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:2 | 4−:2 | 4o:2 | 4+:2 | 2−:2 | 2o:2 | 2+:2 | 1o:2 | |||
8o | 4− | 4o | 4+ | 2− | 2o | 2+ | 1o | |||
8o/4 | 4−/4 | 4o/4 | 4+/4 | 2−/4 | 2o/4 | 2+/4 | 1o/4 | |||
8−o | 8oo | 8+o | 4− − | 4−o | 4oo | 4+o | 4++ | 2−o | 2oo | 2+o |
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|+ 36 cubic groups |
Class Point group !Hexoctahedral !Hextetrahedral !Gyroidal !Diploidal !Tetartoidal |
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!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) |
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!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) |
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|4+:2 (Pn{{overline|3}}m) |4+ (P4232) |4+o (Pn{{overline|3}}) |
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!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) |
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|2+:2 (Fd{{overline|3}}m) |2+ (F4132) |2+o (Fd{{overline|3}}) |
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!Other |8o (Pm{{overline|3}}n) |4o (P{{overline|4}}3n) | | | |
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!Achiral |8o/4 (Ia{{overline|3}}d) |4o/4 (I{{overline|4}}3d) |4+/4 (I4132) |2−/4 (Pa{{overline|3}}) |1o/4 (P213) |
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|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 | ||||||||||
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!rowspan=5|Tetartoidal !195 | 196 | 197 | 198 | 199 | colspan=5| | |||||
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| P23 | F23 | I23 | P213 | I213 | colspan=5| | |||||
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|2o | 1o | 4oo | 1o/4 | 2o/4 | colspan=5| | |||||
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| 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}}1 | I{{overline|3}}.{{overline|3}}.{{overline|2}}1 | colspan=5| | |||||
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| [(4,3+,4,2+)] | [3[4]]+ | (4,3+,4,2+) | colspan=5| | |||||||
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!rowspan=5|Diploidal !200 | 201 | 202 | 203 | 204 | 205 | 206 | colspan=3| | |||
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| Pm{{overline|3}} | Pn{{overline|3}} | Fm{{overline|3}} | Fd{{overline|3}} | I{{overline|3}} | Pa{{overline|3}} | Ia{{overline|3}} | colspan=3| | |||
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|4− | 4+o | 2− | 2+o | 8−o | 2−/4 | 4−/4 | colspan=3| | |||
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| P4{{overline|3}} | Pn4{{overline|3}} | F4{{overline|3}} | Fd4{{overline|3}} | I4{{overline|3}} | Pb4{{overline|3}} | Ib4{{overline|3}} | colspan=3| | |||
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|[4,3+,4] | [4,(31,1)+] | colspan=3| | ||||||||
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!rowspan=5|Gyroidal !207 | 208 | 209 | 210 | 211 | 212 | 213 | 214 | colspan=2| | ||
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| P432 | P4232 | F432 | F4132 | I432 | P4332 | P4132 | I4132 | colspan=2| | ||
BGCOLOR="#e0e0ff" align=center | 4−o | 4+ | 2−o | 2+ | 8+o | colspan=2|2+/4 | 4+/4 | colspan=2| | ||
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| 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| | ||
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|[4,3,4]+ | [4,31,1]+ | colspan=2| | colspan=2| | |||||||
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!rowspan=5|Hextetrahedral !215 | 216 | 217 | 218 | 219 | 220 | colspan=4| | ||||
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| P{{overline|4}}3m | F{{overline|4}}3m | I{{overline|4}}3m | P{{overline|4}}3n | F{{overline|4}}3c | I{{overline|4}}3d | colspan=4| | ||||
BGCOLOR="#e0e0ff" align=center | 2o:2 | 1o:2 | 4o:2 | 4o | 2oo | 4o/4 | colspan=4| | |||
BGCOLOR="#ffffd0" align=center | P33 | F33 | I33 | Pn3n3n | Fc3c3a | Id3d3d | colspan=4| | |||
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|[(4,3,4,2+)] | [3[4]] | [+(4,{3),4}+] | colspan=4| | |||||||
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!rowspan=5|Hexoctahedral !221 | 222 | 223 | 224 | 225 | 226 | 227 | 228 | 229 | 230 | |
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| Pm{{overline|3}}m | Pn{{overline|3}}n | Pm{{overline|3}}n | Pn{{overline|3}}m | Fm{{overline|3}}m | Fm{{overline|3}}c | Fd{{overline|3}}m | Fd{{overline|3}}c | Im{{overline|3}}m | Ia{{overline|3}}d | |
BGCOLOR="#e0e0ff" align=center | 4−:2 | 8oo | 8o | 4+:2 | 2−:2 | 4−− | 2+:2 | 4++ | 8o:2 | 8o/4 |
BGCOLOR="#ffffd0" align=center | P43 | Pn4n3n | P4n3n | Pn43 | F43 | F4c3a | Fd4n3 | Fd4c3a | I43 | Ib4d3d |
BGCOLOR="#e0ffe0" align=center | [4,3,4] | [(4+,2+)[3[4] | [4,31,1] | [4,(3,4)+] |
References
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- {{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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