fibrifold

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In mathematics, a fibrifold is (roughly) a fiber space whose fibers and base spaces are orbifolds. They were introduced by {{harvs | txt| last1=Conway | first1=John Horton | author1-link=John Horton Conway | last2=Delgado Friedrichs | first2=Olaf | last3=Huson | first3=Daniel H. | last4=Thurston | first4=William P. | author4-link=William Thurston | title=On three-dimensional space groups | url=http://www.emis.de/journals/BAG/vol.42/no.2/17.html | mr=1865535 | year=2001 | journal=Beiträge zur Algebra und Geometrie | issn=0138-4821 | volume=42 | issue=2 | pages=475–507}}, who introduced a system of notation for 3-dimensional fibrifolds and used this to assign names to the 219 affine space group types. 184 of these are considered reducible, and 35 irreducible.

Irreducible cubic space groups

File:35 cubic fibrifold groups.svgs in fibrifold and international index and Hermann–Mauguin notation. 212 and 213 are enantiomorphous pairs giving the same fibrifold notation.]]

The 35 irreducible space groups correspond to the cubic space group.

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|+ 35 irreducible space groups

8o:24:24o:24+:22:22o:22+:21o:2
8o44o4+22o2+1o
8o/44/44o/44+/42/42o/42+/41o/4
8−o8oo8+o4− −4−o4oo4+o4++2−o2oo2+o

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|+ 36 cubic groups

Class
Point group

!Hexoctahedral
*432 (m{{overline|3}}m)

!Hextetrahedral
*332 ({{overline|4}}3m)

!Gyroidal
432 (432)

!Diploidal
3*2 (m{{overline|3}})

!Tetartoidal
332 (23)

align=center

!bc lattice (I)

|8o:2 (Im{{overline|3}}m)

|4o:2 (I{{overline|4}}3m)

|8+o (I432)

|8−o (I{{overline|3}})

|4oo (I23)

align=center

!rowspan=2|nc lattice (P)

|4:2 (Pm{{overline|3}}m)

|rowspan=2|2o:2 (P{{overline|4}}3m)

|4−o (P432)

|4 (Pm{{overline|3}})

|rowspan=2|2o (P23)

align=center

|4+:2 (Pn{{overline|3}}m)

|4+ (P4232)

|4+o (Pn{{overline|3}})

align=center

!rowspan=2|fc lattice (F)

|2:2 (Fm{{overline|3}}m)

|rowspan=2|1o:2 (F{{overline|4}}3m)

|2−o (F432)

|2 (Fm{{overline|3}})

|rowspan=2|1o (F23)

align=center

|2+:2 (Fd{{overline|3}}m)

|2+ (F4132)

|2+o (Fd{{overline|3}})

align=center valign=top

!Other
lattice
groups

|8o (Pm{{overline|3}}n)
8oo (Pn{{overline|3}}n)
4− − (Fm{{overline|3}}c)
4++ (Fd{{overline|3}}c)

|4o (P{{overline|4}}3n)
2oo (F{{overline|4}}3c)

|

|

|

align=center valign=top

!Achiral
quarter
groups

|8o/4 (Ia{{overline|3}}d)

|4o/4 (I{{overline|4}}3d)

|4+/4 (I4132)
2+/4 (P4332,
P4132)

|2/4 (Pa{{overline|3}})
4/4 (Ia{{overline|3}})

|1o/4 (P213)
2o/4 (I213)

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|280px

|180px

|240px

valign=top

|8 primary hexoctahedral hextetrahedral lattices of the cubic space groups

|colspan=2|The fibrifold cubic subgroup structure shown is based on extending symmetry of the tetragonal disphenoid fundamental domain of space group 216, similar to the square

Irreducible group symbols (indexed 195−230) in Hermann–Mauguin notation, Fibrifold notation, geometric notation, and Coxeter notation:

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Class
(Orbifold point group)

!colspan=10| Space groups

align=center

!rowspan=5|Tetartoidal
23
(332)

!195

196197198199colspan=5| 
BGCOLOR="#ffe0e0" align=center

| P23

F23I23P213I213colspan=5| 
BGCOLOR="#e0e0ff" align=center

|2o

1o4oo1o/42o/4colspan=5| 
BGCOLOR="#ffffd0" align=center

| P{{overline|3}}.{{overline|3}}.{{overline|2}}

F{{overline|3}}.{{overline|3}}.{{overline|2}}I{{overline|3}}.{{overline|3}}.{{overline|2}}P{{overline|3}}.{{overline|3}}.{{overline|2}}1I{{overline|3}}.{{overline|3}}.{{overline|2}}1colspan=5| 
BGCOLOR="#e0ffe0" align=center

| [(4,3+,4,2+)]

[3[4]]+(4,3+,4,2+)colspan=5| 
align=center

!rowspan=5|Diploidal
{{overline|4}}3m
(3*2)

!200

201202203204205206colspan=3| 
BGCOLOR="#ffe0e0" align=center

| Pm{{overline|3}}

Pn{{overline|3}}Fm{{overline|3}}Fd{{overline|3}}I{{overline|3}}Pa{{overline|3}}Ia{{overline|3}}colspan=3| 
BGCOLOR="#e0e0ff" align=center

|4

4+o22+o8−o2/44/4colspan=3| 
BGCOLOR="#ffffd0" align=center

| P4{{overline|3}}

Pn4{{overline|3}}F4{{overline|3}}Fd4{{overline|3}}I4{{overline|3}}Pb4{{overline|3}}Ib4{{overline|3}}colspan=3| 
BGCOLOR="#e0ffe0" align=center

|[4,3+,4]

4,3+,4]+][4,(31,1)+][[3[4]+4,3+,4colspan=3| 
align=center

!rowspan=5|Gyroidal
432
(432)

!207

208209210211212213214colspan=2| 
BGCOLOR="#ffe0e0" align=center

| P432

P4232F432F4132I432P4332P4132I4132colspan=2| 
BGCOLOR="#e0e0ff" align=center4−o4+2−o2+8+ocolspan=2|2+/44+/4colspan=2| 
BGCOLOR="#ffffd0" align=center

| P{{overline|4}}.{{overline|3}}.{{overline|2}}

P{{overline|4}}2.{{overline|3}}.{{overline|2}}F{{overline|4}}.{{overline|3}}.{{overline|2}}F{{overline|4}}1.{{overline|3}}.{{overline|2}}I{{overline|4}}.{{overline|3}}.{{overline|2}}P{{overline|4}}3.{{overline|3}}.{{overline|2}}P{{overline|4}}1.{{overline|3}}.{{overline|2}}I{{overline|4}}1.{{overline|3}}.{{overline|2}}colspan=2| 
BGCOLOR="#e0ffe0" align=center

|[4,3,4]+

4,3,4]+]+[4,31,1]+[[3[4]+4,3,4+colspan=2|colspan=2| 
align=center

!rowspan=5|Hextetrahedral
{{overline|4}}3m
(*332)

!215

216217218219220colspan=4| 
BGCOLOR="#ffe0e0" align=center

| P{{overline|4}}3m

F{{overline|4}}3mI{{overline|4}}3mP{{overline|4}}3nF{{overline|4}}3cI{{overline|4}}3dcolspan=4| 
BGCOLOR="#e0e0ff" align=center2o:21o:24o:24o2oo4o/4colspan=4| 
BGCOLOR="#ffffd0" align=centerP33F33I33Pn3n3nFc3c3aId3d3dcolspan=4| 
BGCOLOR="#e0ffe0" align=center

|[(4,3,4,2+)]

[3[4]](4,3,4,2+)[[(4,3,4,2+)]+][+(4,{3),4}+]colspan=4| 
align=center

!rowspan=5|Hexoctahedral
m{{overline|3}}m
(*432)

!221

222223224225226227228229230
BGCOLOR="#ffe0e0" align=center

| Pm{{overline|3}}m

Pn{{overline|3}}nPm{{overline|3}}nPn{{overline|3}}mFm{{overline|3}}mFm{{overline|3}}cFd{{overline|3}}mFd{{overline|3}}cIm{{overline|3}}mIa{{overline|3}}d
BGCOLOR="#e0e0ff" align=center4:28oo8o4+:22:24−−2+:24++8o:28o/4
BGCOLOR="#ffffd0" align=centerP43Pn4n3nP4n3nPn43F43F4c3aFd4n3Fd4c3aI43Ib4d3d
BGCOLOR="#e0ffe0" align=center[4,3,4]4,3,4]+][(4+,2+)[3[4][4,31,1][4,(3,4)+]3[4]+(4,{3),4}+4,3,4

References

{{refbegin}}

  • {{Citation | last1=Conway | first1=John Horton | author1-link=John Horton Conway | last2=Delgado Friedrichs | first2=Olaf | last3=Huson | first3=Daniel H. | last4=Thurston | first4=William P. | author4-link=William Thurston | title=On three-dimensional space groups | url=http://www.emis.de/journals/BAG/vol.42/no.2/17.html | mr=1865535 | year=2001 | journal=Beiträge zur Algebra und Geometrie | issn=0138-4821 | volume=42 | issue=2 | pages=475–507}}
  • {{citation |first1=David |last1=Hestenes |first2=Jeremy W. |last2=Holt |title=The Crystallographic Space Groups in Geometric Algebra |journal=Journal of Mathematical Physics |volume=48 |issue=2 |pages=023514 |date=February 2007 |doi=10.1063/1.2426416 |bibcode=2007JMP....48b3514H |url=https://davidhestenes.net/geocalc/pdf/CrystalGA.pdf }}
  • {{citation |first1=John H. |last1=Conway |first2=Heidi |last2=Burgiel |first3=Chaim |last3=Goodman-Strauss |title=The Symmetries of Things |publisher=Taylor & Francis |year=2008 |isbn=978-1-56881-220-5 |zbl=1173.00001}}
  • {{citation |first=H.S.M. |last=Coxeter |chapter=Regular and Semi Regular Polytopes III |chapter-url=https://books.google.com/books?id=fUm5Mwfx8rAC&pg=PA313 |editor-first=F. Arthur |editor-last=Sherk |editor-first2=Peter |editor2-last=McMullen |editor3-first=Anthony C. |editor3-last=Thompson |editor4-first=Asia Ivić |display-editors=3 |editor4-last=Weiss |title=Kaleidoscopes: Selected Writings of H.S.M. Coxeter |publisher=Wiley |year=1995 |isbn=978-0-471-01003-6 |pages=[https://archive.org/details/kaleidoscopessel0000coxe/page/313 313–358] |zbl=0976.01023 |url=https://archive.org/details/kaleidoscopessel0000coxe/page/313 }}

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Category:Symmetry

Category:Finite groups

Category:Discrete groups

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