We’ll Meet Again
We'll meet
again,
Don't know where, don't know when,
But I know we'll meet again,
Some sunny day.
Math has something
to add about this.
Meeting means that you are in the same place at the same time as another person. That does not mean that the probability of your being in that same place at the same time as another is the same, but that your two probability distributions overlap.
Again depends on whether the event repeats. A normal random distribution is a logistics distribution, also known as the sech squared distribution because its Probability Density Function, PDF, uses the hyperbolic secant function, 1/(4s)*sech2((x-μ)/2s). The mean location where you are is µ. The most probable location you will be is that location. The odds of you being at location x is defined by the formula. S is the range of the probabilities of your being at another location. A standard normal distribution is one where there is a 50% probability of your being at the mean location, in which case s must be equal to 0.5. If you and that other person share a very similar mean location, and you have met once, then there is a high probability that you will meet again, as shown in the graph on the left below. But if your most probable locations, are very different, i.e. you both are ordinarily not in the same place at the same time as shown in the graph on the right below, then the chances of your probability distributions overlapping in the first place was very small. The “again” depends on the period in which these probability distributions repeat.