y = a(1 - r) to the power of x [part two]

He told me I was living half-lives and a time would come when there would be nothing left to halve. He then taught me the simple function that would define my life.

y = a(1-r)^x

[Where a is the initial amount before decay began (my whole self), r is the rate of my decay (1/2), and x is the number of intervals (my half-lives).] 
My decline continues rapidly, but the rate of change will decrease over time, as there is less and less to halve. A ghost of me may outlive you all. But that ghost's mass will be so insignificant it will not be able to interact with the physical world. In fact, it is likely that it will fall through the earth to further reduce within its core.
[To be continued tomorrow.]