Hurwitz theorem (composition algebras)
E931272
Hurwitz theorem (composition algebras) is a fundamental result in algebra that classifies all finite-dimensional normed division algebras over the real numbers, showing that they exist only in dimensions 1, 2, 4, and 8.
All labels observed (1)
| Label | Occurrences |
|---|---|
| Hurwitz theorem (composition algebras) canonical | 2 |
How this entity was disambiguated
This entity first appeared as the object of triple T11534414 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
Target entity: Hurwitz theorem (composition algebras) Context triple: [Adolf Hurwitz, knownFor, Hurwitz theorem (composition algebras)]
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A.
Hurwitz theorem
Hurwitz theorem is a fundamental result in Diophantine approximation that gives an optimal bound on how well any irrational real number can be approximated by infinitely many rational numbers.
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B.
Hurwitz quaternions
Hurwitz quaternions are a specific lattice of quaternions with integer and half-integer components that form a maximal order in the quaternion algebra and provide a natural algebraic framework for understanding representations of integers as sums of four squares.
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C.
Hurwitz determinants
Hurwitz determinants are specific determinants constructed from a polynomial’s coefficients that are used to test whether all roots of the polynomial lie in the left half of the complex plane, thereby assessing system stability.
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D.
Hurwitz
Hurwitz is a surname of German and Ashkenazi Jewish origin borne by various notable individuals across fields such as mathematics, music, and law.
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E.
Hilbert symbol
The Hilbert symbol is a local arithmetic invariant in number theory that encodes whether a quadratic form represents zero over a given local field, playing a central role in local class field theory and reciprocity laws.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
Target entity: Hurwitz theorem (composition algebras) Target entity description: Hurwitz theorem (composition algebras) is a fundamental result in algebra that classifies all finite-dimensional normed division algebras over the real numbers, showing that they exist only in dimensions 1, 2, 4, and 8.
-
A.
Hurwitz theorem
Hurwitz theorem is a fundamental result in Diophantine approximation that gives an optimal bound on how well any irrational real number can be approximated by infinitely many rational numbers.
-
B.
Hurwitz quaternions
Hurwitz quaternions are a specific lattice of quaternions with integer and half-integer components that form a maximal order in the quaternion algebra and provide a natural algebraic framework for understanding representations of integers as sums of four squares.
-
C.
Hurwitz determinants
Hurwitz determinants are specific determinants constructed from a polynomial’s coefficients that are used to test whether all roots of the polynomial lie in the left half of the complex plane, thereby assessing system stability.
-
D.
Hurwitz
Hurwitz is a surname of German and Ashkenazi Jewish origin borne by various notable individuals across fields such as mathematics, music, and law.
-
E.
Hilbert symbol
The Hilbert symbol is a local arithmetic invariant in number theory that encodes whether a quadratic form represents zero over a given local field, playing a central role in local class field theory and reciprocity laws.
- F. None of above. chosen
Statements (47)
| Predicate | Object |
|---|---|
| instanceOf |
mathematical theorem
ⓘ
result in normed division algebras ⓘ theorem in algebra ⓘ |
| allowsDimensions |
1
ⓘ
2 ⓘ 4 ⓘ 8 ⓘ |
| characterizes |
C as the unique 2-dimensional real normed division algebra up to isomorphism
ⓘ
H as the unique 4-dimensional real normed division algebra up to isomorphism ⓘ O as the unique 8-dimensional real normed division algebra up to isomorphism ⓘ R as the unique 1-dimensional real normed division algebra ⓘ |
| classifies |
finite-dimensional real normed division algebras
ⓘ
real composition algebras with multiplicative norm ⓘ |
| concerns |
composition algebra
ⓘ
multiplicative norm ⓘ normed division algebra ⓘ quadratic form ⓘ real numbers ⓘ |
| describes |
possible dimensions of composition algebras over the reals
ⓘ
structure of real normed division algebras ⓘ |
| equivalentTo | classification of real composition algebras with nondegenerate multiplicative quadratic form ⓘ |
| field |
algebra
ⓘ
number theory ⓘ topology ⓘ |
| forbidsDimensions | any other positive integer dimension than 1, 2, 4, or 8 for real normed division algebras ⓘ |
| hasConsequence |
existence of normed bilinear maps R^n × R^n → R^n only for n = 1, 2, 4, 8
ⓘ
restriction on possible dimensions of parallelizable spheres ⓘ |
| hasVariant | Hurwitz theorem on composition of quadratic forms NERFINISHED ⓘ |
| historicalPeriod | late 19th century ⓘ |
| implies |
every finite-dimensional real normed division algebra is isomorphic to R, C, H, or O as a normed algebra
ⓘ
there are no real normed division algebras of dimension 3 ⓘ there are no real normed division algebras of dimension 5 ⓘ there are no real normed division algebras of dimension 6 ⓘ there are no real normed division algebras of dimension 7 ⓘ there are no real normed division algebras of dimension greater than 8 ⓘ |
| impliesExistenceOf | only four isomorphism classes of real normed division algebras ⓘ |
| namedAfter | Adolf Hurwitz NERFINISHED ⓘ |
| provedBy | Adolf Hurwitz NERFINISHED ⓘ |
| relatedTo |
complex numbers C
ⓘ
octonions O ⓘ quaternions H ⓘ real numbers R ⓘ |
| statement |
every finite-dimensional real normed division algebra has dimension 1, 2, 4, or 8
ⓘ
the only finite-dimensional real composition algebras with a positive-definite multiplicative norm have dimensions 1, 2, 4, or 8 ⓘ |
| usesConcept |
bilinear form
ⓘ
composition of quadratic forms ⓘ quadratic form identity ⓘ |
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Subject: Hurwitz theorem (composition algebras) Description of subject: Hurwitz theorem (composition algebras) is a fundamental result in algebra that classifies all finite-dimensional normed division algebras over the real numbers, showing that they exist only in dimensions 1, 2, 4, and 8.
Referenced by (2)
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