I once worked in an office with a timed motion sensor light switch. If it didn’t detect motion in the office for 20 minutes or so it would turn off the lights.
When I was programming “In The Zone” the lights would switch off repeatedly and often over hours of work. Each time I’d flail my arms briefly to get the lights back and return to the task at hand, back into the zone. Eventually I would get the hint, switch my mind off, stretch and go home to wife and kids.
I enjoyed being in the zone… greatly. I lost track of time. I lost awareness of my surrounds. I was detached from everything around me and was immersed in my task. It felt great but strangely I wasn’t really aware of that feeling when in the zone.