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Nanotechnology

Nanotechnology. Ralph C. Merkle Principal Fellow, Zyvex. Health, wealth and atoms. Arranging atoms. Diversity Precision Cost. Richard Feynman,1959. There’s plenty of room at the bottom. Eric Drexler, 1992. President Clinton, 2000.

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Nanotechnology

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  1. Nanotechnology Ralph C. Merkle Principal Fellow, Zyvex

  2. Health, wealth and atoms

  3. Arranging atoms • Diversity • Precision • Cost

  4. Richard Feynman,1959 There’s plenty of room at the bottom

  5. Eric Drexler, 1992

  6. President Clinton, 2000 “Imagine the possibilities: materials with ten times the strength of steel and only a small fraction of the weight -- shrinking all the information housed at the Library of Congress into a device the size of a sugar cube -- detecting cancerous tumors when they are only a few cells in size.” The National Nanotechnology Initiative

  7. Today

  8. Arrangements of atoms . Today

  9. The goal .

  10. Bearing

  11. Planetary gear

  12. Fine motion controller

  13. Robotic arm

  14. σ: mean positional error k: restoring force kb: Boltzmann’s constant T: temperature

  15. σ: 0.02 nm (0.2 Å) k: 10 N/m kb: 1.38 x 10-23 J/K T: 300 K

  16. Making diamond today • Carbon • Hydrogen • Add energy • Grow diamond film.

  17. Hydrogen abstraction tool

  18. Some other molecular tools

  19. Experimental work H. J. Lee and W. Ho, SCIENCE 286, p. 1719, NOVEMBER 1999

  20. Self replication

  21. Complexity of self replicating systems (bits) • Von Neumann's • constructor 500,000 • Mycoplasma genitalia 1,160,140 • Drexler's assembler 100,000,000 • Human 6,400,000,000

  22. Exponential assembly

  23. The impact • Computers • Medicine • Environment • Military • Space

  24. The Vision Powerful Computers • We’ll have more computing power in the volume of a sugar cube than the sum total of all the computer power that exists in the world today • More than 1021 bits in the same volume • Almost a billion Pentiums in parallel

  25. The Vision Nanomedicine • Disease and ill health are caused largely by damage at the molecular and cellular level • Today’s surgical tools are huge and imprecise in comparison http://www.foresight.org/Nanomedicine

  26. The Vision Nanomedicine • In the future, we will have fleets of surgical tools that are molecular both in size and precision. • We will also have computers much smaller than a single cell to guide those tools.

  27. The Vision Nanomedicine • Killing cancer cells, bacteria • Removing circulatory obstructions • Providing oxygen (artificial red blood cells) • Adjusting other metabolites

  28. The Vision Nanomedicine • By Robert Freitas, Zyvex Research Scientist • Surveys medical applications of nanotechnology • Volume I (of three) published in 1999 http://www.foresight.org/Nanomedicine

  29. A Revolution • Today, loss of cell function results in cellular deterioration: function must be preserved • With medical nanodevices, passive structures can be repaired. Cell function can be restored provided cell structure can be inferred: structure must be preserved

  30. Cryonics 37º C 37º C Restore to health Freeze -196º C (77 Kelvins) Temperature Time (some decades)

  31. Clinical trials • Select N subjects • Freeze them • Wait 100 years • See if the medical technology of 2100 can indeed revive them But what do we tell those who don’t expect to live long enough to see the results?

  32. What to do? Join the control group or the experimental group? (www.alcor.org)

  33. Human impact on the environment depends on The Vision • Population • Living standards • Technology

  34. Restoring the environmentwith nanotechnology The Vision • Low cost hydroponics • Low cost solar power • Pollution free manufacturing

  35. The Vision Military applications of molecular manufacturing have even greater potential than nuclear weapons to radically change the balance of power. Admiral David E. Jeremiah, USN (Ret) Former Vice Chairman, Joint Chiefs of Staff November 9, 1995 http://www.zyvex.com/nanotech/nano4/jeremiahPaper.html

  36. The Vision Lighter, stronger, smarter, less expensive • New, inexpensive materials with a strength-to-weight ratio over 50 times that of steel • Critical for aerospace: airplanes, rockets, satellites… • Useful in cars, trucks, ships, ...

  37. Space The Vision • Launch vehicle structural mass could be reduced by a factor of 50 • Cost per kilogram for that structural mass could be under a dollar • Which will reduce the cost to low earth orbit by a factor 1,000 or more • http://science.nas.nasa.gov/Groups/Nanotechnology/ • publications/1997/applications/

  38. Summation Nanotechnology offers ... possibilities for health, wealth, and capabilities beyond most past imaginings. K. Eric Drexler

  39. Quantum uncertainty Born-Oppenheimer approximation • A carbon nucleus is more than 20,000 times as massive as an electron • Assume the atoms (nuclei) are fixed and unmoving, and then compute the electronic wave function • If the positions of the atoms are given by r1, r2, .... rN then the energy of the system is: E(r1, r2, .... rN) • This is fundamental to molecular mechanics

  40. Quantum uncertainty Ground state quantum uncertainty σ2: positional variance k: restoring force m: mass of particle ħ: Planck’s constant divided by 2π

  41. Quantum uncertainty A numerical example • C-C spring constant: k~440 N/m • Typical C-C bond length: 0.154 nm • σ for C in single C-C bond: 0.004 nm • σ for electron (same k): 0.051 nm

  42. Molecular mechanics Basic assumptions • Nuclei are point masses • Electrons are in the ground state • The energy of the system is fully determined by the nuclear positions • Directly approximate the energy from the nuclear positions, and we don’t even have to compute the electronic structure

  43. Molecular mechanics Example: H2 Energy Internuclear distance

  44. Molecular mechanics Parameters • Internuclear distance for bonds • Angle (as in H2O) • Torsion (rotation about a bond, C2H6 • Internuclear distance for van der Waals • Spring constants for all of the above • More terms used in many models • Quite accurate in domain of parameterization

  45. Pump

  46. I I Positional devices Manipulation and bond formation by STM Saw-Wai Hla et al., Physical Review Letters 85, 2777-2780, September 25 2000

  47. A hydrocarbon bearing Molecular machines http://www.zyvex.com/nanotech/bearingProof.html

  48. Self replication The Von Neumann architecture Computer Constructor http://www.zyvex.com/nanotech/vonNeumann.html

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