2 Nanotechnology Ralph C. Merkle Principal Fellow, Zyvex

3 Health, wealth and atoms

4 Arranging atoms Diversity Precision Cost

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

6 Eric Drexler, 1992

7 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

8 Today

9 Arrangements of atoms. Today

10 The goal.

11 Bearing

12 Planetary gear

13 Fine motion controller

14 Robotic arm

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

16 σ:0.02 nm (0.2 Å) k: 10 N/m k b : 1.38 x J/K T:300 K

17 Making diamond today Carbon Hydrogen Add energy Grow diamond film.

18 Hydrogen abstraction tool

19 Some other molecular tools

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

21 Self replication

22 The Von Neumann architecture ComputerConstructor

23 Molecular computer Molecular constructor Positional deviceTip chemistry Drexler’s architecure for an assembler

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

25 Print the following statement twice, the second time in quotes: “Print the following statement twice, the second time in quotes:” English translation:

26 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:

27 Von Neumann's constructor 500,000 Mycoplasma genitalia 1,160,140 Drexler's assembler 100,000,000 Human6,400,000,000 Complexity of self replicating systems (bits)

28 Exponential assembly

29 The impact

30 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 bits in the same volume Almost a billion Pentiums in parallel Powerful Computers

31 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 Nanomedicine

32 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. Nanomedicine

33 Human impact on the environment depends on Population Living standards Technology

34 Restoring the environment with nanotechnology Low cost hydroponics Low cost solar power Pollution free manufacturing

35 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,... Lighter, stronger, smarter, less expensive

36 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

37 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 publications/1997/applications/

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

40 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 Quantum uncertainty

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

42 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 Quantum uncertainty A numerical example

43 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 Molecular mechanics

44 Example: H 2 Internuclear distance Energy Molecular mechanics

45 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 Molecular mechanics

46 Pump

47 Saw-Wai Hla et al., Physical Review Letters 85, , September Manipulation and bond formation by STM II Positional devices

48 A hydrocarbon bearing

49 Killing cancer cells, bacteria Removing circulatory obstructions Providing oxygen (artificial red blood cells) Adjusting other metabolites Nanomedicine

50 By Robert Freitas, Zyvex Research Scientist Surveys medical applications of nanotechnology Volume I (of three) published in 1999 Nanomedicine

51 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

52 37 º C -196 º C (77 Kelvins) Freeze Restore to health Time Temperature (some decades) Cryonics

53 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? Clinical trials

54 Join the control group or the experimental group? ( What to do?