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Massively parallel computing on an organic molecular layer


Modern computers operate at enormous speeds—capable of executing in excess of 1013 instructions per second—but their sequential approach to processing, by which logical operations are performed one after another, has remained unchanged since the 1950s. In contrast, although individual neurons of the human brain fire at around just 103 times per second, the simultaneous collective action of millions of neurons enables them to complete certain tasks more efficiently than even the fastest supercomputer. Here we demonstrate an assembly of molecular switches that simultaneously interact to perform a variety of computational tasks including conventional digital logic, calculating Voronoi diagrams, and simulating natural phenomena such as heat diffusion and cancer growth. As well as representing a conceptual shift from serial-processing with static architectures, our parallel, dynamically reconfigurable approach could provide a means to solve otherwise intractable computational problems.

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Figure 1: The concept of a wireless molecular circuit.
Figure 2: Discrete logic-state transport rules.
Figure 3: Information encoding, retrieving, transport and logic-gate operation.
Figure 4: Computing constructs, density classification and Voronoi decomposition.
Figure 5: Mimicking natural phenomenon I: electron diffusion.
Figure 6: Mimicking natural phenomenon II: evolution of cancer cells.

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Authors acknowledge H. Hossainkhani, Y. Wakayama, J. Rampe, M. McClain, W. Cantrel and J. Liebescheutz for discussion. The work is partially funded by the Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan during 2005–2008 and Grants in Aid for Young Scientists (A) for 2009–2011, Grant number 21681015. R.P. acknowledges National Science Foundation (NSF) Award number ECCS-0643420.

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A.B. designed the research; A.B. did the experiment; A.B. developed the CA simulator; R.P., A.B. and S.S. did the theoretical studies; A.B., R.P., S.S. and F.P. analysed the data; and A.B., R.P., F.P. and S.S. wrote the paper together; D.F. reviewed the work.

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Correspondence to Anirban Bandyopadhyay.

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The authors declare no competing financial interests.

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Bandyopadhyay, A., Pati, R., Sahu, S. et al. Massively parallel computing on an organic molecular layer. Nature Phys 6, 369–375 (2010).

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