The speakers are asked to choose a work of art that particularly interests them and they discuss it from the point of view of their discipline.
Scientists bring an enormous amount of research as well as appreciation to the task.
The ball bearings are of a standard kind as are the various nuts and bolts and right angle pieces that attach the glass plates to the axle. It seems clear that Duchamp did not think of the apparatus itself as art. It is often said that Duchamp thought that art was conceived primarily as a 'mental act,' and in this context it appears to me that the mental act of perceiving the black and white circular segments as full circles was the art that Duchamp intended. A chair is for sitting. A doorknob for turning.