of 4-gons with two ideal vertices, and three tiles meeting at both o=
f the other two vertices.
--00151747bcb4ea0a31049427d1bf--