Key to his initial thinking and activities as an aesthetician, cultural theorist, curator, teacher and art critic was his encounter in the early 1950s with the kinetic artist (and author of the book Constructivism) George Rickey.

Op beckons forth a consideration of the enlargement of the audience's participatory role; both in regard to the perception of meaning and actual physical changes to the work of art.

These artists confirmed his interest in spectator participation, which brought him to the late 1980s and the 1990s when immersive virtual reality and digital art began to become established.

Popper began to investigate a range of works emerging in this era, including those of Shawn Brixey, Ebon Fisher, and Joseph Nechvatal.

As regards to virtual art, openness is stressed both from the point of view of the artists and their creativity and from that of the follow-up users in their reciprocating thoughts and actions.

Virtual art, as Popper saw it, is more than just an injection of the usual aesthetic material into a new medium, but a deep investigation into the ontological, psychological and ecological significance of such technologies.

Sharing Popper's focus on art and technology are Jack Burnham (Beyond Modern Sculpture 1968) and Gene Youngblood (Expanded Cinema 1970).