Topological Slide: Artist's Statement  
Michael Scroggins: The
original grant application to the Art and Virtual Environments Project
proposed the use of a tiltable platform as a kinesthetic interface for
navigating upon topological surfaces. It went on to describe the project
in the following words:
This simple concept was the heart of the proposal and there was no conscious attempt to deal directly with the many interesting and complex conceptual issues surrounding VR. The Topological Slide was conceived to be a direct sensual experience of surface with overt handles for the intellect located in the mathematical concepts integral to the surfaces formation. In the early stages of the project, I tried to discourage any associations with surfing preferring instead to invoke the more general model of sliding. My attempts to avoid the surfing tag were doomed however, in light of the prevalent use of surfing as a metaphor. No one seemed to be speaking of "channel skating" or "internet skiing"! Ironically, the germinal idea for the Topological Slide did arise in an idle daydream of a VR surfing simulator. A constant tubular wave generator could allow the visual illusion of riding inside the most intense part of a wave. Getting tubed can be a transcendent experience as the level of concentration required to remain inside the tube can propel one into a state of mind where there is no past and no future, just a lucid present. Unfortunately, the surfing simulator idea unavoidably degenerated into the annoying notion of a kind of VR karaoke where one could replace Frankie and Annette as surf heroes. An
attempt to recuperate some aspect of the surfing model led me to consider
utilizing the continuous looping flow of a Mobius strip as a substitute
for a simulated wave. Reflecting on the topological properties of the Mobius
strip led to consideration of the Klien bottle and then on to the wide
range of minimal surfaces which Stewart Dickson had brought to my attention
years earlier.
A contributing factor to my personal fascination with the Topological Slide is my mathematical naivete. In addition to the sensual delight of navigating the surfaces in a very physical way, there is the drive to gain an understanding of the principles by which those surfaces are formed and the underlying concepts that make them interesting to mathematicians. In the course of dealing with these objects, my curiosity has been aroused enough to desire further education in mathematics. I have been forced to come to terms with how little I understand of nonEuclidian geometries and thus how limited my concepts of space have been. It is my hope that this project will also stimulate others particularly children to expand their mathematical understanding. I asked
my old friend and colleague, Stewart Dickson, to collaborate with me on
the project because of his deep interest in visual mathematics and experience
designing topological object databases. I was responsible for the design
and fabrication of the tilting platform, and as the person who conceived
and initiated the project, my primary role was to coordinate its overall
realization. Stewart provided the code for the topological objects and
was responsible for writing and implementing the original platform interface
routines. Subsequent programming necessary to realize the project was performed
by Graham Lindgren, John Harrison, and Glen Frazer. Further work in optimizing
the Topological Slide code and implementing edge control algorithms
was performed by Sean Halliday.
The construction of minimal surfaces by contemporary mathematicians like David Hoffman and William Meeks is an exercise of obtaining a specific topology with the geometry constrained to be the purest possible expression of the form. The breakthrough work they did used the computer to make pictures of the forms they were studying. The pictures showed them aspects of the objects they could not deduce from the equations alone. They began doing a kind of experimental mathematics which revolutionized their field of work. They began designing mathematical systems which were driven by a visuallyderived structural model. They then had a higher level pointofview from which they could advance their formal rigor. Documentation of this work can be found at www.gang.umass.edu. The
objects we have chosen to use in the Topological Slide are artifacts
of the historical legacy of cyberspace. The general problem of placing
the rider on a mathematically specified surface is fairly complex. First
the (X,Y,Z) coordinate in threespace on the mathematical surface must
be calculated as a function of the (U,V) coordinate in parametric space
of the rider's location. This location is the cumulative effect of the
two acceleration vectors specified by the platform tilt axes and a constant
friction or drag coefficient. The rider must then be oriented in a natural
manner to the surface at the correct threedimensional address.
In short, these calculations are nontrivial. I rely on Mathematica to obtain graphical representations of the surfaces. Even if I could derive Clanguage implementations of the calculations, it would not be advantageous to calculate them on the fly; therefore, we used precomputed CGIstyle geometry description records to represent the surfaces. I had originally intended that the Topological Slide contain an object which is in metamorphosis from its simplest form (disk, sphere, torus, etc.) into "full bloom". This action was intended to better illustrate the nature of the shape as well as to add dynamism to the riding experience. Another
class of surfaces we intended to illustrate was the threedimensional representation
of an entity which is defined in a higherdimensional space. I have prepared
pairs of immersions in threespace of the Real Projective Plane
which metamorphose one into another: The Veronese surface which metamorphoses
into the Steiner Roman surface and the Apery cylindrical parameterization
of the Roman surface which metamorphoses into the Werner Boy surface. I
also have two different (orthogonal) parameterizations of the Klein bottle
which transform one into the other. Further development time would have
allowed me to realize these goals.
1.
An excellent collection of essays on the subject can be found in Michelle
Emmer's The Visual Mind: Art and Mathematics (Cambridge, Massachusetts:
MIT Press, 1993)
2.
Carl Jung, The Collected Works of C. G. Jung, Vol. 8, "The Structure
and Dynamics of the Psyche", (Princeton University Press, Princeton, New
Jersey, 1969), 457.
3.
The ironic inversion inherent in this reading can be discerned in
Calvin Tomlin's The Bride and the Bachelors (London: Weidenfeld
and Nicholson, 1965), 26
4.
Paraphrased from Stephen Wolfram, Mathematica: A System for Doing Mathematics
by Computer. 2d ed. (Reading, Massachusets: AddisonWesley, 1990).






Introduction
Enneper's
Surface  JorgeMeeks Trinoid
 Artist's Statement
 Project Credits  Related
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