At the airport

San Francisco departures, hometime. Just over a week ago I wasn't that keen on coming here. Now, I'm pretty keen to stay. This seems fairly common, a form of relocation inertia, or just normal inertia I guess. There must be an equation to describe this. The body resists travel, or a change of location 'flux'. Perhaps Lenz's law fits? Plenty of time to think about it before getting to Heathrow.