Abstract
We experience two kinds of time, namely, physical time t and psychological timeτ, simultaneously. In this paper, loci of the variables (t,τ) through a life time were analyzed ,especially at the beginning and the final stages. The relativistic effect on times was ignored because of the low speed.
A nondimensional parameterαwas proposed, which represents the vital body functions. α is a function of physical time t. It was supposed thatαtakes the value of zero at the beginning time and the ending time of life, while in intermediate normal time it takes a value of nonzero positive value of order 1. The functionαwas supposed to be continuous and differentiable.
On the other hand, a human being has a mind, which creates psychological timeτ.
Each of three variables t,τand α does not change independently. The differential equation (1) which combines the three variables was proposed as follows (Equation of Two Times or shortly Life Index Equation).
dt/dτ=α(t) (1).
The function form of α(t) was proposed by applying Taylor's theorem without losing generality. Under the above conditions , (t-τ）locus was calculated. The results are as follows.
Suppose a lifetime of a person, [t_1,t_2],on t-τplane. The locus is described in the form of
τ(t)=f(t),in which t_1≤t≤t_2 .
(1) f(t) is a monotone increasing function.
(2)While physical time t moves in a finite interval (t_1,t_2) , psychological timeτchanges in an infinite region (-∞,+∞).
In other words, lifetime is finite objectively, nevertheless it is infinite subjectively.
