# Michael Frank

**Biography:** My first exposure to the thermodynamics of computation was in 1985 when I read a Scientific American article (1) about the subject during high school. Then in 1988, I took the world's first class on Nanotechnology, taught by the visionary K. Eric Drexler at Stanford University, in which Drexler discussed an architecture (2-4) for reversible nanomechanical computation which he was designing at MIT. I graduated from Stanford in 1991 with distinction with a B.Sci. in Symbolic Systems (focusing on CS and AI), and went on to do my graduate work in the EECS department at MIT. After completing a Masters thesis on decision-theoretic methods in AI (5), I decided that we really needed faster computers and so, with support from an NSF Graduate Fellowship, I began studying nanoscale computation in earnest. In 1995 I designed the world's first method for universal computation using DNA chemistry (6); this method was required to be reversible for fundamental thermochemical reasons. I then joined the DARPA-funded MIT Reversible Computing Project, led by the legendary hacker (7) Tom Knight, and cellular automata expert (8) Norm Margolus, who was an alumnus of the Information Mechanics group (9) led by Ed Fredkin, former director of the MIT Lab for Computer Science and inventor of the Billiard-Ball Model of computation (10), which was the first ballistic model of reversible computation. Knight and his student Saed Younis had invented the first complete fully adiabatic and reversible CMOS-based logic technology (11), and in the subsequent project, I and other students built on their work to create the first adiabatic and fully-reversible universal processor chips (12,13). During this period I also showed that the aggregate performance of parallel 3D adiabatic reversible machines scales better physically (by polynomial factors), within power dissipation constraints, than any possible irreversible computing architecture (14-15). My 1999 MIT doctoral dissertation (16) derived several other related scaling results, and explored a number of other aspects of reversible computing, from physics through application algorithms. After graduating, I continued my research in faculty positions at the University of Florida (17) and Florida State University (18), and currently as a senior-level engineering scientist at Sandia National Laboratories (19). While at UF and FSU, I occasionally taught a research survey course on The Physical Limits of Computation (20). In 2005 I organized the first workshop on reversible computing (21) and I currently serve on the program committee for the ongoing Reversible Computation conference series (22). Recently, I have reviewed and clarified the foundations of Landauer's principle (23-25) and reversible computing theory (26-28), and I am also presently working on a couple of funded R&D projects at Sandia which are aiming to demonstrate new engineering implementations of reversible computing (29). Numerous of my other papers and talks in this field are available through my research webpages (17-19).

**Field(s) of Research:** Computer Science Engineering to Address Energy Costs, Computer Science Theory, Logically Reversible Computing

## Related links

- (1) C.H. Bennett and R. Landauer, "The Fundamental Physical Limits of Computation," Scientific American, July 1985.
- (2) K. Eric Drexler, Engines of Creation: The Coming Era of Nanotechnology, Anchor Books, 1987.
- (3) K. Eric Drexler, Molecular Machinery and Manufacturing with Applications to Computation, Ph.D. thesis, MIT, 1991.
- (4) K. Eric Drexler, Nanosystems: Molecular Machinery, Manufacturing, and Computation, Wiley, 1992.
- (5) M.P. Frank, Advances in Decision-Theoretic AI: Limited Rationality and Abstract Search, M.S. thesis, MIT EECS Dept., 1994.
- (6) M.P. Frank, "Cyclic Mixture Mutagenesis for DNA-Based Computing," unpublished Ph.D. proposal, MIT EECS Dept., Sep. 1995.
- (7) Steven Levy, Hackers: Heroes of the Computer Revolution, Doubleday, 1984.
- (8) Tommaso Toffoli and Norman Margolus, Cellular Automata Machines: A New Environment for Modeling, MIT Press, 1987.
- (9) Information Mechanics group home page.
- (10) Edward Fredkin and Tommaso Toffoli, "Conservative Logic," IJTP 21(3/4), 1982.
- (11) Saed G. Younis and Thomas F. Knight, Jr., "Practical implementation of charge recovering asymptotically zero power CMOS," Proc.1993 Symp. on Research on Integrated Systems, MIT Press, pp. 234-250.
- (12) M.J. Ammer, M. Frank, T. Knight, N. Love, N. Margolus, and C. Vieri, "A Scalable Reversible Computer in Silicon," Unconventional Models of Computation, Calude, Casti, Dineen (eds.), Springer, 1998.
- (13) C. Vieri, M.J. Ammer, M. Frank, N. Margolus, T. Knight, "A Fully Reversible Asymptotically Zero Energy Microprocessor," in Power Driven Microarchitecture Workshop, pp. 138-142, May 1998.
- (14) M.P. Frank and T.F. Knight, Jr., "Ultimate Theoretical Models of Nanocomputers," Nanotechnology 9(3), 1998.
- (15) M.P. Frank, T.F. Knight, Jr., and N.H. Margolus, "Reversibility in optimally scalable computer architectures," Unconventional Models of Computation, Calude, Casti, Dineen (eds.), Springer, 1998.
- (16) M.P. Frank, Reversibility for Efficient Computing, Ph.D. thesis, MIT EECS Dept., June 1999.
- (17) Archived copy of my old home page at UF
- (18) My old home page at FSU (still up)
- (19) My new home page at Sandia
- (20) Physical Limits of Computing course directory
- (21) RC'05 home page
- (22) Reversible Computation conference series
- (23) M.P. Frank, "Physical Foundations of Landauer's Principle," invited paper, 10th Conf. on Reversible Computation, Leicester, UK, Sep. 2018.
- (24) M.P. Frank, "Physical Foundations of Landauer's Principle," slides for invited talk, 10th Conf. on Reversible Computation, Leicester, UK, Sep. 2018.
- (25) M.P. Frank, "Physical Foundations of Landauer's Principle," extended postprint, arxiv:1901.10327 (cs.ET), Jan. 2019.
- (26) M.P. Frank, "Foundations of Generalized Reversible Computing," 9th Conf. on Reversible Computation, Kolkata, India, July 2017.
- (27) M.P. Frank, "Foundations of Generalized Reversible Computing," talk slides, 9th Conf. on Reversible Computation, Kolkata, India, July 2017.
- (28) M.P. Frank, "Generalized Reversible Computing," extended postprint, arxiv:1806.10183 (cs.ET), Jun. 2018.
- (29) M.P. Frank, "Reversible Computing as a Path towards Unbounded Energy Efficiency: Challenges and Opportunities," slides for invited talk, 3rd IEEE Int'l. Conf. on Rebooting Computing, Washington, DC, Nov. 2018.