What are the consequences of achieving physical immortality?

[Marc]

I remember reading about cases where a woman in a long coma appears to have not aged a bit, but as soon as she woke up she become a old woman in a matter of days.

Fascinating. I need to find the primary source for this. Do you happen to know it?

The age is actually set in time/space and when you try to 'trick time' it doesn't work out. The 'spirit age' tells the physical age what it should be. For more info check out this article: Reciprocal System on Death and immortality

Life units, a stable combination of material and cosmic atoms, differ from inanimate structures in that they have "length" in clock time--the combination only remains viable for a limited duration. The simplest life unit is the compound neutron, a stable motion between a material proton and a cosmic neutrino. Nehru's research indicates that, based on probability mechanics, that motion remains stable for about 13 minutes before the rotational vectors align in such a way that allows the two particles to break the bond and go their separate ways, ending the combination (death).