The bases are the vectors e1, e2, e3, e4 and e5, however the higher level products such as: e1^e2, e3^e1, e2^e3, e1^e4, e4^e2 and e3^e4 is also as a basis for the bivectors.
The question is what order do we choose for this (which is equivalent to saying what sign do we use since e1^e2=-e2^e1).
The methodology used for choosing the order of these indexes is explained here.
We calculate the psuedoscalar by drawing the
matrix formed by putting the basis vectors side-by-side, then taking
its minor by removing the row associated with its own coordinate type
and removing the column of the basis vector not associated with.
We have to be very careful with signs as the sign
alternates with terms as follows:
| e1x |
e2x |
e3x |
e4x |
e5x |
| e1y |
e2y |
e3y |
e4y |
e5y |
| e1z |
e2z |
e3z |
e4z |
e5z |
| e1w |
e2w |
e3w |
e4w |
e5w |
| e1v |
e2v |
e3v |
e4v |
e5v |
|
=e1x* |
| e2y |
e3y |
e4y |
e5y |
| e2z |
e3z |
e4z |
e5z |
| e2w |
e3w |
e4w |
e5w |
| e2v |
e3v |
e4v |
e5v |
|
-e2x* |
| e1y |
e3y |
e4y |
e5y |
| e1z |
e3z |
e4z |
e5z |
| e1w |
e3w |
e4w |
e5w |
| e1v |
e3v |
e4v |
e5v |
|
+e3x* |
| e1y |
e2y |
e4y |
e5y |
| e1z |
e2z |
e4z |
e5z |
| e1w |
e2w |
e4w |
e5w |
| e1v |
e2v |
e4v |
e5v |
|
-e4x* |
| e1y |
e2y |
e3y |
e5y |
| e1z |
e2z |
e3z |
e5z |
| e1w |
e2w |
e3w |
e5w |
| e1v |
e2v |
e3v |
e5v |
|
+e5x* |
| e1y |
e2y |
e3y |
e4y |
| e1z |
e2z |
e3z |
e4z |
| e1w |
e2w |
e3w |
e4w |
| e1v |
e2v |
e3v |
e4v |
|
To choose tri-vectors for 5D multivectors we start with the psudoscalar e1^e2^e3^e4^e5 which represents the whole determinant. We then split it up, taking into account the sign, as above:
e1^e2^e3^e4^e5 = e1 * e2^e3^e4^e5 - e2 * e1^e3^e4^e5 + e3 * e1^e2^e4^e5 - e4 * e1^e2^e3^e5 + e5 * e1^e2^e3^e4
Where the sign is negative then we invert the order, which gives the basis tri-vectors as follows:
- e2^e3^e4^e5 is the minor of e1
- -e1^e3^e4^e5 is the minor of e2
- e1^e2^e4^e5 is the minor of e3
- -e1^e2^e3^e5 is the minor of e4
- e1^e2^e3^e4 is the minor of e5
In order to remove the minus terms from the 2nd and 4th terms we can just swap any two of the terms, but which two do we swap?
how about:
- e2^e3^e4^e5 is the minor of e1
- e3^e1^e4^e5 is the minor of e2
- e1^e2^e4^e5 is the minor of e3
- e1^e2^e5^e3 is the minor of e4
- e1^e2^e3^e4 is the minor of e5
I'm not an expert at suduko, so I cant get one number in each row, but the above seems to have a patern. Can anyone tell me a better way to choose the order?
What are the properties of these under the dual function?
So this is the best I can do to get the order for the quad-vectors.
What about the bivectors and tri-vectors? we can reduce the deteminant in two stages, but how does that correspond to the clifford algebra functions?
I think I will try finding the minors of the above tri-vectors as follows:
The minor of e1 |
The minor of e2 |
The minor of e3 |
The minor of e4 |
The minor of e5 |
| e2^e3^e4^e5 |
e1^e3^e4^e5 |
e1^e2^e4^e5 |
e1^e2^e3^e5 |
e1^e2^e3^e4 |
| |
Now take the minor of e1:
which gives: e3^e4^e5 |
Now take the minor of e1:
which gives: -e2^e4^e5 |
Now take the minor of e1:
which gives: e2^e3^e5 |
Now take the minor of e1:
which gives: -e2^e3^e4 |
Now take the minor of e2:
which gives: e3^e4^e5 |
|
Or take the minor of e2:
which gives: e1^e4^e5 |
Or take the minor of e2:
which gives: -e1^e3^e5 |
Or take the minor of e2:
which gives: e1^e3^e4 |
Or take the minor of e3:
which gives: -e2^e4^e5 |
Or take the minor of e3:
which gives: e1^e4^e5 |
|
Or take the minor of e3:
which gives: e1^e2^e5 |
Or take the minor of e3:
which gives: -e1^e2^e4 |
Or take the minor of e4:
which gives: e2^e3^e5 |
Or take the minor of e4:
which gives: -e1^e3^e5 |
Or take the minor of e4:
which gives: e1^e2^e5 |
|
Or take the minor of e4:
which gives: e1^e2^e3 |
Or take the minor of e5:
which gives: -e2^e3^e4 |
Or take the minor of e5:
which gives: e1^e3^e4 |
Or take the minor of e4:
which gives: -e1^e2^e4 |
Or take the minor of e5:
which gives: e1^e2^e3 |
|
so to summarise:
| minor of e1 followed by e2 gives: |
e1^e2 |
e3^e4^e5 |
(e1^e2)(e3^e4^e5) |
| minor of e1 followed by e3 gives: |
e1^e3 |
-e2^e4^e5 |
-(e1^e3)(e2^e4^e5) |
| minor of e1 followed by e4 gives: |
e1^e4 |
e2^e3^e5 |
(e1^e4)(e2^e3^e5) |
| minor of e1 followed by e5 gives: |
e1^e5 |
-e2^e3^e4 |
-(e1^e5)(e2^e3^e4) |
| minor of e2 followed by e1 gives: |
e2^e1 |
-e3^e4^e5 |
-(e2^e1)(e3^e4^e5) |
| minor of e2 followed by e3 gives: |
e2^e3 |
e1^e4^e5 |
(e2^e3)(e1^e4^e5) |
| minor of e2 followed by e4 gives: |
e2^e4 |
-e1^e3^e5 |
-(e2^e4)(e1^e3^e5) |
| minor of e2 followed by e5 gives: |
e2^e5 |
e1^e3^e4 |
(e2^e5)(e1^e3^e4) |
| minor of e3 followed by e1 gives: |
e3^e1 |
e2^e4^e5 |
(e3^e1)(e2^e4^e5) |
| minor of e3 followed by e2 gives: |
e3^e2 |
-e1^e4^e5 |
-(e3^e2)(e1^e4^e5) |
| minor of e3 followed by e4 gives: |
e3^e4 |
e1^e2^e5 |
(e3^e4)(e1^e2^e5) |
| minor of e3 followed by e5 gives: |
e3^e5 |
-e1^e2^e4 |
-(e3^e5)(e1^e2^e4) |
| minor of e4 followed by e1 gives: |
e4^e1 |
-e2^e3^e5 |
-(e4^e1)(e2^e3^e5) |
| minor of e4 followed by e2 gives: |
e4^e2 |
e1^e3^e5 |
(e4^e2)(e1^e3^e5) |
| minor of e4 followed by e3 gives: |
e4^e3 |
-e1^e2^e5 |
-(e4^e3)(e1^e2^e5) |
| minor of e4 followed by e5 gives: |
e4^e5 |
e1^e2^e3 |
(e4^e5)(e1^e2^e3) |
| minor of e5 followed by e1 gives: |
e5^e1 |
e2^e3^e4 |
(e5^e1)(e2^e3^e4) |
| minor of e5 followed by e2 gives: |
e5^e2 |
-e1^e3^e4 |
-(e5^e2)(e1^e3^e4) |
| minor of e5 followed by e3 gives: |
e5^e3 |
e1^e2^e4 |
(e5^e3)(e1^e2^e4) |
| minor of e5 followed by e4 gives: |
e5^e4 |
-e1^e2^e3 |
-(e5^e4)(e1^e2^e3) |
So the full multivector and its dual is:
Ar |
dual(Ar) = Ar* = e12345 Ar |
| 1 |
e12345 |
| e1 |
e12345e1= e2345 |
| e2 |
e12345e2 = e3145 |
| e3 |
e12345e3 = e1245 |
| e4 |
e12345e4 = e1253 |
| e5 |
e12345e5 = e1234 |
| e12 |
e12345e12= -e345 |
| e13 |
e12345e13= -e425 |
| e14 |
e12345e14= -e235 |
| e15 |
e12345e15= -e324 |
| e23 |
e12345e23= -e145 |
| e24 |
e12345e24= -e315 |
| e25 |
e12345e25= -e134 |
| e34 |
e12345e34= -e125 |
| e35 |
e12345e35= -e214 |
| e45 |
e12345e45=-e123 |
| e123 |
e12345e123= -e45 |
| e214 |
e12345e214= -e35 |
| e125 |
e12345e125= -e34 |
| e134 |
e12345e134= -e25 |
| e315 |
e12345e315= -e24 |
| e145 |
e12345e145= -e23 |
| e324 |
e12345e324= -e15 |
| e235 |
e12345e235= -e14 |
| e425 |
e12345e425= -e13 |
| e345 |
e12345e345=-e12 |
| e1234 |
e12345e1234= e5 |
| e1253 |
e12345e1253= e4 |
| e1245 |
e12345e1245= e3 |
| e3145 |
e12345e3145= e2 |
| e2345 |
e12345e2345= e1 |
| e12345 |
e12345e12345= 1 |
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metadata block |
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| see also: |
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| Correspondence about this page |
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Book Shop - Further reading.
Where I can, I have put links to Amazon for books that are relevant to
the subject, click on the appropriate country flag to get more details
of the book or to buy it from them. |
Clifford Algebra to Geometric Calculus: A Unified Language for Mathematics and
Physics (Fundamental Theories of Physics). This book is intended for mathematicians
and physicists rather than programmers, it is very theoretical. It covers the
algebra and calculus of multivectors of any dimension and is not specific to 3D modelling.
|
|
Commercial Software Shop
Where I can, I have put links to Amazon for commercial software, not
directly related to the software project, but related to the subject being
discussed, click on the appropriate country flag to get more details of
the software or to buy it from them. |
Mathmatica
|
Can you help?
Please send me any improvements to here. I would appreciate ideas to make the pages more useful including
error correction, ideas for new pages, improvements to wording. It helps
if you quote the full URL of the page. |
|
|
Terminology and Notation
Specific to this page here:
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|
program
I am working on a project which uses these principles, if you would like
to help me with this you are welcome to join in, here: |
http://sourceforge.net/projects/mjbworld/ |
This site may have errors. Don't use for critical systems.
Copyright (c) 1998-2008 Martin John Baker - All rights reserved.