I have two difficulties with the abstract (not having read the entire paper.)  First is while I don't dispute the claim that the heart cells are capable of turing-machine activities (conveniently forgetting the infinite tape as noted by cjg), it isn't evident that the heart's activities are limited to what the turning machine can compute.<p>The second thing that i am wondering about is that the heart, like any physical oscillator, is a dynamic system, and as such, is chaotic.  This seems to be an important question regarding the modeling.  Chaos theory won't tell you that your heart won't stop, in fact, it won't give you any comfort that it will be immune to slight changes in its environment, say with increased salt content.<p>And the turing-complete claim about the game of life is clearly for grids that have no bounds.  I suspect that there are not an infinite number of states that the heart and all its cells can encompass.  Thus the heart is not a Turing machine.<p>So I am not seeing any added value of this Turing result that isn't already better described by Chaos theory.