Ref: http://arxiv.org/abs/0711.3220
Fourvector algebra
Author: Diego Saa (Submitted on 20 Nov 2007)
Abstract: The algebra of fourvectors is described. The fourvectors are more appropriate than the Hamilton quaternions for its use in Physics and the sciences in general. The fourvectors embrace the 3D vectors in a natural form. It is shown the excellent ability to perform rotations with the use of fourvectors, as well as their use in relativity for producing Lorentz boosts, which are understood as simple rotations.
axiom
_*_*(x,y)==concat(x(1) * y(1) + dot(x(2..), y(2..)), x(1) * y(2..) - x(2..) * y(1) + cross(x(2..), y(2..)))
Type: Void
axiom
e:Vector INT:=[1,0,0,0]
Type: Vector Integer
axiom
i:Vector INT:=[0,1,0,0]
Type: Vector Integer
axiom
j:Vector INT:=[0,0,1,0]
Type: Vector Integer
axiom
k:Vector INT:=[0,0,0,1]
Type: Vector Integer
axiom
test(e**e=e) and _
test(i**i=e) and _
test(j**j=e) and _
test(k**k=e) and _
test(e**i=i) and _
test(e**j=j) and _
test(e**k=k) and _
test(i**e=-i) and _
test(j**e=-j) and _
test(k**e=-k) and _
test(i**j=k) and _
test(j**i=-k) and _
test(k**i=j) and _
test(i**k=-j) and _
test(j**k=i) and _
test(k**j=-i)
axiom
Compiling function ** with type (Vector Integer,Vector Integer) ->
Vector Integer
Type: Boolean
Axiom has a domain for NonAssociative? Algebra
This is documented in the article:
Computations in Algebras of Fixed Rank by Johannes Grabmeir and Robert Wisbauer, from the book "Computational Algebra"
By Klaus G. Fischer, Philippe Loustaunau, Jay Shapiro.
The algebra above can be given by structural constants.
axiom
)clear all
All user variables and function definitions have been cleared.
sc:Vector Matrix Fraction Integer := [ _
[[ 1, 0, 0, 0], _
[ 0, 1, 0, 0], _
[ 0, 0, 1, 0], _
[ 0, 0, 0, 1]], _
[[ 0, 1, 0, 0], _
[-1, 0, 0, 0], _
[ 0, 0, 0, 1], _
[ 0, 0,-1, 0]], _
[[ 0, 0, 1, 0], _
[ 0, 0, 0,-1], _
[-1, 0, 0, 0], _
[ 0, 1, 0, 0]], _
[[ 0, 0, 0, 1], _
[ 0, 0, 1, 0], _
[ 0,-1, 0, 0], _
[-1, 0, 0, 0]]];
Type: Vector Matrix Fraction Integer
axiom
V:=AlgebraGivenByStructuralConstants(Fraction Integer, 4, [e,i,j,k],sc)
Type: Domain
axiom
)show V
AlgebraGivenByStructuralConstants(Fraction Integer,4,[e,i,j,k],[MATRIX,MATRIX,MATRIX,MATRIX]) is a domain constructor.
Abbreviation for AlgebraGivenByStructuralConstants is ALGSC
This constructor is exposed in this frame.
Issue )edit /usr/local/lib/axiom/target/x86_64-unknown-linux/../../src/algebra/ALGSC.spad to see algebra source code for ALGSC
------------------------------- Operations --------------------------------
?*? : (Fraction Integer,%) -> % ?*? : (Integer,%) -> %
?*? : (PositiveInteger,%) -> % ?*? : (%,Fraction Integer) -> %
?*? : (%,%) -> % ?**? : (%,PositiveInteger) -> %
?+? : (%,%) -> % ?-? : (%,%) -> %
-? : % -> % ?=? : (%,%) -> Boolean
0 : () -> % alternative? : () -> Boolean
antiAssociative? : () -> Boolean antiCommutative? : () -> Boolean
antiCommutator : (%,%) -> % associative? : () -> Boolean
associator : (%,%,%) -> % basis : () -> Vector %
coerce : % -> OutputForm commutative? : () -> Boolean
commutator : (%,%) -> % flexible? : () -> Boolean
hash : % -> SingleInteger jacobiIdentity? : () -> Boolean
jordanAdmissible? : () -> Boolean jordanAlgebra? : () -> Boolean
latex : % -> String leftAlternative? : () -> Boolean
leftNorm : % -> Fraction Integer leftTrace : % -> Fraction Integer
lieAdmissible? : () -> Boolean lieAlgebra? : () -> Boolean
powerAssociative? : () -> Boolean rank : () -> PositiveInteger
recip : % -> Union(%,"failed") rightAlternative? : () -> Boolean
rightNorm : % -> Fraction Integer sample : () -> %
someBasis : () -> Vector % unit : () -> Union(%,"failed")
zero? : % -> Boolean ?~=? : (%,%) -> Boolean
?*? : (NonNegativeInteger,%) -> %
?*? : (SquareMatrix(4,Fraction Integer),%) -> %
apply : (Matrix Fraction Integer,%) -> %
associatorDependence : () -> List Vector Fraction Integer
coerce : Vector Fraction Integer -> %
conditionsForIdempotents : Vector % -> List Polynomial Fraction Integer
conditionsForIdempotents : () -> List Polynomial Fraction Integer
convert : % -> Vector Fraction Integer
convert : Vector Fraction Integer -> %
coordinates : (Vector %,Vector %) -> Matrix Fraction Integer
coordinates : Vector % -> Matrix Fraction Integer
coordinates : (%,Vector %) -> Vector Fraction Integer
coordinates : % -> Vector Fraction Integer
?.? : (%,Integer) -> Fraction Integer
leftCharacteristicPolynomial : % -> SparseUnivariatePolynomial Fraction Integer
leftDiscriminant : Vector % -> Fraction Integer
leftDiscriminant : () -> Fraction Integer
leftMinimalPolynomial : % -> SparseUnivariatePolynomial Fraction Integer
leftPower : (%,PositiveInteger) -> %
leftRankPolynomial : () -> SparseUnivariatePolynomial Polynomial Fraction Integer
leftRecip : % -> Union(%,"failed")
leftRegularRepresentation : (%,Vector %) -> Matrix Fraction Integer
leftRegularRepresentation : % -> Matrix Fraction Integer
leftTraceMatrix : Vector % -> Matrix Fraction Integer
leftTraceMatrix : () -> Matrix Fraction Integer
leftUnit : () -> Union(%,"failed")
leftUnits : () -> Union(Record(particular: %,basis: List %),"failed")
noncommutativeJordanAlgebra? : () -> Boolean
plenaryPower : (%,PositiveInteger) -> %
represents : (Vector Fraction Integer,Vector %) -> %
represents : Vector Fraction Integer -> %
rightCharacteristicPolynomial : % -> SparseUnivariatePolynomial Fraction Integer
rightDiscriminant : Vector % -> Fraction Integer
rightDiscriminant : () -> Fraction Integer
rightMinimalPolynomial : % -> SparseUnivariatePolynomial Fraction Integer
rightPower : (%,PositiveInteger) -> %
rightRankPolynomial : () -> SparseUnivariatePolynomial Polynomial Fraction Integer
rightRecip : % -> Union(%,"failed")
rightRegularRepresentation : (%,Vector %) -> Matrix Fraction Integer
rightRegularRepresentation : % -> Matrix Fraction Integer
rightTrace : % -> Fraction Integer
rightTraceMatrix : Vector % -> Matrix Fraction Integer
rightTraceMatrix : () -> Matrix Fraction Integer
rightUnit : () -> Union(%,"failed")
rightUnits : () -> Union(Record(particular: %,basis: List %),"failed")
structuralConstants : Vector % -> Vector Matrix Fraction Integer
structuralConstants : () -> Vector Matrix Fraction Integer
subtractIfCan : (%,%) -> Union(%,"failed")
Type: Vector AlgebraGivenByStructuralConstants
?(Fraction Integer,4,[e,i,j,k]
?,[MATRIX,MATRIX,MATRIX,MATRIX]
?)
axiom
matrix([[(a.i * a.j) for j in 1..4] for i in 1..4])$OutputForm
Type: Union(AlgebraGivenByStructuralConstants
?(Fraction Integer,4,[e,i,j,k]
?,[MATRIX,MATRIX,MATRIX,MATRIX]
?),...)
axiom
rightUnit()$V
this algebra has no right unit
Type: Union("failed",...)
axiom
alternative?()$V
algebra is not left alternative
Type: Boolean
axiom
leftAlternative?()$V
algebra is not left alternative
Type: Boolean
axiom
rightAlternative?()$V
algebra is not right alternative
Type: Boolean
axiom
associative?()$V
algebra is not associative
Type: Boolean
axiom
antiAssociative?()$V
algebra is not anti-associative
Type: Boolean
axiom
--powerAssociative?()$V
commutative?()$V
algebra is not commutative
Type: Boolean
axiom
jordanAlgebra?()$V
algebra is not commutative
this is not a Jordan algebra
Type: Boolean
axiom
jordanAdmissible?()$V
algebra is not Jordan admissible
Type: Boolean
axiom
noncommutativeJordanAlgebra?()$V
algebra is not flexible
this is not a noncommutative Jordan algebra, as it is not flexible
Type: Boolean
axiom
lieAlgebra?()$V
algebra is not anti-commutative
this is not a Lie algebra
Type: Boolean
axiom
lieAdmissible?()$V
algebra is not Lie admissible
Type: Boolean
axiom
jacobiIdentity?()$V
Jacobi identity does not hold
Type: Boolean