Steve Harrison proposed a concept a long time ago, which seems to be related to the idea of “spacetime” mentioned in the paper “Virtual Spacetime: Model, Technology, and Applications of Spacetime without Physical Constraints.”
In the context of media space, the term “media space” was used to refer to the concept of “spacetime.”
In a panel log available at https://www.billbuxton.com/mediaspacesCHI08.pdf, it is mentioned that Ron Baecker defined media space as “a computer-controlled teleconferencing or videoconferencing system in which audio and video communications are used to overcome the barriers of physical separation.”
For further reading on this topic, you can refer to “Media Space: 20+ Years of Mediated Life” and “Realizing Physical Remote Communication Spaces 4 - Understanding the Mechanism of Multi-Person Dialogue through Media.”