Academics fly around the world to meet coauthors, go to conferences or present seminars. These things could easily be done by videoconferencing, saving money, travel time, environment and productivity lost to jetlag. An objection I have heard is that video calls are not the same thing. What other senses besides sight and hearing do people use to communicate with their colleagues? A handshake maybe. Then build a robotic arm that gives haptic feedback to imitate any person’s hand and that can be used to shake hands at a distance.
If a wall-sized screen disguised at the edges is put in a seminar room and the audience walks in together, it would be a challenge to distinguish a real speaker at the front of the room from a speaker shown on the big screen. Eye tracking software can adjust the screen image as the viewer changes position to give the impression of 3D. Or the audience can wear virtual reality glasses like Oculus Rift.
Other than habit, commitment may be a reason for physical travel. If a person has travelled to give a seminar, the audience would feel embarrassed for not attending. This would be felt less if the presentation is via video and could be recorded. Then the option to watch it later would give people the excuse to constantly postpone watching. If an academic travels to a conference, there are fewer distractions than at home or at work, so a greater chance of actually going to the presentations.
The proliferation of laptops, smartphones and tablets is undermining this commitment – one can attend a talk and not pay attention, checking email or surfing the web instead. Google Glasses would have an even stronger effect: the eyes can be pointed towards the speaker while actually watching and listening something else.