Multi-Valued and Parallel Molecular Logic
E Collini, RD Levine, F Remacle, S Rogge and I Willner
Current computing machines are designed on the basis of a Boolean algebraic model where a variable, an input or an output, is two-valued. The logic is performed by combinational gates that provide an output that depends only on the input. MULTI makes a radical departure from this prevailing Boolean paradigm and proposes a new approach to logic and computing taking advantage of the atomic and molecular scales.
MULTI follows a physically motivated approach to computing at the nanoscale that gives up the notion of a Boolean gate implemented as a network of switches as well as the design of such gates connected sequentially to one another. In order to lay the foundations of physically motivated novel ways to compute at the molecular scale, the basic questions that MULTI aims to answer is ‘what is a natural and efficient way for a molecular or a supra(bio)molecular logic device to physically operate’ and ‘how do we input different instructions to such a device’ and ‘how does the inherent time evolution of the device deliver different outputs for different inputs’, ‘what are the physics features required for programming a device at the molecular scales’. Taking into account the inherent physical properties of the atomic and molecular scale devices, MULTI can naturally address the questions of ‘can we simultaneously deliver more than one output for a given input’ and ‘can the device remember what it previously went through so that the next outputs depend not only on the present inputs but also on the current state of the device’ and ‘can one use physical variables represented as real numbers for computing’. MULTI proposes that this physically motivated approach to ‘what is computing’ is a way to make breakthroughs and deliver novel capabilities for implementing logic at the nanoscale that goes beyond the von Neumann and Turing models.
Keywords: Molecular logic, dopant structures, DNAzymes, 2D photo echo spectroscopy, molecular automaton, parallel computing, multivalued logic