In a nutshell, it is a theoretical model inspired by biology, but which produces many interesting results, as super-Turing computational power.
I am not sure whether it is still, but the reference on web for the subject was http://ppage.psystems.eu/ .
Besides Păun, other big names in the topic are Perez-Jimenez, Gheorghe and Manca.
As far as I am concerned, there are little practical application of it, even though the theoretical potential is considerable.
I tried to focus on more day-to-day application of MP [2], and I managed to get some nice results, but further advance was limited by external forces.
Do I recommend to buy an introductory book on the subject? No, mostly because I think the material online from the people I mentioned above, plus their publication, is more than enough to acquire the knowledge. Besides, I bet the book is published by Elsevier, which usually mean it is a simple collection of papers, except the fact I am not fan of that publishing house.
If you have any more direct question, feel free to contact me—hopefully I can be of some help.
But, I have the impression that membrane computing is still a very academic topic disconnected from the engineering world.
If it is what you like, then it might satisfy you. :)
[1]: https://ricardo.guiraldelli.com/research.html#doctorate
[2]: https://ricardo.guiraldelli.com/research.html#available-mate...
https://en.wikipedia.org/wiki/P_system
https://en.wikipedia.org/wiki/Cell_membrane
Huh. Wasn't familiar with this before now. Looks very interesting though.
https://www.cs.auckland.ac.nz/research/groups/CDMTCS/researc...
This seems like a huge problem for any electronic representation, since most any computational approach will deliver "super-Turing" results if you allow the machine to grow faster than the problem...
I was reading George Gilder back in the 1980s when that idea hit me, and its been in the back of my brain ever since.
I wouldn't bother without a specific need that can be accelerated with biochemistry directly. Turing completeness can't be improved on.