time travel

the 1st rule of time travel: it is only possible to compare or combine values at the same point in time

the 2nd rule of time travel: to move a flow forward in time,
you must compound it
FVn=Cx(1+r)^n

the 3rd rule of time travel: to move a flow backward in time,
we must discount it
PV=C/[(1+r)^n]

And now, you can apply these general rules in a different spectrum of time dimension

Present value of a Perpetuity
PV(C in perpetuity) = C/r

Present value of an Annuity
PV(annuity of C for N periods with r)=Cx(1/r)x[1-r/(1+r)^N]

or

PV(annuity)=Cx(1/r)x[(1+r)^N-1]

or

PV(growing perpetuity)=C/(r-g)

or even

PV=Cx1/(r-g)[1-(1+g/(1+r))^N)]

there are so many things in mathematics
that can guide us to realise things in life.
to question, or to remind ourselves
about the things that get easily forgotten
and to let us realise the things
we may not have already noticed and cherished.
it’s like listening to a nostalgic song
and having a deja vu,
followed by hitherto unseen vistas in your mind.

excessively short is our lifetime

i wish i was a puppeteer, a trapeze artist, an astronaut, a chef, a travelling photographer for the National Geographic Magazine, a NY curator and a sweet grandmother, and i wonder where in the world i’d be right now.