If you just start walking, eventually you’ll bump into someone.
This might take a while. You might be lucky and walk right into a crowd of people, but if you’re in a sparsely inhabited area, it could take weeks. If you start walking from a random location in an area containing some number of people, you can calculate the time it will take to run into someone by using the physics concept of a mean free path:
time per collision = 1 / collisions per hour = 1 / (shoulder width + average torso diameter) × speed × population density of area
Some areas certainly make encounters easier than others. Here’s the average collision interval for a few different regions:
Canada: 2.5 days
France: 2 hours
Delhi: 75 seconds
Paris: 40 seconds
Mercedes-Benz Stadium in Atlanta during a sold-out game: 0.6 seconds
