Nanotechnology Ralph C Merkle Principal Fellow Zyvex 2

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 The National Nanotechnology Initiative “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. ” 7

Today 8

Arrangements of atoms. Today 9

The goal. 10

Bearing 11

Planetary gear 12

Fine motion controller 13

Robotic arm 14

σ: k: kb: T: mean positional error restoring force Boltzmann’s constant temperature 15

σ: k: kb: T: 0. 02 nm (0. 2 Å) 10 N/m 1. 38 x 10 -23 J/K 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 • Mycoplasma genitalia • Drexler's assembler • Human 500, 000 1, 160, 140 100, 000 6, 400, 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 26

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 27

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. 28

The Vision Nanomedicine • • Killing cancer cells, bacteria Removing circulatory obstructions Providing oxygen (artificial red blood cells) Adjusting other metabolites 29

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 30

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 31

Cryonics Temperature 37º C Restore to health Freeze -196º C (77 Kelvins) Time (some decades) 32

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? 33

What to do? Join the control group or the experimental group? (www. alcor. org) 34

The Vision Human impact on the environment depends on • Population • Living standards • Technology 35

The Vision Restoring the environment with nanotechnology • Low cost hydroponics • Low cost solar power • Pollution free manufacturing 36

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/nano 4/jeremiah. Paper. html 37

The Vision Lighter, stronger, smarter, less expensive • New, inexpensive materials with a strengthto-weight ratio over 50 times that of steel • Critical for aerospace: airplanes, rockets, satellites… • Useful in cars, trucks, ships, . . . 38

The Vision Space • 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. nasa. gov/Groups/Nanotechnology/ publications/1997/applications/ 39

Summation Nanotechnology offers. . . possibilities for health, wealth, and capabilities beyond most past imaginings. K. Eric Drexler 40

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 r 1, r 2, . . r. N then the energy of the system is: E(r 1, r 2, . . r. N) • This is fundamental to molecular mechanics 41

Quantum uncertainty Ground state quantum uncertainty σ 2: k: m: ħ: positional variance restoring force mass of particle Planck’s constant divided by 2π 42

Quantum uncertainty A numerical example • • C-C spring constant: Typical C-C bond length: σ for C in single C-C bond: σ for electron (same k): k~440 N/m 0. 154 nm 0. 004 nm 0. 051 nm 43

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 44

Molecular mechanics Energy Example: H 2 Internuclear distance 45

Molecular mechanics Parameters • • Internuclear distance for bonds Angle (as in H 2 O) Torsion (rotation about a bond, C 2 H 6 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 46

Pump 47

Positional devices I I Manipulation and bond formation by STM Saw-Wai Hla et al. , Physical Review Letters 85, 2777 -2780, September 25 2000 48

Molecular machines A hydrocarbon bearing http: //www. zyvex. com/nanotech/bearing. Proof. html 49

Self replication The Von Neumann architecture Computer Constructor http: //www. zyvex. com/nanotech/von. Neumann. html 50

Self replication Drexler’s architecure for an assembler Molecular computer Molecular constructor Positional device Tip chemistry 51

Self replication A C program that prints out an exact copy of itself main(){char q=34, n=10, *a="main() {char q=34, n=10, *a=%c%s%c; printf(a, q, n ); }%c"; printf(a, q, n); } 52

Self replication English translation: Print the following statement twice, the second time in quotes: “Print the following statement twice, the second time in quotes: ” 53

Self replication An overview of self replicating systems for manufacturing • Advanced Automation for Space Missions, edited by Robert Freitas and William Gilbreath NASA Conference Publication 2255, 1982 • A web page with an overview of replication: http: //www. zyvex. com/nanotech/self. Rep. html 54