In this paper we introduce a variant of membrane systems with elementary division and without charges. We allow only elementary division where the resulting membranes are identical; we refer to this using the biological term symmetric division. We prove that this model characterises P and introduce logspace uniform families. This result characterises the power of a class of membrane systems that fall under the so-called P conjecture for membrane systems.
['Niall Murphy', 'Damien Woods']
Active membrane systems without charges and using only symmetric elementary division characterise P