User:Maschen/Fractals in Clifford and geometric algebra
In applied computer graphics, fractals in geometric algebra and Clifford algebra are fractals generated using the tools of geometric algebra, an example of the more general formalisms of Clifford algebra.
Motivation
[edit]Surfaces and boundaries of real physical objects can be approximated accurately by fractals. Fractals are characterized by a self-similarly repeating geometric shape, which can be described using recurrence relations of numbers, for example the Cantor set is generated by real numbers, the infamous Mandelbrot set is generated by complex numbers, the 3d analogue called the Mandelbulb is generated by 3d Euclidean vectors, and other 4d fractals can be iterated by quaternions.
In geometric algebra, scalars, vectors, complex numbers and quaternions are all part of the same number system. The most general geometric object is a multivector, a sum of scalars and pseudoscalars, vectors and pseudovectors, and so on, and other numbers can be construed as certain cases of multivectors. Fractals can be generated by iterating multivectors which comprise scalars and pseudoscalars. Since multivectors add together objects of different dimensions (technically in GA, the term grade is used), multidimensional fractals can be generated by multivectors. An interesting feature of GA is that, like complex numbers and quaternions but unlike Euclidean vectors, functions (such as powers, sine, cosine, exponential, logarithm, etc) of multivectors can be defined, which easily allows non-linear maps to be defined.
Generation of fractals
[edit]Since fractals can be generated by a simple rule, the rule could remain constant throughout the generation of the fractal, i.e. the rule is deterministic. More interesting results occur when if the rule is changed randomly each time it's applied.
Applications
[edit]Computer graphics continues to experiment with applying GA. Fractals have been used to approximate realistic geometric shapes, as well as fractal interpolation to approximate plots and graphs where statistical methods alone are insufficient.
Multivector maps take the form:
See also
[edit]References
[edit]External links
[edit]- J. B. Kriska Construction of Fractal Objects with Iterated Function Systems
- M. Ibrahim, Robert J. Krawczyk, Exploring the Effect of Direction on Vector - Based Fractals
- [1]
- P. Bourke (2001) Quaternion Julia Fractals
- L. Dorst, D. Fontijne, S. Mann, Geometric algebra for computer science - an object orientated approach to geometry
- R. J. Wareham, J. Lasenby (2011) Generating Fractals Using Geometric Algebra, Volume 21, Issue 3, pp 647-659, Advances in Applied Clifford Algebras
- A. Jadczyk (2007) Quantum fractals on n-spheres. Clifford Algebra approach
- M. M. Oliveira, L. A. F. Fernandes, Introduction to Geometric Algebra, Summer School in Computer Graphics, 2010
- L. Dorst, D. Fontijne, S. Mann, Geometric Algebra for Computer Science: An Object-Oriented Approach to Geometry, publisher=Morgan Kaufmann, series=The Morgan Kaufmann Series in Computer Graphics, 2010, isbn=0080553109