People: Lijin Aryananda

Overview:

In the late 1940's, von Neumann started the endeavor to investigate the problem of self-replication by machines. Using a 2-dimensional cellular automaton model, von Neumann conducted a formal investigation to discover the specific features of biological automata that make them self-replicating [Von Neumann 1966]. Since then, various studies of artificial self-replicating machines have followed, using models such as the cellular automata and simple mechanical units. In this project, we seek to explore the ambitious question of how to construct self-replicating non-trivial robots. In nature, we observed that evolution first generated self-replicating single-celled organisms. Multicellular organisms didn't appear in abundance until approximately 550 million years ago, during the Cambrian explosion. Based on this observation, we propose to divide our target problem into two parts: how to construct self-replicating simple robots and how these units may aggregate to form self-replicating non-trivial robots?

Goal:

Multi-cellularity is thought to have evolved at least three times independently (i.e. in animals, plants, and fungi) from single-celled organisms. Metazoans, highly complex multi-cellular creatures with specialized organs, abruptly appear fully-formed in the fossil record, without any available intermediates to link them to their unicellular ancestors. This leaves the question of how multi-cellularity emerged from single-celled organisms as one of the great, as yet unsolved mysteries of evolution.In this project, we plan to carry out various computational experiments to study the following issues: how do unicellular aggregates form and under what conditions are they more beneficial? why do individuals in aggregates surrender their ability to reproduce? how does unicellular organism's self-reproducing mechanism evolve to the self-reproducing mechanism in multi-celled organism? how does differentiation emerge in multi-cellular organisms? Our hope is that the answers to these questions can be ultimately applied in designing complex robots that self-replicate.

Reference:

J. von Neumann. Theory of Self-Reproducing Automata. University of Illinois Press, Illinois, 1966.