في الجبر التجريدي، السـِدِنيون Sedenion يشكل 16 بعداً جبرياً فوق الأعداد الحقيقية. يرمز لمجموعة السدنيون بالرمز S{\displaystyle \mathbb {S . يعهد حالياً نوعان من السيدينيون:
سيدينيون تم الحصول عليه من إنشاء كايلي-ديكسون
سيدينيون مخروطي (ذو16 بعداً جبرياً).
الحساب
A visualization of a 4D extension to the cubic octonion, showing the 35 triads as hyperplanes through the real (e0){\displaystyle (e_{0 ) vertex of the sedenion example given. Note that the only exception is that the triple (e1){\displaystyle (e_{1 ) , (e2){\displaystyle (e_{2 ) , (e3){\displaystyle (e_{3 ) doesn't form a hyperplane with (e0){\displaystyle (e_{0 ) .
بشكل مشابه للأوكتونيون، فإن عملية ضرب السدنيون هي عملية غير تبديلية وغير تجميعية. ولكنه يمتلك خاصية تجميع القوى.
كل سدنيون هوتعبير عن هجريب خطي لعناصره وهي: 1, e1, e2, e3, e4, e5, e6, e7, e8, e9, e10, e11, e12, e13, e14 and e15 والتي هي أسس الفضاء الشعاعي للسدنيون.
يعطى جدول ضرب عناصر السدنيون الستة عشرة على الشكل التالي:
Like octonions, multiplication of sedenions is neither commutative nor associative.
But in contrast to the octonions, the sedenions do not even have the property of being alternative.
They do, however, have the property of power associativity, which can be stated as that, for any element x of Sflexible.
Every sedenion is a linear combination of the unit sedenions e0{\displaystyle e_{0 , e1{\displaystyle e_{1 , e2{\displaystyle e_{2 , e3{\displaystyle e_{3 , ...,e15{\displaystyle e_{15 ,
which form a basis of the vector space of sedenions. Every sedenion can be represented in the form
Addition and subtraction are defined by the addition and subtraction of corresponding coefficients and multiplication is distributive over addition.
Like other algebras based on the Cayley–Dickson construction, the sedenions contain the algebra they were constructed from. So, they contain the octonions (generated by e0{\displaystyle e_{0 to e7{\displaystyle e_{7 in the table below), and therefore also the quaternions (generated by e0{\displaystyle e_{0 to e3{\displaystyle e_{3 ), complex numbers (generated by e0{\displaystyle e_{0 and e1{\displaystyle e_{1 ) and reals (generated by e0{\displaystyle e_{0 ).
The sedenions have a multiplicative identity element e0division algebra because they have zero divisors. This means that two non-zero sedenions can be multiplied to obtain zero: an example is (e3hypercomplex number systems after sedenions that are based on the Cayley–Dickson construction contain zero divisors.
جدول ضرب السدنيونات هوالتالي:
جدول الضرب
multiplier ej{\displaystyle e_{j
eiej{\displaystyle e_{i e_{j
e0{\displaystyle e_{0
e1{\displaystyle e_{1
e2{\displaystyle e_{2
e3{\displaystyle e_{3
e4{\displaystyle e_{4
e5{\displaystyle e_{5
e6{\displaystyle e_{6
e7{\displaystyle e_{7
e8{\displaystyle e_{8
e9{\displaystyle e_{9
e10{\displaystyle e_{10
e11{\displaystyle e_{11
e12{\displaystyle e_{12
e13{\displaystyle e_{13
e14{\displaystyle e_{14
e15{\displaystyle e_{15
multiplicand ei{\displaystyle e_{i
e0{\displaystyle e_{0
e0{\displaystyle e_{0
e1{\displaystyle e_{1
e2{\displaystyle e_{2
e3{\displaystyle e_{3
e4{\displaystyle e_{4
e5{\displaystyle e_{5
e6{\displaystyle e_{6
e7{\displaystyle e_{7
e8{\displaystyle e_{8
e9{\displaystyle e_{9
e10{\displaystyle e_{10
e11{\displaystyle e_{11
e12{\displaystyle e_{12
e13{\displaystyle e_{13
e14{\displaystyle e_{14
e15{\displaystyle e_{15
e1{\displaystyle e_{1
e1{\displaystyle e_{1
−e0{\displaystyle e_{0
e3{\displaystyle e_{3
−e2{\displaystyle e_{2
e5{\displaystyle e_{5
−e4{\displaystyle e_{4
−e7{\displaystyle e_{7
e6{\displaystyle e_{6
e9{\displaystyle e_{9
−e8{\displaystyle e_{8
−e11{\displaystyle e_{11
e10{\displaystyle e_{10
−e13{\displaystyle e_{13
e12{\displaystyle e_{12
e15{\displaystyle e_{15
−e14{\displaystyle e_{14
e2{\displaystyle e_{2
e2{\displaystyle e_{2
−e3{\displaystyle e_{3
−e0{\displaystyle e_{0
e1{\displaystyle e_{1
e6{\displaystyle e_{6
e7{\displaystyle e_{7
−e4{\displaystyle e_{4
−e5{\displaystyle e_{5
e10{\displaystyle e_{10
e11{\displaystyle e_{11
−e8{\displaystyle e_{8
−e9{\displaystyle e_{9
−e14{\displaystyle e_{14
−e15{\displaystyle e_{15
e12{\displaystyle e_{12
e13{\displaystyle e_{13
e3{\displaystyle e_{3
e3{\displaystyle e_{3
e2{\displaystyle e_{2
−e1{\displaystyle e_{1
−e0{\displaystyle e_{0
e7{\displaystyle e_{7
−e6{\displaystyle e_{6
e5{\displaystyle e_{5
−e4{\displaystyle e_{4
e11{\displaystyle e_{11
−e10{\displaystyle e_{10
e9{\displaystyle e_{9
−e8{\displaystyle e_{8
−e15{\displaystyle e_{15
e14{\displaystyle e_{14
−e13{\displaystyle e_{13
e12{\displaystyle e_{12
e4{\displaystyle e_{4
e4{\displaystyle e_{4
−e5{\displaystyle e_{5
−e6{\displaystyle e_{6
−e7{\displaystyle e_{7
−e0{\displaystyle e_{0
e1{\displaystyle e_{1
e2{\displaystyle e_{2
e3{\displaystyle e_{3
e12{\displaystyle e_{12
e13{\displaystyle e_{13
e14{\displaystyle e_{14
e15{\displaystyle e_{15
−e8{\displaystyle e_{8
−e9{\displaystyle e_{9
−e10{\displaystyle e_{10
−e11{\displaystyle e_{11
e5{\displaystyle e_{5
e5{\displaystyle e_{5
e4{\displaystyle e_{4
−e7{\displaystyle e_{7
e6{\displaystyle e_{6
−e1{\displaystyle e_{1
−e0{\displaystyle e_{0
−e3{\displaystyle e_{3
e2{\displaystyle e_{2
e13{\displaystyle e_{13
−e12{\displaystyle e_{12
e15{\displaystyle e_{15
−e14{\displaystyle e_{14
e9{\displaystyle e_{9
−e8{\displaystyle e_{8
e11{\displaystyle e_{11
−e10{\displaystyle e_{10
e6{\displaystyle e_{6
e6{\displaystyle e_{6
e7{\displaystyle e_{7
e4{\displaystyle e_{4
−e5{\displaystyle e_{5
−e2{\displaystyle e_{2
e3{\displaystyle e_{3
−e0{\displaystyle e_{0
−e1{\displaystyle e_{1
e14{\displaystyle e_{14
−e15{\displaystyle e_{15
−e12{\displaystyle e_{12
e13{\displaystyle e_{13
e10{\displaystyle e_{10
−e11{\displaystyle e_{11
−e8{\displaystyle e_{8
e9{\displaystyle e_{9
e7{\displaystyle e_{7
e7{\displaystyle e_{7
−e6{\displaystyle e_{6
e5{\displaystyle e_{5
e4{\displaystyle e_{4
−e3{\displaystyle e_{3
−e2{\displaystyle e_{2
e1{\displaystyle e_{1
−e0{\displaystyle e_{0
e15{\displaystyle e_{15
e14{\displaystyle e_{14
−e13{\displaystyle e_{13
−e12{\displaystyle e_{12
e11{\displaystyle e_{11
e10{\displaystyle e_{10
−e9{\displaystyle e_{9
−e8{\displaystyle e_{8
e8{\displaystyle e_{8
e8{\displaystyle e_{8
−e9{\displaystyle e_{9
−e10{\displaystyle e_{10
−e11{\displaystyle e_{11
−e12{\displaystyle e_{12
−e13{\displaystyle e_{13
−e14{\displaystyle e_{14
−e15{\displaystyle e_{15
−e0{\displaystyle e_{0
e1{\displaystyle e_{1
e2{\displaystyle e_{2
e3{\displaystyle e_{3
e4{\displaystyle e_{4
e5{\displaystyle e_{5
e6{\displaystyle e_{6
e7{\displaystyle e_{7
e9{\displaystyle e_{9
e9{\displaystyle e_{9
e8{\displaystyle e_{8
−e11{\displaystyle e_{11
e10{\displaystyle e_{10
−e13{\displaystyle e_{13
e12{\displaystyle e_{12
e15{\displaystyle e_{15
−e14{\displaystyle e_{14
−e1{\displaystyle e_{1
−e0{\displaystyle e_{0
−e3{\displaystyle e_{3
e2{\displaystyle e_{2
−e5{\displaystyle e_{5
e4{\displaystyle e_{4
e7{\displaystyle e_{7
−e6{\displaystyle e_{6
e10{\displaystyle e_{10
e10{\displaystyle e_{10
e11{\displaystyle e_{11
e8{\displaystyle e_{8
−e9{\displaystyle e_{9
−e14{\displaystyle e_{14
−e15{\displaystyle e_{15
e12{\displaystyle e_{12
e13{\displaystyle e_{13
−e2{\displaystyle e_{2
e3{\displaystyle e_{3
−e0{\displaystyle e_{0
−e1{\displaystyle e_{1
−e6{\displaystyle e_{6
−e7{\displaystyle e_{7
e4{\displaystyle e_{4
e5{\displaystyle e_{5
e11{\displaystyle e_{11
e11{\displaystyle e_{11
−e10{\displaystyle e_{10
e9{\displaystyle e_{9
e8{\displaystyle e_{8
−e15{\displaystyle e_{15
e14{\displaystyle e_{14
−e13{\displaystyle e_{13
e12{\displaystyle e_{12
−e3{\displaystyle e_{3
−e2{\displaystyle e_{2
e1{\displaystyle e_{1
−e0{\displaystyle e_{0
−e7{\displaystyle e_{7
e6{\displaystyle e_{6
−e5{\displaystyle e_{5
e4{\displaystyle e_{4
e12{\displaystyle e_{12
e12{\displaystyle e_{12
e13{\displaystyle e_{13
e14{\displaystyle e_{14
e15{\displaystyle e_{15
e8{\displaystyle e_{8
−e9{\displaystyle e_{9
−e10{\displaystyle e_{10
−e11{\displaystyle e_{11
−e4{\displaystyle e_{4
e5{\displaystyle e_{5
e6{\displaystyle e_{6
e7{\displaystyle e_{7
−e0{\displaystyle e_{0
−e1{\displaystyle e_{1
−e2{\displaystyle e_{2
−e3{\displaystyle e_{3
e13{\displaystyle e_{13
e13{\displaystyle e_{13
−e12{\displaystyle e_{12
e15{\displaystyle e_{15
−e14{\displaystyle e_{14
e9{\displaystyle e_{9
e8{\displaystyle e_{8
e11{\displaystyle e_{11
−e10{\displaystyle e_{10
−e5{\displaystyle e_{5
−e4{\displaystyle e_{4
e7{\displaystyle e_{7
−e6{\displaystyle e_{6
e1{\displaystyle e_{1
−e0{\displaystyle e_{0
e3{\displaystyle e_{3
−e2{\displaystyle e_{2
e14{\displaystyle e_{14
e14{\displaystyle e_{14
−e15{\displaystyle e_{15
−e12{\displaystyle e_{12
e13{\displaystyle e_{13
e10{\displaystyle e_{10
−e11{\displaystyle e_{11
e8{\displaystyle e_{8
e9{\displaystyle e_{9
−e6{\displaystyle e_{6
−e7{\displaystyle e_{7
−e4{\displaystyle e_{4
e5{\displaystyle e_{5
e2{\displaystyle e_{2
−e3{\displaystyle e_{3
−e0{\displaystyle e_{0
e1{\displaystyle e_{1
e15{\displaystyle e_{15
e15{\displaystyle e_{15
e14{\displaystyle e_{14
−e13{\displaystyle e_{13
−e12{\displaystyle e_{12
e11{\displaystyle e_{11
e10{\displaystyle e_{10
−e9{\displaystyle e_{9
e8{\displaystyle e_{8
−e7{\displaystyle e_{7
e6{\displaystyle e_{6
−e5{\displaystyle e_{5
−e4{\displaystyle e_{4
e3{\displaystyle e_{3
e2{\displaystyle e_{2
−e1{\displaystyle e_{1
−e0{\displaystyle e_{0
Sedenion properties
From the above table, we can see that:
e0ei=eie0=eifor alli,{\displaystyle e_{0 e_{i =e_{i e_{0 =e_{i \,{\text{for all \,i,
The sedenions are not fully anti-associative. Choose any four generators, i,j,k{\displaystyle i,j,k and l{\displaystyle l . The following 5-cycle shows that at least one of these relations must associate.
In particular, in the table above, using e1,e2,e4{\displaystyle e_{1 ,e_{2 ,e_{4 and e8{\displaystyle e_{8 the last expression associates.
(e1e2)e12=e1(e2e12)=−e15{\displaystyle (e_{1 e_{2 )e_{12 =e_{1 (e_{2 e_{12 )=-e_{15
Quaternionic subalgebras
The 35 triads that make up this specific sedenion multiplication table with theسبعة triads of the octonions used in creating the sedenion through the Cayley–Dickson construction shown in bold:
The binary representations of the indices of these triples xor to 0.
The list of 84 sets of zero divisors {ea{\displaystyle e_{a , eb{\displaystyle e_{b , ec{\displaystyle e_{c , ed{\displaystyle e_{d , where
(ea{\displaystyle e_{a + eb{\displaystyle e_{b )∘{\displaystyle \circ (ec{\displaystyle e_{c + ed{\displaystyle e_{d )=0:
التطبيقات
Moreno (1998) showed that the space of pairs of norm-one sedenions that multiply to zero is homeomorphic to the compact form of the exceptional Lie group . (Note that in his paper, a "zero divisor" means a pair of elements that multiply to zero.)
انظر أيضاً
Pfister's sixteen-square identity
Hypercomplex number
Split-complex number
الهامش
^(Baez 2002, p. 6)
المراجع
Imaeda, K.; Imaeda, M. (2000), "Sedenions: algebra and analysis", Applied Mathematics and Computation115 (2): 77–88, doi:10.1016/S0096-3003(99)00140-X
Baez, John C. (2002). "The Octonions". Bulletin of the American Mathematical Society. New Series. 39 (2): 145–205. arXiv:math/0105155. Bibcode:1994BAMaS..30..205W. doi:10.1090/S0273-0979-01-00934-X. MR 1886087.
Kinyon, M.K.; Phillips, J.D.; Vojtěchovský, P. (2007). "C-loops: Extensions and constructions". Journal of Algebra and Its Applications. 6 (1): 1–20. arXiv:math/0412390. CiteSeerX 10.1.1.240.6208. doi:10.1142/S0219498807001990.
Kivunge, Benard M.; Smith, Jonathan D. H (2004). "Subloops of sedenions" (PDF). Comment. Math. Univ. Carolinae. 45 (2): 295–302.
Moreno, Guillermo (1998), "The zero divisors of the Cayley–Dickson algebras over the real numbers", Bol. Soc. Mat. Mexicana, Series ثلاثة 4 (1): 13–28, Bibcode: 1997q.alg....10013G
Smith, Jonathan D. H. (1995), "A left loop on the 15-sphere", Journal of Algebra176 (1): 128–138, doi:10.1006/jabr.1995.1237